Submarine Relief from Mayotte Survey 2019: Fani Maore Volcano
Credit: Campagne MAYOBS2
Recent discoveries reveal that undersea volcanoes off Madagascar’s coast are releasing chemical signatures from Earth’s primordial magma ocean. This magma ocean formed during the planet’s first 100 million years, offering insights into early Earth’s history.
Geologists posit that the Earth’s mantle—a vast layer of heated rock beneath the crust—has been slowly churning for over four billion years, gradually erasing chemical traces from Earth’s early formation.
“This discovery will significantly change our understanding in earth science,” states Catherine Chauvel from the French National Center for Scientific Research (CNRS) in Paris. “We now have proof that material dating back 4.5 billion years still exists in sufficient quantities to be studied in volcanic systems.”
During the Hadean era, a Mars-sized object collided with Earth, generating intense heat and forming a global magma ocean. As the molten rock solidified over millions of years, the oldest crust began to emerge.
While some scientists believed remnants of this primordial crystallization remained in the mantle, they lacked the analytical methods to confirm it, according to Chauvel.
An unusual swarm of earthquakes in May 2018 off Mayotte Island, located between Madagascar and Mozambique, led to the discovery of a new volcano, Fani Maore, approximately 50 kilometers eastward. Over the subsequent three years, eruptions released significant magma, causing the island to sink around 20 centimeters.
Chauvel and her research team collected volcanic rock samples from both Fani Maore and nearby Mayotte Island to analyze the chemical composition of the new volcano versus older volcanic systems. Collaborating with Claudine Israel, they are employing cutting-edge ultra-high precision techniques at the University of Cambridge to assess variations in neodymium isotopes, which preserve a chemical record of the crystallization process from Earth’s primordial magma ocean.
Initial findings indicate that Fani Maore’s lava has a higher proportion of neodymium-142 and neodymium-144 compared to that from Mayotte, suggesting pockets in the ancient mantle have remained undisturbed by billions of years of geological mixing. These pockets are relatively rich in bridgmanite, a mineral believed to have first crystallized from Earth’s primordial magma ocean.
“Finding something that has eluded others is always thrilling,” remarks Chauvel.
This discovery implies that Earth’s mantle may not have mixed as extensively as previously thought, thus aiding scientists in reconstructing how Earth’s primordial magma ocean solidified, according to Israel.
“We experimentally demonstrate how the mantle crystallizes from a magma ocean, creating chemical diversity from the very beginning,” she notes.
Tim Johnson at Curtin University in Perth, Australia, claims that this finding serves as compelling evidence that Earth’s mantle still houses ancient material. “This is a significant breakthrough,” he asserts.
“Despite the challenges in perfecting such technology, the results are impressive,” adds Bernard Bourdon from CNRS in Lyon.
This research provides unprecedented insights into an era of Earth’s history with limited direct evidence, akin to uncovering a core sample that made its way to the surface, Bourdon concludes.
According to Richard Carlson from Carnegie Science in Washington, D.C., the accuracy of this study is remarkable. “Those familiar with these measurements will recognize this achievement as substantial,” he remarks.
Internet Explorer 11 is no longer supported. For an optimal experience, we recommend accessing our site via a modern browser.
Currently playing
AI-Powered Robots for Ocean Exploration
02:52
Robotic Dogs and Drones: A New Era for Police
02:00
Top Stories
Discover the groundbreaking Greensea IQ robot, an AI-powered marvel designed to detect and neutralize underwater mines, enhancing safety in ocean explorations. Reported by NBC News’ Brian Chang. July 2, 2026
Currently playing
AI-Powered Robots for Ocean Exploration
02:52
Top Stories
Top Stories
Key SEO Optimizations:
Descriptive Alt Attributes: Used meaningful alt texts for images to enhance visibility in image search.
Relevant Titles: Ensured video titles capture attention and include keywords (like “AI-Powered Robots” and “Massachusetts State Police”), aiding search relevance.
Structured Data: Maintained logical HTML structure for better indexing by search engines.
Feel free to adjust any specific sections or details according to your needs!
Satellite images reveal a significant phytoplankton bloom in the Arctic Ocean near Svalbard, contributing to a noticeable green hue.
Credit: European Union, Copernicus Sentinel 2 images
Melting sea ice in the Arctic is increasingly allowing sunlight to penetrate, which supports the growth of phytoplankton and other marine life. However, this phenomenon is causing nutrient depletion in certain areas, potentially disrupting the ecosystems that support seals, polar bears, and commercial fish populations in the North Atlantic.
Phytoplankton, essential photosynthetic organisms, serve as the foundation of the marine food web. Recent studies indicate unprecedented increases in phytoplankton blooms, as evidenced by satellite measurements of chlorophyll levels. However, since 2009, overall growth has notably slowed in many regions, particularly on the Atlantic side of the Arctic. Research from Raja Ganeshram and his team at the University of Edinburgh highlights how high phytoplankton levels in the Pacific are depleting nearby nitrate levels, critical for their development.
According to Ganeshram, “Arctic warming impacts ecosystems beyond just sea ice and temperature reductions. This affects food resources both in the Arctic and the North Atlantic, impacting the entire region in ways we are still deciphering.”
Nitrogen is a key nutrient for all forms of plant life, including terrestrial flora and phytoplankton. Recent findings show that nutrient-rich waters from the Pacific, flowing through the Bering Strait into the Chukchi Sea, are vital for sustaining phytoplankton productivity in the Arctic. These nutrients are carried by ocean currents to the Atlantic Ocean, particularly through the Fram Strait between Greenland and Svalbard.
The team led by Ganeshram analyzed nutrient data from the Fram Strait, gathered during icebreaker missions from 1998 to 2023. Their findings reveal a significant decline in nitrate levels since 2009, coinciding with a shift toward reduced sea ice extents. Most nitrate influx from the Pacific is absorbed in the Chukchi Sea, where melting ice exposes waters to more sunlight.
This increased phytoplankton growth leads to higher rates of decomposition, as aerobic bacteria break down the organic material, consuming oxygen. Once the available oxygen is exhausted, anaerobic microorganisms take over, decomposing phytoplankton and depleting nitrates. By the time these waters reach the Fram Strait, a vital nutrient has been lost.
This depletion means that diatoms, a type of algae that thrives in nitrate-rich environments, are no longer prevalent in the Fram Strait. Currently, microplankton dominate, as they can efficiently utilize nitrogen from ammonium sources. This shift may disrupt food chains, as smaller zooplankton must consume these smaller phytoplankton before they can transfer energy to larger organisms, further compounding the challenges for fisheries and human communities reliant on marine resources.
The changing dynamics of nutrient flow into the North Atlantic is expected to alter phytoplankton composition, with significant implications for commercial fisheries. These results suggest that phytoplankton growth is increasingly limited by nutrient availability rather than by sunlight, signaling a potential halt in growth across the Arctic Ocean. According to Jean-Eric Tremblay, a researcher at Laval University in Quebec City, not involved in the study, “This shows the Arctic Ocean may not become the future oasis we hope for. Increased phytoplankton production could enhance denitrification, further depleting nitrates and reducing productivity.”
The researchers conclude that the Arctic ecosystem has likely crossed a tipping point. “While year-to-year variations may occur, the recovery of sea ice to previous states is improbable,” says Marta Santos Garcia, also from the University of Edinburgh. “The ongoing loss of nitrate is unlikely to be reversible.”
During the winter of 2013-2014, shifts in the jet stream led to the emergence of a significant warm water mass dubbed the “blob,” which extended over 1,500 kilometers across the North Pacific Ocean. This phenomenon was detected by floating instruments anchored to the ocean floor off the coastlines of Alaska, Washington, and Oregon, alerting scientists and the fishing industry to water temperatures exceeding normal levels by up to 4 degrees Celsius.
These instruments are part of the Ocean Observing Initiative (OOI), which comprised five moorings along the West coast of the United States, as well as off the East coast and in Greenland. The National Science Foundation (NSF) announced a substantial $220 million investment in 2023, emphasizing the necessity of the OOI for monitoring “Earth’s vital organs.” However, recent announcements from the NSF indicated plans to dismantle most of these arrays due to funding reductions initiated by the previous administration.
Between 2015 and 2016, sensors attached to the OOI mooring wire identified the warm water mass, with temperatures rising significantly influenced by global-warming events, particularly El Niño. This data revealed that occurrences of the blob happened again in 2019 and may be becoming more frequent due to climate change, which has been associated with toxic algae blooms affecting fisheries, such as the $60 million loss from California’s Dungeness crab fishery.
The removal of OOI moorings jeopardizes not only weather forecasts, including precipitation predictions which affect drought conditions in the western U.S., but also the ability to monitor key elements like the Atlantic Meridional Circulation (AMOC), crucial for maintaining Europe’s temperate climate and assessing El Niño impacts.
“We’re flying blind, which ultimately results in greater costs,” states John Abraham from the University of St. Thomas in Minnesota. Operating the OOI costs approximately $56 million annually, while U.S. commercial fisheries, relying heavily on OOI data, generate billions of dollars annually. Weather-related disasters have historically caused damages reaching $183 billion, further emphasizing the importance of accurate data.
Without access to the OOI data, fishing fleets will struggle to determine which areas will be less affected by El Niño events. This upcoming El Niño is predicted by some models to be among the strongest on record. Oyster, clam, and shellfish farms would find it challenging to prepare for diminished temperatures and nutrients caused by El Niño, while scientists would lose sight of significant impacts on marine ecosystems, including the formation of low-oxygen “dead zones.”
“The timing couldn’t be worse,” lamented Hilary Palewski from Boston University, stressing the critical function of OOI in marine research.
Satellites cannot penetrate the ocean’s surface, making data from submerged floats, gliders, and tethered vessels vital for understanding the Earth’s ocean-covered regions, which account for about 70%. These instruments primarily measure temperature, salinity, and flow, but the OOI moorings also assess pH, oxygen, and CO2 levels—essential for comprehending oceanic biology and chemistry, particularly in remote, monitored regions where water mass movements influence climate.
The loss of these sensor networks will also pose challenges globally, especially concerning AMOC observability. The OOI array located in the Irminger Sea, east of Greenland, is part of the OSNAP initiative—a network of gliders and moorings stretching from Canada to Scotland, monitoring the warm saltwater flow, pivotal for the AMOC. A breakdown in this system could result in Europe experiencing severe winter conditions and disrupt essential monsoon rains vital for agriculture in Africa and Asia.
“OSNAP has revealed that most actual capsize events occur east of Greenland, making the Irminger Sea crucial for understanding variability,” notes Femke de Jong from the Royal Netherlands Marine Institute.
Palewski added that dismantling OOI will leave a significant data gap that could hinder future understanding of the AMOC, even if replacement is pursued later.
Scientists are concerned that the dismantling of OOI may herald a drastic reduction in U.S. ocean research funding, risking initiatives like OSNAP and potentially jeopardizing the Argo project, which comprises around 4,000 drifting instrument floats, over half of which are managed by the U.S.
In a statement to New Scientist, the NSF mentioned that the OOI’s removal is aimed at “prioritizing support for evolving scientific priorities.” However, this is contingent on political agendas, with experts like Gretchen Goldman of the Union of Concerned Scientists condemning it as an “attack on science,” amid proposals to cut thousands of research grants and reduce the NSF budget significantly.
This week, new regulations proposed by the administration seek to eliminate peer reviews for research funding applications and empower political appointees rather than independent experts to determine the fate of federally funded studies. Additionally, bans on international cooperation and studies on gender and diversity are planned.
Edward Deaver, a professor at Oregon State University managing the OOI array, emphasizes that both the dismantling of OOI and the proposed grant rule changes constitute sweeping reforms that threaten to undermine peer review and politicize NSF-funded research.
A recent study indicated that dismantling even a fraction of the Global Ocean Observing System, which includes the OOI and Argo floats, could inflate errors in annual ocean heating rates by 33%. This is akin to predicting an unemployment rate of 3% with an imprecise range of 2% to 4%, according to Abraham, a member of the research team.
“This is a calculated move to silence our monitoring of the ocean,” he asserts regarding the OOI dismantling. “If we don’t measure, how can we identify problems?”
Greenhouse gases play a crucial role in trapping heat in the atmosphere, and one significant gas found beneath the ocean floor is methane. This gas is often locked in an icy form known as methane hydrate. When methane hydrate begins to decompose or melt, methane gas is released into the ocean, potentially exacerbating global warming. Factors like thawing permafrost, tectonic activity, tidal shifts, and sea level changes can also trigger methane release from sediments. Despite ongoing research, scientists are still unraveling how these triggers will react to future climate changes.
Researchers have proposed that future global warming might accelerate the influx of methane into the oceans. To explore this hypothesis, they examined an ancient global warming episode that occurred approximately 56 million years ago, known as the Paleocene-Eocene Thermal Maximum (PETM). During this period, temperatures in the Arctic Ocean occasionally soared above 20°C (68°F), serving as a valuable comparison to the current warming conditions we face today.
Once methane is released into seawater, its outcome largely depends on two biological processes. Currently, around 90% of the methane emitted from the ocean floor is consumed by tiny organisms called microorganisms through a process known as anaerobic methane oxidation. During this process, microorganisms use methane along with sulfate, resulting in the production of solid iron-sulfur minerals called pyrite. Anaerobic methane oxidation effectively traps methane in minerals, preventing it from escaping into the atmosphere, thereby transforming the ocean into a reservoir, or sink, for methane.
However, excessive methane can overwhelm the sulfate-dependent cycle. In such cases, another group of microorganisms consumes methane along with oxygen through a process called aerobic methane oxidation. This process removes carbon dioxide, a potent greenhouse gas, from the ocean. While today, about 10% of oceanic methane consumption occurs via aerobic oxidation, this ratio may have differed in geological history.
To investigate the balance of anaerobic versus aerobic methane oxidation during the PETM, researchers analyzed sediments retrieved from the Arctic ocean floor. As sediments accumulate on the ocean floor, they compact over time. Scientists can drill deep and extract cylindrical samples, known as cores, from this compacted sediment.
Within a sediment core, the age of the material increases with depth, meaning that younger sediments are found at the top and older sediments at the bottom. For this project, the team worked with cores sourced from the Arctic Ocean, containing sediments up to 100 million years old. They found evidence of PETM deposits at a depth of 386 meters (1,266 feet) within these cores.
Researchers noted that microbes leave behind distinctive carbon-based molecules called organic biomarkers during decomposition. These organic biomarkers accumulate in sediment layers on the seafloor. Different types of methane-consuming microorganisms produce distinct biomarkers, one for anaerobic and another for aerobic methane oxidation. By measuring the abundance of these biomarkers in sediment cores, the team was able to determine which microorganisms prevailed during the PETM.
The biomarker indicative of aerobic methane oxidation is Hop(17)21-ene. The researchers observed a four-fold increase in Hop(17)21-ene during the PETM. Conversely, the biomarkers associated with anaerobic methane oxidation, Glycerol dialkyl tetraether, decreased by half. These trends suggested a rise in aerobic methane oxidation and a decline in anaerobic processes, attributed to the release of significant amounts of methane during warming conditions, which overwhelmed the sulfate-dependent methane cycle.
To estimate carbon dioxide output from aerobic methane oxidation during the PETM, researchers identified another biomarker in the sediment core, Fitan. This compound, produced by organisms that consume carbon dioxide during photosynthesis, offers clues about historical carbon dioxide levels. The study revealed that during the PETM and long thereafter, carbon dioxide concentrations in the Arctic Ocean were four times greater than today’s levels. This indicates that the Arctic Ocean remained a long-term source of carbon dioxide to the atmosphere, even after the PETM period.
The research team proposed that the increased aerobic methane oxidation observed during the PETM could parallel current trends in the warming Arctic Ocean amid climate change. Their findings underscore the potential dangers of converting methane to carbon dioxide, which further warms the atmosphere, heats the oceans, and triggers additional methane release from the ocean floor—all contributing to a feedback loop that can escalate and hinder recovery efforts.
A continent-like shelf beneath Mars’ surface indicates that a vast ocean may have once covered up to one-third of the planet, reigniting a long-standing debate about Mars’ watery past.
Artist’s impression of Mars as it appeared around 4 billion years ago. Credit: M. Kornmesser / ESO.
While it is widely accepted that Mars had some liquid water on its surface, the existence of long-lasting oceans remains uncertain. It’s debated whether water existed solely in lakes and streams or whether significant oceans formed during Mars’ history.
Previous Mars missions have identified geological features resembling coastlines, but their subtlety and varying elevations complicate their interpretation.
Real coastlines would exhibit consistent elevation across the globe, similar to Earth’s sea level. However, observations suggest otherwise.
“If Mars had an ocean, it likely dried up billions of years ago, more than half of Mars’ age,” states Michael Lamb, a professor at the California Institute of Technology.
“Earth has very few features that are billions of years old, especially after continuous erosion and disturbances over time,” he adds.
“We sought terrain that could provide stronger evidence of such an ancient ocean.”
Illustration from orbiter data showing the coastal shelf region of Mars, a hallmark of global oceans formed over extended periods. Image credit: A. Zaki.
Professor Lamb and Dr. Abdallah Zaki from the California Institute of Technology and the University of Texas at Austin analyzed Earth’s geological features to find indicators of past oceans.
Using computer simulations, they drained ocean models to assess the remaining terrain.
The simulations revealed that a distinct flat landmass, known as the continental shelf, surrounds the region where land meets sea, akin to a ring left by a drained bathtub.
While sea levels have fluctuated on Earth, continental shelves have remained stable, which supports the hypothesis of an ancient Martian ocean.
The researchers utilized topography data from Mars orbiters, discovering similar shelf formations in the northern hemisphere, hinting at an ocean covering a significant portion of the planet.
Such landforms take considerable time to form and are rare in lake environments, supporting the theory of a stable ocean existing for millions of years.
Additionally, evidence of river deltas and coastal features known as “bathtubbling” shelves were observed.
“The discovery of the shelf is a vital observation that consolidates the evidence for a Martian coastal zone,” Dr. Zaki commented.
“This previously overlooked aspect strengthens the case for a northern ocean on Mars, leading to further studies on deposits and satellite data.”
For further details, refer to the publication in Nature.
_____
Zaki, A. & Ram, M.P. Identifying topographical features of the early Martian ocean. Nature, published online April 15, 2026. doi: 10.1038/s41586-026-10381-2
Human-induced global warming is disrupting the Atlantic Meridional Overturning Circulation (AMOC), a critical ocean current system that includes the Gulf Stream, responsible for warming Europe. A total shutdown of the AMOC could trigger a massive release of carbon from deep Antarctic waters into the atmosphere, exacerbating global warming.
Research indicates that an AMOC collapse can lead to severe climatic consequences, including colder winters in Europe and disrupted monsoons in Africa and Asia, while also increasing global temperatures. Recent computer models predict that this scenario could release 640 billion tonnes of carbon dioxide near the South Pole, raising global temperatures by an additional 0.2°C.
“The collapse of the AMOC may trigger large-scale mixing in the Southern Ocean, releasing carbon stored in deep waters,” states Danian, a researcher at the Potsdam Institute for Climate Impact Research. “This outcome is unprecedented.”
The co-authors emphasize that potential catastrophic events can have even more severe implications than previously understood. As Johan Rockström, also from the Potsdam Institute, notes, “We must remain vigilant, as one failure can trigger a domino effect.”
The AMOC operates by transporting warm, salty water from the Gulf of Mexico to the North Atlantic, where it cools, sinks, and circulates back southward along the ocean floor. Scientists believe that increased fresh meltwater from the Greenland ice sheet is diluting the AMOC, thereby slowing its sinking process.
Recent buoy measurements reveal a weakening return flow, suggesting a 15% decline in the AMOC, with models predicting a potential collapse within decades to centuries.
A new study exploring AMOC collapse under varying climate scenarios shows that if atmospheric CO2 levels exceed 350 ppm, the AMOC fails to recover after shutdown. Given the current CO2 level of 430 ppm, this indicates that AMOC decay may be irreversible.
The study also identified that if the AMOC, a key component of the global ocean current conveyor belt connecting the Southern Ocean and Pacific Ocean, collapses, it could lead to deep water convection near the South Pole. This deep water rests under a layer of fresher surface water, where carbon accumulates from both atmospheric CO2 and decaying plankton. The model suggests a significant portion of this carbon would be released into the atmosphere.
Previous research indicates that past AMOC collapses similarly triggered convection near the South Pole, aligning with evidence that the Southern Ocean is becoming less salty. This reduction in salinity disrupts the layered structure above the saltier deep water, facilitating surface access for deep water.
“It’s striking to observe these changes in such a warm climate amid rising CO2 levels,” says Jonathan Baker from the Met Office. “This study is intriguing, yet its findings depend on whether convection in the Southern Ocean intensifies; different models exhibit varied responses, leading to ongoing uncertainties.”
The study also forecasts that AMOC collapse could cool the Arctic by 7 degrees Celsius, freezing regions in Canada, Scandinavia, and Russia while concurrently warming Antarctica by 6 degrees Celsius. The West Antarctic Ice Sheet remains at risk of surpassing its tipping point, which could trigger a larger collapse of the East Antarctic Ice Sheet, resulting in significant sea level rises.
The repercussions of CO2 emissions could persist for over a millennium following any AMOC closure. However, Rockström cautions that continued greenhouse gas emissions may lock in a future collapse of the AMOC in just a few decades.
“The window for change could be as short as the next 25 to 50 years,” he warns. “It’s vital to recognize the urgency; it’s not just about the timing of impacts, but about our commitment to preventing an increasingly inhospitable planet for future generations.”
Visualization of the Western Boundary Current in the Atlantic Meridional Overturning Circulation
Credit: NASA’s Scientific Visualization Studio
The latest buoy measurements indicate that the Atlantic Meridional Overturning Circulation (AMOC), crucial for regulating Europe’s climate, is weakening across four distinct latitudes. This represents the strongest evidence yet that this pivotal ocean current system is slowing and may be nearing collapse.
The AMOC is part of a global oceanic conveyor belt that transports warm, salty water from the Gulf of Mexico to the North Atlantic, helping maintain milder temperatures in Western Europe compared to those in Canada or Russia. As this water cools and sinks, it continues south along the ocean floor on the western side of the Atlantic.
Analysis of historical ocean temperature data suggests a 15% decline in the AMOC since 1950, with computer models predicting a potential closure within decades. However, direct measurements have only been reliable for roughly 20 years, making definitive conclusions difficult.
Recent research in the Western Atlantic has provided compelling evidence of an AMOC slowdown.
“Our findings indicate that Atlantic circulation is indeed weakening at the western boundary, and data from multiple latitudes supports this consistent signal across the broader North Atlantic,” said Qianjiang Xing from the University of Miami, Florida, who led the study.
In 2004, a collaborative effort led by the University of Miami established a series of moorings named RAPID-MOCHA from the Bahamas to the Canary Islands. These measurements, encompassing temperature, salinity, and velocity, allow scientists to estimate pressure changes across the Atlantic, providing insight into how much water is being effectively stored, according to team member Shane Elipot, also from the University of Miami.
Water moves from areas of high pressure to those of low pressure, but the Earth’s counterclockwise rotation causes deflection to the right, leading to reverse circulation. Thus, pressure changes can be indicative of AMOC strength variations.
The latest analysis of RAPID-MOCHA data reveals that AMOC flow is decreasing at a rate of approximately 90,000 cubic meters per second each year—a faster decline than previously observed. This indicates that the AMOC weakened by about 10% from 2004 to 2023.
However, the variation in certainty surrounding this reported change is quite significant. To address this, the study also examined pressure dynamics from three mooring arrays installed along the western Atlantic coast—near the West Indies, the U.S. East Coast, and Nova Scotia, Canada. Results show considerably lower uncertainty and a more pronounced weakening of the AMOC.
“This represents the strongest direct observational evidence to date of AMOC weakening, aligning with long-held model predictions,” commented Stefan Rahmstorf from the University of Potsdam in Germany, who was not involved in the study.
Scientists speculate that freshwater from the melting Greenland ice sheet is diluting the AMOC’s intensely salted waters, impeding their sinking action and thus weakening the southward flow along the ocean floor of the western Atlantic. The observed declining trends across four latitudes in the Western Atlantic point to this phenomenon.
“We anticipate these changes to be evident deep within the western boundary,” team members assert, including David Smeed from the UK National Marine Centre. “This strengthens our confidence in that interpretation.”
“They provide the first robust evidence of a consistent weakening of overturning across various latitudes in the Deep West,” claims René van Westen, a professor at Utrecht University in the Netherlands, who did not participate in the study.
Elipot emphasized the need for ongoing observations to clarify whether the AMOC is on the brink of collapse, a scenario that could lead to significantly colder winters in Europe and disrupt monsoon patterns in Asia and Africa.
“This trend suggests we might be approaching a tipping point,” he notes.
Topics:
This version includes SEO-friendly keywords and phrases while maintaining clarity and readability. The HTML structure is preserved for use in a web context.
At dusk, a massive transfer of biomass occurs in the oceans, as trillions of tiny creatures like zooplankton, krill, and lanternfish rise from the depths, drawn by phytoplankton blooms. This nocturnal feeding frenzy is crucial for marine ecosystems, as these creatures avoid predators who hunt visually, diving back down at dawn.
Solar and lunar cycles dictate marine behavior, yet recent observations show that large areas of the ocean have darkened. Tim Smith, a marine scientist at the Plymouth Marine Research Institute, has been at the forefront of this research, studying the impact of global warming and land-use changes on ocean light dynamics.
Smith told New Scientist about the causes and implications of ocean darkening, exploring ways to enhance light penetration into underwater habitats.
Thomas Luton: How did you first notice the darkening of the ocean?
Tim Smith: We approached this issue from a unique perspective. For the last decade, I’ve collaborated with Tom Davis, focusing on the effects of artificial light pollution. Analyzing two decades of global satellite data revealed a consistent darkening pattern in the ocean, suggesting an increase in surface water opacity which affects well-connected expansive regions rather than isolated patches. About one-fifth of the world’s oceans have experienced some form of darkening.
What causes ocean darkening?
In coastal areas, river changes significantly impact ocean coloration. Alterations in land use directly influence what enters rivers, thereby transforming the optical properties of ocean water. Flood events can greatly increase the influx of suspended particulates and colored dissolved organic matter, contributing to the characteristic “steeped tea” color.
An additional driver of ocean darkening is nutrient loading, where fertilizers from agricultural runoff stimulate phytoplankton growth, reducing light penetration. Although coastal waters have been recognized as darkening for some time, the phenomenon is now extending into the open ocean.
Tim Smith studies the impact of land-use change and global warming on ocean dynamics.
Krave Getsi
What factors lead to changes in the open ocean?
These changes may correlate with the abundance of phytoplankton driven by climate change, such as rising ocean temperatures and increasing frequency of marine heatwaves. Climate alterations influence vast ocean circulation patterns significantly.
The proliferation of phytoplankton relies on a mix of light, nutrients, temperature, and water column dynamics. In winter, storms typically mix the ocean, but as spring arrives, a stable surface layer forms. These layers limit vertical mixing and enhance light and nutrient concentration, fostering phytoplankton growth.
I suspect that we’re witnessing a complex interplay between shifts in global circulation patterns and localized weather phenomena, such as clearer skies that promote phytoplankton growth. This combination may contribute to the widespread darkening of the open ocean.
What impacts does ocean darkening have on marine ecosystems?
To understand this better, consider the ocean’s food chain. Phytoplankton, the primary producers, experience the first effects of darkening. The next tier includes zooplankton, like Calanus copepods, which serve as a critical link in the food web and engage in diurnal vertical migration, moving up and down daily for feeding.
Zooplankton are a key component in the food web adversely affected by ocean darkening.
Flor Lee/Getty Images
During the day, they dive to depths of 200 to 300 meters where light is scarce, eluding visual predators. By night, they ascend in search of food. This behavior represents the largest biomass transfer on Earth, as millions of zooplankton migrate invisibly through the water, significantly outnumbering the terrestrial migrations like the Serengeti wildebeest.
What occurs when light cannot penetrate deep underwater?
The existence of dark regions in the ocean restricts the vertical habitat for species, which could lead to heightened competition for food and space. Some species may expend less energy hunting, impacting predation dynamics and thus altering food webs and global fishery productivity.
Fish species that rely on sight, including both small schooling fish and large predators like tuna, will find their hunting zones confined to the shallows. Simultaneously, phytoplankton may face altered depths for photosynthesis due to decreasing light availability.
Is nighttime ocean darkness still a concern?
Absolutely. Beyond sunlight, moonlight plays a crucial role in nocturnal migrations of many marine creatures. While the ocean appears nearly black at night to humans, the moon’s dim glow has significant implications for guiding species during foraging and return to deeper waters.
Our lunar models indicate that as ocean clarity decreases, moonlight’s penetration diminishes, which may compress the nighttime habitat, dramatically shifting ecological interactions in darkness.
What is the global impact of these changes?
Ocean darkening could profoundly affect the carbon cycle as well. If zooplankton cannot dive as deeply to evade predators due to limited light, their efficiency in pulling carbon from the atmosphere diminishes. When zooplankton perish, they normally sink and trap carbon deep in the ocean; without the ability to dive, much of this carbon may remain in the upper layers, ready to be re-released into the atmosphere.
However, assessing how carbon moves from the illuminated surface to the ocean floor remains complex. Satellite data provides a global perspective, but it offers only a glimpse into dynamics at work.
Is there a way to combat ocean darkening?
In certain areas, yes. Coastal waters are especially vulnerable to terrestrial activities, particularly agricultural runoff. By managing land better, including practices such as reducing fertilizer usage, we could restore some clarity to coastal waters. Initiatives like the AgZero+ program led by the UK Center for Ecology and Hydrology encourage collaborative efforts with farmers to develop eco-friendly farming techniques, thereby minimizing runoff and enhancing water quality. Strategies like improved fertilizer management and agroforestry could substantially mitigate the darkening of coastal waters.
Nevertheless, addressing the drivers of darkening in the open ocean is far more challenging. Even if global emissions halt immediately, ecological responses would take decades, potentially centuries.
Is there hope for the seas?
Absolutely. Evidence shows that marine environments can exhibit remarkable resilience when given a chance. Protected marine ecosystems can recover swiftly. For instance, kelp forests off California rebounded rapidly in well-managed reserves after a severe marine heatwave between 2014 and 2016.
This resilience has led to a global push to expand marine protected areas, which can act as ecological refuge zones, helping to rebuild vital marine life and restore ecological equilibrium. Such measures are crucial in the face of climate stressors like heatwaves.
There is optimistic news: the ocean exhibits extraordinary self-repair capabilities. With adequate protection and time, marine ecosystems can respond swiftly, crucial for all life on Earth. The oceans, covering about 70% of the planet, play a significant role in climate regulation and carbon absorption, underscoring the need to protect this invaluable life-support system.
New research on two 240-million-year-old coelacanth fossils reveals an intriguing sensory adaptation: ossified lungs that transmit sound to the inner ear, shedding light on how early vertebrates interpreted their environment.
Reconstruction of a Triassic coelacanth. This schematic illustrates the connection between ossified lungs and the inner ear, enabling underwater hearing. Image credit: A. Beneteau & L. Cavin, MHNG.
“Coelacanths are lobe-finned fish with a rich fossil history exceeding 400 million years, offering crucial insights into vertebrate anatomical evolution,” said Professor Lionel Cavin, a paleontologist affiliated with the Natural History Museum of Geneva and the University of Geneva.
“Once believed extinct, the genus Latimeria remains, currently including two recognized species.”
“Fossilized coelacanths possess a series of large, puzzling ossified plates arranged in a tiled pattern within their body cavities, surrounding an internal area that likely contained gas during life.”
In a groundbreaking study, paleontologists investigated the lungs and inner ear anatomy of two Middle Triassic coelacanth species: Glauria Branchiodonta and Loreleia eusingulata from eastern France.
By utilizing a particle accelerator at the European Synchrotron Radiation Facility, researchers uncovered an exceptionally well-preserved ossified lung featuring wing-like bony structures at its tip.
Simultaneously, examinations of modern coelacanth embryos revealed canals linking auditory and balance organs on either side of the skull.
By synthesizing these findings, researchers propose that these structures create a comprehensive sensory system.
Sound waves captured by the ossified lungs are believed to be conveyed through this channel to the inner ear, enhancing the animal’s underwater auditory perception.
“Our hypothesis draws parallels with contemporary freshwater fish like carp and catfish,” explained Luigi Manueli, a PhD student at the Geneva Museum of Natural History and the University of Geneva.
“In these fish, a structure known as the Weber apparatus links the swim bladder to the inner ear, facilitating the detection of underwater sounds.”
“Air pockets in the swim bladder are vital for sensing these waves; otherwise, they would go unnoticed by the fish.”
“This hearing capability likely diminished as modern coelacanth ancestors adapted to deep-sea settings, leading to lung degeneration and the obsolescence of this system,” noted Professor Cavin.
“Remarkably, some structures related to the inner ear remain preserved.”
“These anatomical remnants offer valuable insights into the evolutionary trajectory of these fish and potentially our own aquatic ancestors.”
For more details, refer to the study published in the Journal on February 14, 2026, in Communication Biology.
_____
L. Manueli et al. 2026. The dual functions of coelacanth lungs: breathing and hearing. Commun. Biol. 9, 400; doi: 10.1038/s42003-026-09708-6
Credit: Sebnem Coskun/Anadolu Agency via Getty Images
Recent scientific discussions have centered on the unexpected decline of Antarctic sea ice, which was previously considered resistant to climate change. Research indicates that robust winds have stirred warmer deep ocean water, disrupting the protective layer above the ice, leading to its accelerated melt.
While Arctic sea ice has seen a dramatic decrease of approximately 40% over four decades, Antarctic sea ice had shown slight expansion until recent trends reversed this. Since 2015, the extent of sea ice has shifted from record highs to remarkable lows, akin to the area of Greenland.
According to a study conducted by Antarctic researchers, rising temperatures are primary contributors to this melting. Further investigations reveal that ocean warming has played a pivotal role in this significant ‘regime shift’.
As stated by Simon Georgie from the National Marine Center in Southampton, UK, “A thorough analysis reveals a convincing sequence of events where oceans have significantly impacted ice melting, particularly starting in 2016.”
The circumpolar deep water, a warm, salty ocean body, flows southward from tropical regions, encircling Antarctica at depths under 200 meters. Two decades of temperature and salinity data suggest that this warm water is gradually surfacing, contributing to sea ice melt.
Antarctica is flanked by intense winds and storms in the “Roaring 40s,” “Roaring 50s,” and “Screaming 60s.” Climate change is shifting these storm paths southward, increasing precipitation in sea ice regions. Earl Wilson and colleagues from Stanford University highlight that additional precipitation formed a fresh water layer on the surface, temporarily insulating the sea ice from the warmer waters below.
However, these southward-moving storms bring strong winds that push surface water and ice forward. The Earth’s rotation causes this water to disperse at a right angle to the wind direction, facilitating a vortex comparable to the Weddell Sea circulation. As surface water shifts away, deep water replaces it, promoting further ice melt.
From 2014 to 2016, the upwelling of deep water began to outweigh the insulated layer of fresh water created by precipitation. This was evidenced in a simple computer model that mimicked real-world ice expansion and contraction based on observed temperature and salinity changes.
“Indications suggest a continued decline in sea ice,” Wilson remarks. “Although precipitation may reduce deep-sea heat temporarily, that heat remains a factor. A sudden change in conditions could unleash it back into the environment.”
A follow-up study indicates this reversal was instigated by a sequence of storms. Theo Spira and his team at the Alfred Wegener Institute in Germany found that the intrusion of warmer deep waters, coupled with winter water effects, is exacerbated by increasingly warmer global temperatures.
This warming causes deep water expansion, reducing winter water thickness, and has resulted in flooding of deeper waters over time. Since 2015 and 2016, strong winds have exacerbated these conditions, without allowing the lamellar structure to stabilize.
Importantly, while wind patterns may be a natural phenomenon, global warming has set the stage for these changes, as noted by Spira, emphasizing that the ocean’s reactions to these winds might mitigate the rapid ice decline.
Although melting sea ice will not directly contribute to rising sea levels, it poses risks to species such as krill and penguins that rely on this ice for habitat. Additionally, if sea ice retreats near significant ice shelves, it may disrupt global ocean currents, including the Atlantic meridional overturning circulation critical for maintaining Europe’s climate.
“The reduction of sea ice formation in these areas could lead to diminishing bottom water and decrease the meridional overturning circulation,” explains Wilson, while acknowledging that freshwater from glacier melt has a more pronounced impact on these dynamics.
It’s astonishing that we have more detailed maps of the moon than of our deep ocean floor. The moon’s surface is easier to observe, as it lacks the vast deep ocean that obscures our view of Earth’s underwater terrain.
With a telescope on a clear night, anyone can glimpse the moon’s features, especially on the side visible from Earth. Interestingly, the moon is roughly one-tenth the size of the deep ocean floor, which encompasses two-thirds of our planet’s surface.
The deep ocean covers an extensive area of over 335 million square kilometers (approximately 129.3 million square miles). Its inaccessibility, combined with the vastness of the ocean, explains why, despite our advanced technology, only a fraction has been explored.
Recently, a dedicated team of scientists compiled a comprehensive dataset containing data from around 44,000 dives into the deep ocean. These dives were conducted using submarines, remotely operated vehicles (ROVs), and autonomous underwater robots.
These deep-diving vehicles have collectively documented less than 0.001% of the deep-sea floor, comparable to the area of Rhode Island, the smallest U.S. state. If we applied similar statistics to terrestrial exploration, our entire understanding of ecosystems would come from an area only as large as the London metropolitan region.
Moreover, the minuscule part of the ocean floor studied is a highly biased sample. In fact, 65% of deep-sea exploration dives happened within 200 nautical miles of the United States, Japan, or New Zealand. Nearly all deep-seafloor observations (around 97%) were conducted by these three countries, in addition to France and Germany.
ROVs map the landscape from above, revealing the terrain and its inhabitants – Photo credit: NOAA Ocean Exploration
Additionally, explorers have mainly concentrated on a narrow spectrum of deep-sea features, dedicating significant research to rugged marine landscapes such as deep canyons and cliffs while neglecting regions like the expansive abyssal plains.
The Global Dive Dataset also highlights a critical limitation: dive depth. While the number of dives has increased over the decades, the depths have generally become shallower. In the 1960s, over half of dives surpassed 2 km (about 1.2 miles) deep, but by the 2010s, only a quarter of dives reached that depth.
This is concerning because approximately 75% of the ocean lies between 2 km and 6 km (1.2 miles and 3.7 miles) beneath sea level, indicating that significant portions of the ocean floor remain uncharted.
Clearly, contemporary deep-sea explorations overlook vast areas, leaving much of the ocean unexplored and unknown. Various initiatives are underway to enhance access to deep-sea tools and dive into less-known locations to discover what lies beneath the global deep ocean.
This article responds to Charlotte Preston of Southampton, who asked: “How much of the ocean floor have we actually explored?”
For more fascinating science insights, check out our Ultimate Fun Facts page.
The ongoing northward shift of the Gulf Stream indicates a concerning trend: the weakening of the ocean current system crucial for keeping Europe warm. Recent models suggest that unexpected changes in the Gulf Stream may signal an imminent catastrophic collapse of this vital current.
The Atlantic Meridional Circulation (AMOC) is a flow of warm, salty surface water originating in the tropics, moving towards northwest Europe, where it cools, sinks, and returns south along the ocean floor. Specifically, the Gulf Stream is the component that travels from the Gulf of Mexico up the East Coast of the United States, redirecting eastward into the Atlantic Ocean.
As the Greenland ice sheet continues to melt, it releases fresh water into the North Atlantic. This dilution is expected to hinder AMOC’s strength, as the less salty water affects the sinking and southern flow of this essential current. While some studies indicate this phenomenon is already in effect, clear evidence remains elusive.
Recent research led by René van Westen and Henk Dykstra, both affiliated with Utrecht University in the Netherlands, reveals that the weakening of AMOC is altering the Gulf Stream’s path, causing it to shift further north along the U.S. coastline before veering back into the Atlantic Ocean.
The findings demonstrate that the Gulf Stream has already shifted approximately 50 kilometers north over the past 30 years, as indicated by satellite data.
“This shift is measurable,” Van Westen stated. “As a result, it is very likely indicative of AMOC’s weakening.”
Historical reconstructions that estimate the AMOC discharge based on ocean temperatures indicate a 15 percent reduction since 1950. However, monitoring of actual ocean flows began only in 2004, insufficient to determine if the observed changes are natural variations or accelerating trends.
“We’re exploring alternative methods, such as analyzing the Gulf Stream’s pathway,” Van Westen remarked.
The study employs a model with 10-kilometer resolution, rather than the standard 100-kilometer resolution, facilitating the examination of the bulge responsible for the significant volume of water transported by the Gulf Stream.
The trajectory of this bulge varies as one of AMOC’s tributaries, the Deep Western Boundary Current, transports cold saline water southward along the ocean floor. Typically, this current flows below the Gulf Stream, exerting a pull that moves the Gulf Stream southward. However, as AMOC weakens, the Deep Western Boundary Current diminishes as well, leading to a gradual northward shift of the Gulf Stream.
In simulation scenarios extending 392 years into the future, the Gulf Stream is projected to leap more than 200 kilometers northward in a mere two years, followed by the collapse of AMOC two and a half decades later. Previous studies indicate that such a collapse could lead to severe climate consequences, such as a -20°C (-4°F) cold wave in London and an extreme -48°C (-54°F) temperature in Oslo, Norway.
This modeling represents an idealized scenario and does not predict that AMOC will collapse in 400 years. Nevertheless, it does highlight that a rapid shift in the Gulf Stream could serve as an early warning for an impending AMOC closure—a unique early indicator available to us. By that point, it may be too late to averting AMOC collapse, but proactive measures, such as enhancing home insulation and exploring agricultural areas further south, could be taken by Europe.
“We now possess effective early warning indicators that can be quantified,” Van Westen asserts. “This is straightforward to measure.”
Nonetheless, the timeline for AMOC’s potential collapse following Gulf Stream changes remains uncertain. Predictions for AMOC closure vary significantly, ranging from decades to centuries.
Dan Seidoff, a retired oceanographer with the National Oceanic and Atmospheric Administration, cautioned that fresh water from Greenland could impact AMOC at a rate and location different from model predictions.
“Critical questions remain about when, how, and why AMOC changes might occur,” he explained. “If changes follow the model’s predictions, it could serve as a precursor indicating Gulf Stream shifts and issue warning signals.”
While the correlation between abrupt changes and AMOC collapse must be validated by additional models, this study strengthens the case that AMOC is indeed experiencing a slowdown, according to Stefan Rahmstorf of the University of Potsdam, Germany.
“The slowdown seems to be happening at a pace faster than predicted in global warming scenarios,” he noted. “Current climate models may not adequately capture the urgency of this issue, potentially altering estimations regarding when the AMOC tipping point will occur.”
Artwork of Hibodus sharks—predators from the late Permian period that outlasted mass extinctions.
Credit: Christian Darkin/Science Photo Library
The largest mass extinction in history led to the loss of over 80% of marine life. Remarkably, certain ecosystems continued to thrive, and various species, including apex predators, managed to survive this catastrophic event.
This research indicates that the survival of specific ecosystems was influenced by their unique species compositions. A similar pattern may be observed in today’s marine ecosystems, which are under significant threat from climate change.
Approximately 252 million years ago, the end-Permian extinction was likely triggered by extensive volcanic eruptions in present-day Siberia, causing rapid global warming and diminishing ocean oxygen levels. Notably, some groups, like trilobites and eurypterids (sea scorpions), faced total extinction, while others experienced dramatic losses. In the aftermath, new species groups emerged, including dinosaurs and ichthyosaurs.
Despite the extinction of numerous species, researchers speculate that ecosystems may have become less complex. A functioning ecosystem relies on diverse interdependent species—plants that produce energy, herbivores that consume them, and predators that eat herbivores. Top predators may face extinction as they depend on prey for survival. Thus, a significant extinction event, such as the one at the end of the Permian, would simplify ecosystems.
To investigate this hypothesis, Baran Kalapunar and a team from the University of Leeds assessed preserved remains from seven marine ecosystems globally, both before and after the extinction. They analyzed the ecosystem structures based on the species present. Kalapunar declined to provide an interview as the study is yet to undergo peer review.
Even with species losses reaching 96%, five of the seven ecosystems sustained at least four trophic levels.
In regions, particularly near the poles, slow-moving herbivores caused the most significant damage, while free-swimming organisms, such as fish, were less severely impacted.
Ecosystem recovery varied based on proximity to the equator. Tropical ecosystems were primarily populated by low-trophic-level species, while those nearer to the poles experienced the addition of trophic levels as fish predators relocated away from extreme heat near the equator.
These findings imply that present-day marine ecosystems also respond differently to climate change and other anthropogenic impacts.
“I’m not aware of any other study that encompasses so many regions,” states Peter Roopnarine from the California Academy of Sciences in San Francisco. He concurs with the conclusions that many ecosystems sustain trophic levels despite extinctions, as previous smaller-scale studies indicated.
However, Roopnarine cautions against placing too much emphasis on the specifics of researchers’ ecosystem models. The fossil record does not clarify which organisms survived and which did not, requiring researchers to combine all photosynthetic organisms together without predicting outcomes if these species became extinct. “These findings are firmly supported by the fossil record, yet it remains incomplete,” he remarks.
Dinosaur Fossil Discovery in Mongolia’s Gobi Desert
Join an exciting expedition to unearth dinosaur fossils in Mongolia’s Gobi Desert, one of the world’s top paleontological locations.
An oil spill at sea represents one of the worst man-made disasters in history. Surprisingly, introducing a fire whirlpool may emerge as an innovative solution. A recent study reveals it might be an effective method to address the aftermath.
In responding to significant oil spills, emergency teams often ignite oil slicks on the ocean surface, creating fire pits “on-site” to curb the further spread of oil.
While this approach helps protect marine ecosystems, it simultaneously releases substantial amounts of smoke and toxic soot into the atmosphere.
The inspiration for this method traces back to an unusual incident in Kentucky in 2003, where a bourbon spill ignited 800,000 gallons, creating a 30-meter (100-foot) firestorm over a lake. Professor Elaine Oran and her team began exploring whether this process could be utilized more permanently.
“We were joking about what it would smell like,” she shared with BBC Science Focus. “Then we examined the event closely. The larger fire vortex was effectively consuming smaller fire vortices, drawing them in and absorbing them.”
The team constructed a 4.8-meter (16-foot) triple-walled triangular structure at a fire training facility in Texas, featuring a pool of crude oil at its center. When ignited, this setup created a roaring fire vortex approximately 5.2 meters (17 feet) high.
Initial large-scale experiments demonstrate that fire vortices burn spilled oil faster and cleaner than traditional fire pools, showcasing innovative potential for ocean cleanup. – Photo credit: Texas A&M University College of Engineering
Compared to conventional fire pools, the oil burns 40% faster, soot emissions are reduced by 40%, and up to 95% of the fuel is consumed.
The secret to this efficiency lies in the fire’s spin. Instead of spreading outward, the vortex pulls in oxygen from all angles, allowing for hotter and more complete combustion, akin to a giant incinerator rather than a simple bonfire.
However, harnessing this fire whirlpool’s power is no easy task. The structure is unpredictable; too much wind can lead to its collapse, while insufficient airflow control may revert it to a traditional fire pool.
Nonetheless, achieving a “Goldilocks Zone” on-site is “very realistic,” according to Oran, who envisions deploying a movable barrier structure directly above oil spills at sea.
“This research is more than just an experiment; it offers a glimpse into a future where fire is not merely a destructive force, but a tool to safeguard our oceans and our planet,” she stated.
For those captivated by extraterrestrial news, if you’re an avid reader of New Scientist, you might be aware of recent discoveries hinting at life’s potential on distant planets. Perhaps you’ve heard about a Mars rover uncovering signs of ancient life in uniquely patterned rock or recalled that moment last year when an asteroid appeared to threaten Earth.
While these cosmic revelations are undoubtedly thrilling, they often quickly dissolve into distant echoes, overshadowed by pressing global matters like conflicts and climate crises. The chance of alien microbes emitting gases from a planet trillions of kilometers away may ignite your imagination for a fleeting moment, but what real significance do these cosmic findings hold for our lives on Earth?
Climate historian Dagomar DeGroot argues that our fascination with the cosmos has profoundly shaped human history in his new book, Ripples in the Cosmic Ocean: How the Solar System Shaped Human History – and Might Save the Planet.
“
Venus’ runaway greenhouse effect prompts the question: could Earth face a similar fate? “
Although DeGroot may not be a scientist, he represents a new generation of interdisciplinary historians, serving as an environmental historian at Georgetown University.
His book delves into how shifts in the cosmic environment have influenced human events, drawing from archives of renowned and obscure scientists alike to construct a detailed narrative of scientific advancement. DeGroot argues for the need to observe our surroundings with a cosmic lens: “We cannot deny the existence of the ocean, both because its waves reach us without us seeking them, and because only by gazing into the abyss can we truly comprehend our isolated island.”
Our understanding of Earth’s climate, past ice ages, and potential global warming would be drastically diminished without our planetary neighbors illuminating the night sky. Recognizing the challenges posed by existential threats such as nuclear conflict and catastrophic asteroid impacts is crucial. Furthermore, we could find ourselves embroiled in theological disputes over heliocentrism.
DeGroot highlights the impactful influence a single planet can possess. For instance, Venus is depicted as a hostile environment with temperatures soaring above 460 degrees Celsius and active volcanoes releasing sulfur dioxide.
This perception has evolved. Initially, astronomers faced difficulties in observing Venus due to its dense atmosphere, yet by the 19th century, many agreed on the existence of cloud cover.
This misinformation fueled speculation about a habitable world under its clouds, significantly contributing to the rise of cosmic pluralism—the idea that Earth is not the sole cradle of life.
As our observational equipment improved and the harsh reality of Venus was unveiled, urgent questions emerged: Is this a warning for Earth’s future?
Understanding Venus’ extreme temperatures caused by a runaway greenhouse effect raises concern about the possibility for Earth to face a similar crisis. Numerous scientists, including astronomer Carl Sagan and climatologist James Hansen, dedicated their careers to studying Venus, which in turn sparked serious warnings about climate change on Earth.
DeGroot’s book overflows with instances like these, illustrating how Martian dust storms have compelled scientists to consider the ramifications of nuclear conflict. In 1994, the spectacle of comet Shoemaker-Levy 9 colliding with Jupiter emphasized the urgency of defending Earth against similar threats.
Ripples in the Cosmic Ocean captivates readers with its exploration of lesser-known tales in the history of scientific ideas, showcasing peculiar and vibrant figures. One such figure is Immanuel Velikovsky, an American-Russian psychoanalyst whose peculiar theories about Venus generated intriguing predictions but also controversy within the scientific community from the 1950s to the 1970s.
Ripples in the Cosmic Ocean
DeGroot compellingly makes the case for looking beyond our world, yet he admits that navigating future space exploration and observations presents challenges. We now live in a time of remarkable space exploration, notably advanced by billionaire-funded companies like Elon Musk’s SpaceX and Jeff Bezos’ Blue Origin.
He argues for an alternative approach that avoids exploiting space solely for affluent interests. Historically, colonial powers exploited knowledge for empire expansion. In a refreshing perspective, DeGroot suggests that we should foster life on Earth and cultivate “a vision of the ocean that creates and sustains communities in the cosmos for the collective benefit of all.”
One of his innovative ideas involves generating solar power from space, such as deploying solar panels on the moon to transmit energy back to Earth. Although the feasibility of such projects remains debatable, DeGroot underscores the necessity of choosing a path forward. Drawing from our solar system’s historical influence, he states, “Humanity’s journey has been partly driven by ripples in the cosmic ocean. Regardless of our actions, new waves will approach. Now, we hold the power to create our own waves. Our future may hinge on how we choose to shape those waves.”
3 Must-Read Books on the Solar System
Pale Blue DotA Vision of Humanity’s Future in Space Carl Sagan Astronomer Carl Sagan explores the significance of our solar system in shaping human understanding and our place in the universe in this evocative meditation.
Space War H.G. Wells This classic features prominently in DeGroot’s book (see main review), recounting the famous radio adaptation that led to widespread panic among listeners who believed Earth was truly under Martian threat.
Mars City Kelly Weinersmith & Zach Weinersmith
This dynamic duo, a cartoonist and biologist, explores the harsh realities of life on Mars through scientific facts and beautiful illustrations, revealing the challenges of living beyond Earth.
When you envision the North Pole, you likely imagine a vast, icy wonderland devoid of life. Noise might be the last thing on your mind.
However, recent findings from a study published in npj Acoustics reveal that the underwater soundscape is far more expansive and diverse than we previously thought. This raises crucial questions about how to monitor and protect this unique environment.
Analyzing a decade’s worth of underwater sound data from Cambridge Bay in the Canadian Arctic, researchers discovered that climate change is accelerating ice loss, reshaping the region’s underwater soundscape—an alteration that could have serious ramifications for local wildlife.
“Climate change is more than tripling in the Arctic, which means ice is melting faster, melting earlier, and reforming later,” stated Dr. Philippe Blondel, the lead author of the study and a senior lecturer in the Department of Physics at the University of Bath, UK, in an interview with BBC Science Focus.
“As a result, the Arctic becomes more accessible for human activities. Navigation becomes easier for ships in an ice-free environment. A key finding from our research is that while ships generate noise, they are not the only contributors.”
The study identifies that not only large ships—often the focus of noise pollution regulations—but also other significant sources such as snowmobiles, aircraft, and smaller vessels contribute to underwater noise. Many of these smaller noise sources evade detection by satellite systems, leading to gaps in models that rely solely on vessel position data.
Vital Arctic species, including whales and seals, depend on sound for communication, navigation, finding food, and evading predators. With increasing underwater noise both in frequency and volume, these essential communication tools are increasingly compromised.
Whales rely on sound production and hearing for survival – Photo courtesy of Getty
Dr. Blondel likens the situation to standing next to a busy freeway. “You might only hear the ambient noise, but when a motorcycle rushes by, that high-frequency noise disrupts your ability to hear music.”
“When a large truck thunders past, it becomes nearly impossible to hear anything else.”
In a similar manner, one sound source could disrupt a whale trying to communicate with its calves, while another noise at a different frequency might drive the whale away from critical feeding areas.
However, the research team is not advocating for total silence in the Arctic. Instead, Blondel proposes that environmental policies should encompass a broader array of frequencies beyond the narrow “transport bands” typically measured in protection frameworks, such as the European Maritime Strategy Framework Directive.
He recommends establishing stricter shipping routes in the increasingly ice-free Arctic and implementing varying speed limits depending on wildlife presence, as potential strategies to mitigate harmful noise pollution.
Yet, enforcing such regulations poses challenges, as they would need to encompass everything from large vessels to smaller crafts, and the region is bordered by multiple nations.
“My primary goal was to demonstrate that when assessing the ocean’s soundscape, we need to consider all sound sources, not just large ships,” Blondel emphasized. “But my overarching aim is to establish some form of framework in the Arctic. We must devise effective noise guidelines before the situation worsens further.”
Geophysicists from Washington State University and Virginia Tech have uncovered a potential pathway for nutrient transport from the radioactive surface of Jupiter’s icy moon, Europa, to its subsurface ocean.
Artist’s concept of the oceans of Jupiter’s moon Europa. Image credit: NASA/JPL-Caltech.
Europa is believed to host more liquid water than all of Earth’s oceans combined, but this vast ocean lies beneath a thick, ice-covered shell that obstructs sunlight.
This ice layer means that any potential life in Europa’s oceans must seek alternative sources of nutrition and energy, raising important questions about how these aquatic environments can support life.
Moreover, Europa is under constant bombardment from intense radiation emitted by Jupiter.
This radiation interacts with salts and other surface materials on Europa, producing nutrients beneficial for marine microorganisms.
While several theories exist, planetary scientists have struggled to determine how nutrient-rich surface ice can penetrate the thick ice shell to reach the ocean below.
Europa’s icy surface is geologically active due to the gravitational forces from Jupiter; however, ice movements primarily occur horizontally rather than vertically, which limits surface-to-ocean exchange.
Dr. Austin Green from Virginia Tech and Dr. Katherine Cooper from Washington State University sought inspiration from Earth to address the surface recycling challenge.
“This innovative concept in planetary science borrows from well-established principles in Earth science,” stated Dr. Green.
“Notably, this approach tackles one of Europa’s persistent habitability questions and offers hope for the existence of extraterrestrial life within its oceans.”
The researchers focused on the phenomenon of crustal delamination, where tectonic compression and chemical densification in Earth’s crust lead to the separation and sinking of crustal layers into the mantle.
They speculated whether this process could be relevant to Europa, especially since certain regions of its ice surface contain dense salt deposits.
Previous investigations indicate that impurities can weaken ice’s crystalline structure, making it less stable than pure ice.
However, delamination requires that the ice surface be compromised, enabling it to detach and submerge within the ice shell.
The researchers proposed that dense, salty ice, surrounded by purer ice, could sink within the ice shell, thereby facilitating the recycling of Europa’s surface and nourishing the ocean beneath.
Using computer simulations, they discovered that as long as the surface ice is somewhat weakened, nutrient-rich ice laden with salts can descend to the bottom of the ice shell.
This recycling process is swift and could serve as a reliable mechanism for providing essential nutrients to Europa’s oceans.
The team’s study has been published in the Planetary Science Journal.
_____
AP Green and CM Cooper. 2026. Dripping into destruction: Exploring the convergence of viscous surfaces with salt in Europa’s icy shell. Planetary Science Journal 7, 13; doi: 10.3847/PSJ/ae2b6f
Mars’ geological features reveal that the planet once hosted rivers and extensive coastlines, indicating it may have had vast oceans in its history. This discovery offers the most substantial evidence yet of Mars’ once vibrant blue landscape.
According to Ezzat Heidari, a geochemist at Jackson State University in Mississippi (who was not part of the study), “The existence of liquid water on Mars encompasses a wide array of topics including rain, rivers, lakes, and oceans.” In his view, this research highlights a significant factor: the ocean.
The research team, featuring planetary geologists like Ignatius Indy and geoscientists such as Fritz Schlunegger from the University of Bern, made groundbreaking discoveries using data from numerous spacecraft. This includes NASA’s Mars Reconnaissance Orbiter and the European Space Agency’s Mars Express and ExoMars Trace Gas Orbiter. The ExoMars spacecraft, equipped with a specialized Bernese Mars camera, has been instrumental in capturing high-resolution color images, which were crucial for this research.
“These sophisticated images help us identify subtle variations in surface materials that are invisible in black and white images,” Indy explains. Combined with topographical data from other orbiters, these tools transform into a “geological time machine,” providing a clearer glimpse of Mars’ geological evolution.
To explore Mars’ potential ancient water sources, the researchers scrutinized Valles Marineris, an extensive canyon system over 4,000 kilometers long that runs along the planet’s equator. Their focus particularly emphasized the southeast area, Koprates Chasma, with its features dating back around 3.3 billion years.
By merging the new images with geomorphological analyses, the researchers identified structures indicative of river flow into oceans and the formation of alpine lakes at mountain bases—similar to Earth’s geography.
“The Nile Delta serves as a classic illustration,” Schlunegger notes. “If you were to drain the Mediterranean just past the end of the Nile, you’d observe features remarkably akin to those found on Mars,” he states.
Silty Deposits Left by Ancient Water on Mars
Algadestia et al. 2026, CaSSIS
The new data allowed scientists to trace the ancient coastline of Mars’ former ocean, estimating its size to be comparable to Earth’s Arctic Ocean. This could represent the largest ocean that ever existed on Mars.
“Our research indicates that approximately 3 billion years ago, Mars may have sustained significant bodies of surface water within Valles Marineris, the largest canyon in our solar system,” Indy remarked. “What’s even more intriguing is that these water bodies might have been linked to a much larger ocean that once spanned parts of Mars’ northern lowlands.”
While past research suggested the presence of water on Mars, much of the evidence was indirect. A notable study revealed Martian minerals that may have interacted with water long ago. Additional investigations have indicated that an ancient asteroid impact could have triggered a massive tsunami on the planet. Yet, acquiring conclusive data has remained a challenge.
The notion that Mars once harbored a vast ocean remains debated; as Michael Manga, a geoscientist from the University of California, Berkeley (who wasn’t involved in this study), points out, “Even if the ocean did exist, the geological record is far too ancient to be clear.”
This discovery raises fascinating possibilities for the search for extraterrestrial life and serves as a cautionary reminder that Earth’s crucial resources may also one day diminish.
“This paper addresses a question that is paramount to those researching Mars’ evolution,” Heidari said. “Martian oceans would have operated similarly to Earth’s oceans, playing a vital role in the planet’s health.”
World Capital of Astronomy: Chile
Discover Chile’s astronomical treasures, including the world’s most advanced observatory, and enjoy stargazing under the clearest skies on Earth.
Topics:
This rewritten content maintains the original HTML structure while optimizing for SEO with more relevant keywords and clarifications.
A groundbreaking treaty aimed at protecting the high seas has officially entered into force, marking a significant moment in marine conservation.
The vast expanses of the high seas, beyond a country’s 370-kilometre exclusive economic zone, are often referred to as the “Wild West” of the oceans. This region is notorious for its minimal regulations on fishing, making it a vital area that remains largely unexplored. According to recent studies, this deep-sea environment is inhabited by diverse marine organisms, with up to 95% of the habitat being vital to marine life.
In September 2025, over 60 countries ratified the UN Convention on the Conservation and Sustainable Use of Marine Biodiversity in the open ocean, which encompasses half of our planet’s surface. This historic agreement has initiated a 120-day countdown to its official implementation.
“This is one of the most important environmental agreements ever,” states Matt Frost from the Plymouth Marine Laboratory in the UK. “There was no established mechanism for creating protected marine areas on the high seas prior to this treaty.”
World-renowned marine biologist Sylvia Earle calls this treaty a ‘turning point’ in safeguarding ‘Earth’s blue heart’, which plays a crucial role in regulating climate and sustaining life.
A year remains before nations can establish protected areas under the treaty, as regulations and monitoring systems need to be finalized at the inaugural meeting of the parties in late 2026.
“This moment demonstrates that global cooperation is feasible,” says Earle. “Now we must act decisively.”
In the Atlantic, conservationists aim to safeguard unique ecosystems such as the “lost cities” formed by the seaweed mats of the Sargasso Sea, a crucial breeding ground for American and European eels, alongside the remarkable hydrothermal vent communities. Meanwhile, the Pacific Ocean conservation efforts target the Salas y Gomez and Nazca ridges, underwater mountains that serve as habitats for diverse marine species including whales, sharks, and turtles.
The treaty also envisions a shared repository for genetic resources discovered in the high seas, which could facilitate breakthroughs in medicinal research.
As maritime technology advances, fleets of factory ships are exploiting the high seas, leading to the overfishing of species and habitat destruction. This escalation threatens crucial biodiversity zones. Bottom trawling, in particular, causes severe damage to the ocean floor. Emerging techniques are being developed to fish in the “twilight zone” of mid-depth waters, between 200 and 1,000 meters, further complicating conservation efforts.
Local management organizations have noted that for two decades, there has been a call for a treaty to mitigate the overfishing of 56% of targeted fish stocks in international waters, as highlighted in recent studies.
Support for protective measures stems from the fact that 90% of marine protected areas in national waters are actively being preserved, positively influencing nearby fish populations by providing safe environments for spawning and growth.
Additionally, the 30 by 30 commitment aims to safeguard 30% of the Earth’s surface by 2030, making it essential to address the high seas for its successful realization.
Oceans currently absorb approximately 90% of the excess heat resulting from climate change. By shielding these critical areas from fishing and associated pollution, marine ecosystems can better adapt to rising temperatures.
“If you’re battling multiple afflictions, alleviating two can empower you to confront the remaining issues,” Frost asserts.
Moreover, marine ecosystems are responsible for absorbing a quarter of the CO2 emissions that contribute to climate change. Coastal environments like seagrass meadows and kelp forests are crucial carbon sinks, and activities such as the nocturnal feeding patterns of mesopelagic fish and plankton play a role in the carbon cycle.
“These species transport carbon from surface waters to deeper ocean layers, significantly influencing the carbon dynamics,” explains Callum Roberts from the Convex Seascape Survey, a global research initiative focusing on the ocean’s impact on climate change.
The treaty’s initial challenge involves identifying appropriate areas for protection, especially as species migrate in response to shifting ocean temperatures. Only 27% of the ocean floor has been thoroughly mapped.
Enforcement will also be a formidable challenge. Current marine protected areas in national waters include a significant number of “paper parks” that offer little actual protection for species.
Advancements in satellite imagery and AI technology have made it feasible to monitor vessels and detect unlawful activities. Nonetheless, enforcement will rely on member states to act against flagrant violations, including barring offending ships from their ports.
While 145 countries have signed the treaty, it is only enforceable for those that ratify it. Currently, 83 nations have adopted the treaty, with the UK, US, Canada, and Australia yet to follow suit.
“The more nations that ratify this treaty, the stronger it becomes,” says Sarah Bedorf from Oceana. “We all share the responsibility of protecting the high seas, which ultimately benefits everyone.”
Logging extensive areas of boreal forests and submerging the trees in the Arctic Ocean could potentially eliminate up to 1 billion tons of carbon dioxide from the atmosphere each year.
Researchers suggest cutting down wildfire-prone coniferous trees and transporting them through six major Arctic rivers, including the Yukon and Mackenzie, where they can sink within a year.
“Currently, we have forests that sequester significant carbon, but the next challenge is finding ways to store it without burning,” says Wolf Bungen from Cambridge University.
To combat carbon emissions from hard-to-electrify industries, it’s essential to explore methods for atmospheric carbon reduction. While direct air capture technology is costly, tree planting can backfire if the trees end up dying or burning.
Several companies are working on wood burial techniques. For instance, a U.S. initiative, Running Tide, sunk 25,000 tonnes of wood chips off Iceland’s coast but faced shutdown due to environmental concerns.
Approximately 1 trillion tonnes of carbon are stored within the wood, soil, and peat of boreal forests across North Eurasia and North America, a figure expected to rise as climate change accelerates plant growth. However, with increasing wildfire frequency, this carbon could be released.
Bungen and his team previously discovered that wood can survive for up to 8,000 years in cold, oxygen-limited Alpine lakes without decomposing or emitting CO2. Six Arctic rivers transport substantial amounts of logs, with driftwood in deltas estimated to contain over 20 million tons of carbon. Carl Stadie from Germany’s Alfred Wegener Institute was not part of the study.
If every year, 30,000 square kilometers were cleared along each river, placing the wood on river ice in winter and then replanting, it could absorb up to 1 billion tons of CO2 annually, researchers estimate.
However, some US rivers continue to experience biodiversity loss a century after timber removal, warns Ellen Wall of Colorado State University.
“Dumping a massive amount of logs into a river resembles pushing brush into a river,” she notes.
Moreover, if wood becomes lodged on beaches or in tributaries, causing flooding, it could thaw permafrost and increase methane emissions from microorganisms.
“We could see a scenario where the wood aids ocean carbon sequestration, while onshore flooding and melting snow cause carbon release at high altitudes,” warns Merritt Turetsky from the University of Colorado Boulder.
Inadequate cold or oxygen-free conditions may lead to wood decomposition rather than sinking. Driftwood frozen in sea ice is often transported to the Faroe Islands.
“In a worst-case scenario, vast forest areas could be cleared, impacting the carbon they store,” says Stadie.
Roman Dial, a professor at Alaska Pacific University, warns that this proposal may be exploited by commercial logging and could face criticism from all sides of the political spectrum.
“How extensive is the list of potential unintended consequences that could unfold in the Arctic, given our limited understanding?” he questions.
Some regions of the Arctic ocean floor might not be suitable for conservation, according to Morgan Raven at the University of California, Santa Barbara. However, others could benefit from exploration, given the substantial influx of wood into the Arctic and other oceans. The Earth once experienced a greenhouse climate era 56 million years ago.
“We can investigate sediments and rocks to understand how this experiment was conducted in the past,” Raven concludes.
Topics:
This rewrite optimizes the content for SEO while preserving the HTML structure and retaining the original message.
An in-depth analysis of the stresses, tides, and internal forces on Jupiter’s icy moon Europa indicates that the moon lacks the active submarine faults essential for robust hydrothermal circulation. This phenomenon significantly impacts Europa’s chemical energy and overall habitability.
A stunning view of Europa’s surface. Image scale is 1.6 km per pixel. North of Europa is on the right. Image credit: NASA / JPL-Caltech / SETI Institute.
On Earth, tectonic activity is crucial for supporting diverse habitats that sustain life.
This interaction between water and rocks on the ocean floor can generate chemical energy essential for potential biological processes.
Thus, the existence of tectonic activity on a celestial body can indicate an environment conducive to supporting life.
Europa, one of Jupiter’s moons, is believed to harbor an immense underground ocean beneath its frosty exterior.
While earlier studies hinted at volcanic activity beneath Europa’s ocean floor, the potential for tectonic movement had not been thoroughly explored until now.
“If we could survey those oceans using remote-controlled submarines, we predict we wouldn’t observe any new cracks, active volcanoes, or hydrothermal vents on the ocean floor,” stated Dr. Paul Byrne, a researcher at Washington University in St. Louis.
“Geologically, nothing is changing there. Everything remains quiet.”
“In icy worlds like Europa, a tranquil ocean floor could suggest a lifeless ocean.”
Dr. Byrne and his team conducted comprehensive modeling to evaluate potential tectonic activity within Europa’s theorized subsurface ocean.
Their findings were compared against known behaviors on Earth’s ocean floor and Enceladus.
The researchers assessed stress from tidal forces, global contraction, mantle convection, and serpentinization— a geological process involving the interaction of rocks and water.
However, they concluded that these factors are unlikely to be driving tectonic activity, even along Europa’s existing fissures at present.
This discovery implies that water-rock interactions might be confined to the uppermost layers of the ocean floor, which limits the prospects for habitable conditions beneath Europa’s surface.
Future research aims to gather direct evidence regarding Europa’s geology and tectonics.
“Europa likely experiences tidal heating, which is why it hasn’t fully frozen,” Dr. Byrne noted.
“There may have been greater heating in its distant past.”
“However, currently, we do not observe eruptions from the ice as seen on Io. Our calculations indicate that the currents are simply not strong enough to foster significant geological activity on the ocean floor.”
For more details, refer to the results published in this week’s issue of Nature Communications.
_____
PK burn et al. 2026. There may be little or no active faults on Europa’s ocean floor today. Nat Commune 17, 4; doi: 10.1038/s41467-025-67151-3
Europa, one of Jupiter’s intriguing moons, features a liquid ocean possibly encased beneath a thick layer of ice, estimated to be six times the depth of Antarctica’s icy crust, complicating our efforts to detect any potential lifeforms.
This moon is a leading candidate in the search for extraterrestrial life, primarily due to its significant volume of liquid water.
Previously, estimates regarding the thickness of Europa’s ice have varied dramatically—ranging from under 10 kilometers to nearly 50 kilometers. Researchers initially believed certain defects in the ice might permit nutrient exchange between the surface and the ocean below.
Now, a research team, led by Stephen Levin from the California Institute of Technology, has analyzed data collected by the Juno spacecraft, which has been orbiting Jupiter since 2016.
On September 29, 2022, Juno came within 360 kilometers of Europa, utilizing its microwave radiometer to scan the surface and perform the first direct measurements of the ice layer. Levin noted that this instrument assessed the heat emitted by Europa’s icy exterior, enabling the measurement of ice temperatures at various depths and detecting temperature fluctuations resulting from imperfections in the ice sheet.
The researchers estimate that the most accurate thickness of the ice sheet is approximately 29 kilometers, aligning with the higher range of previous estimates while presenting a possible thickness that could range from 19 kilometers to 39 kilometers.
Crucially, their findings indicate that the fissures, pores, and other imperfections likely extend only a few hundred meters beneath the surface, with pore diameters measuring only a few centimeters.
“This indicates that the observed defects in the microwave radiometers are insufficiently deep or expansive to facilitate significant nutrient transport between the ocean and the surface,” asserts Levin.
Nonetheless, this does not diminish the potential for life on Europa. Levin further explains, “Though the observed pores and cracks are too minute and shallow to transport nutrients, alternative transportation mechanisms may exist.”
There may also be unexplored regions of the moon where conditions differ, he adds.
Researchers including Ben Montet from the University of New South Wales in Sydney, express concerns that the ice thickness could hinder life’s search. “While this protection may sustain life for extended durations, it complicates our ability to penetrate the ice and study the ocean beneath,” he notes.
He argues that life could exist without a direct link between Europa’s surface and its subterranean ocean, though such a connection would enhance the chances of discovering life. Helen Maynard-Casley of the Australian Nuclear Science and Technology Agency emphasizes that without that transport link, “you’re essentially confined to whatever was in the ocean initially.”
NASA has plans to launch the Europa Clipper spacecraft in 2024, aiming to embark on its mission to Jupiter’s moons in 2030. This spacecraft is expected to provide clearer insights into Europa’s icy layer, according to Maynard-Casley.
Explore the Mysteries of the Universe: Cheshire, England
Join leading scientists for an engaging weekend as you unravel the mysteries of the universe alongside a tour of the legendary Lovell Telescope.
Data from NASA’s Cassini mission to Saturn initially suggested that Titan could possess a vast subterranean ocean of liquid water. However, when University of Washington scientist Baptiste Journeau and his team created models of a moon with an ocean, the findings did not align with the physical characteristics indicated by the data. What we likely observe instead resembles Arctic sea ice and aquifers, rather than an expansive ocean akin to those on Earth.
This composite image presents an infrared view of Titan. In this depiction, blue signifies wavelengths centered at 1.3 microns, green at 2.0 microns, and red at 5.0 microns. While visible wavelengths only reveal Titan’s hazy atmosphere, the near-infrared wavelengths enable Cassini’s vision to penetrate the haze, showcasing the moon’s surface. This perspective primarily focuses on the terrain in Titan’s hemisphere facing Saturn. Image credit: NASA / JPL-Caltech / Space Science Institute.
The Cassini mission, which commenced in 1997 and spanned nearly 20 years, yielded extensive data about Saturn and its 274 moons.
Titan is the only celestial body outside Earth known to feature liquid on its surface.
Temperatures on Titan hover around -183 degrees Celsius (-297 degrees Fahrenheit). Rather than water, liquid methane forms lakes and precipitates as rain.
As Titan orbits Saturn in an elliptical pattern, scientists noted the moon stretching or contracting based on its position relative to Saturn.
In 2008, they hypothesized that Titan must harbor a massive ocean beneath its crust to explain such notable deformation.
“The extent of deformation is influenced by Titan’s internal structure,” Journeau explains.
“When Saturn’s gravity acts on a deep ocean, it can bend the crust even more; however, if Titan is entirely frozen, the deformation would be less pronounced.”
“The deformations detected during the initial analysis of Cassini mission data might align with a global ocean scenario, but we now understand that there is more complexity involved.”
Schematic representation of Titan’s internal structure as revealed by Petricca et al.. Image credit: Petricca et al., doi: 10.1038/s41586-025-09818-x.
In this new study, Dr. Journeau and his co-authors introduce an additional layer of detail: timing.
Titan’s shape alteration lags Saturn’s peak gravitational influence by approximately 15 hours.
Similar to stirring honey with a spoon, manipulating a thick and viscous substance demands more energy compared to liquid water.
By measuring this delay, scientists were able to ascertain how much energy was required to alter Titan’s shape, facilitating inferences about its internal viscosity.
The energy loss, or dissipation, observed on Titan greatly exceeded what researchers anticipated in a global ocean framework.
“No one expected such significant energy dissipation to take place within Titan,” stated Dr. Flavio Petricca, a postdoctoral fellow at NASA’s Jet Propulsion Laboratory.
“This provided definitive evidence that Titan’s interior differs from our previous analyses.”
Consequently, the scientists proposed a model characterized by a greater presence of slush and significantly reduced quantities of liquid water.
This slush is sufficiently thick to explain the delay, yet still contains water, enabling Titan to deform under gravitational forces.
“Titan’s water layer is so dense and the pressure so great that it alters the physics of the water,” Journeau remarks.
“Water and ice behave differently compared to seawater on Earth.”
This study is published in today’s issue of Nature.
_____
F. Petricca et al. 2025. The dissipation of Titan’s powerful tidal forces prevents the formation of underground oceans. Nature 648, 556-561; doi: 10.1038/s41586-025-09818-x
Warm waters from the Atlantic near Greenland are now heating the deep layers of the Arctic Ocean, an area once considered relatively insulated from climate change.
The Arctic Ocean has seen a reduction of about 40% in its sea ice cover over the past 40 years, primarily due to the impact of atmospheric warming on sea levels. Researchers at the Ocean University of China evaluated the latest data collected by icebreakers to assess the temperature increase of the ocean floor.
In the Eurasian Basin, which is one of the ocean’s two principal sections, temperatures at depths ranging from 1500 meters to 2600 meters have increased by 0.074 degrees Celsius since 1990.
While this temperature rise may seem minor, it equates to nearly 500 trillion megajoules of energy. Such energy could potentially melt up to one-third of the least extensive sea ice area.
“The deep ocean is more dynamic than previously assumed,” states Chen Xianyao, one of the research team members. “We suspected that the deep ocean was warming, but not at this pace.”
An underwater ridge separating Greenland and Siberia divides the Arctic Ocean into two basins. The Amerasian Basin is primarily cut off from the Pacific Ocean by the shallow Bering Strait. However, warm Atlantic waters can still flow north along the Scandinavian coast into the upper Eurasian Basin through an extension of the Atlantic Meridional Overturning Circulation (AMOC). During winter, when seawater freezes, the salts are released, resulting in denser water that sinks and drags some warmer Atlantic water down with it.
Geothermal heat from the Earth warms the deep waters of the Eurasian Basin.
Previously, these warming trends were balanced by cold water flowing down from a neighboring basin east of Greenland. Yet, as the Greenland ice sheet continues to melt, more freshwater is entering the Greenland Basin. This influx has slowed the downward movement of cold, salty water, raising the temperature of deep waters in the Greenland Basin from -1.1°C to -0.7°C—a significantly rapid increase. Consequently, the influx of cold Greenland waters is no longer counteracting the heat from geothermal sources or the warm Atlantic waters sinking into the Arctic.
“The rising temperatures in the Greenland Basin are now reaching the Arctic,” says Son Louise, another research team member.
This research uncovers new warming mechanisms deep within the Arctic Ocean, “indicating a broader trend of global warming,” according to James McWilliams from UCLA.
The ongoing warming might eventually contribute to the melting of both sea ice and permafrost found on the ocean floor, which contains ice-like structures known as clathrates. If disturbed, these can release methane into the atmosphere, a phenomenon believed to have contributed to the Permian mass extinction.
The melting of Greenland’s ice sheet is predicted to hinder or disrupt the Atlantic current that helps keep Europe warm; however, meltwater from West Antarctica might help maintain this essential flow.
That said, it won’t be sufficient to prevent significant climate changes. The Atlantic Meridional Overturning Circulation (AMOC) is already down by 60% and could take up to 3,000 years to recover fully.
“I suggest caution in predicting an AMOC collapse,” states Sasha Sinnett from Utrecht University in the Netherlands. “However, my findings don’t alter what is forecasted for the next century. We may never see if West Antarctica successfully stabilizes the AMOC.”
The AMOC is a system of ocean currents that transports warm surface water from the tropics to northern Europe. Here, the water cools and sinks, then flows back south to Antarctica. This current carries an enormous amount of heat—1.2 petawatts—equivalent to the output of one million power plants, keeping Europe notably warmer than regions like Labrador or Siberia at similar latitudes. Lighter, fresher meltwater from Greenland is expected to obstruct the sinking of the denser, saltier AMOC water, thereby slowing its flow.
If the AMOC were to collapse, winter temperatures in Northern Europe could drop to almost -50℃ (-58°F). Recently, Iceland declared the closure of the AMOC as an “existing” security threat. Additionally, rising sea levels are threatening the U.S. East Coast, while Africa may face even more severe drought conditions.
A recent study indicates that even if we achieve net zero emissions by 2075 and begin reducing CO2 from the atmosphere, there is still a 25% risk of AMOC collapse. One study forecasts its closure in the coming decades, while another suggests that it will remain weakened due to Antarctic winds.
Currently, the melting of the West Antarctic ice sheet has accelerated, with some research indicating a probable complete collapse. However, the impact on AMOC remains uncertain.
The timing of the melting is crucial, according to simulations by Sinet and his team. If pulses of ancient Antarctic meltwater coincide with substantial meltwater from Greenland, the AMOC’s closure will be expedited.
Conversely, if the Antarctic water arrives about 1,000 years prior to the peak melting of Greenland, the AMOC may weaken for a few centuries but then recover over the next 3,000 years. While AMOC shows eventual recovery in all scenarios, early Antarctic melting prevents total collapse and accelerates its resurgence.
This phenomenon could be due to the relocation of the sinking, salty AMOC water moving south as lighter, fresher meltwater accumulates around Greenland, with the flow regaining strength as Antarctic melting decreases.
Though it’s improbable that West Antarctica melts at such a rapid pace while Greenland melts more slowly, these results illuminate a significant connection between AMOC and Antarctic ice melt, notes Louise Sim from the British Antarctic Survey.
“Prior to this study, the extent to which Antarctic changes could significantly influence the effects of Greenland’s ice sheet melting on the AMOC was largely unknown,” she remarks.
However, the study does not address potential feedback effects, such as shifts in wind patterns that might increase Antarctic sea ice, so this relationship needs to be explored in more complex models moving forward, she adds.
Even if rapid melting in West Antarctica prevents the AMOC from collapsing, it could still lead to sea-level rises of up to 3 meters, inundating coastal cities.
“Unfortunately, while one potential disaster may lessen the danger of another, this is little consolation,” concludes Stefan Rahmstorf from the University of Potsdam, Germany.
A plume of ice particles, water vapor, and organic compounds shooting from Enceladus’s southern polar area
NASA/JPL-Caltech
The hidden oceans of liquid water beneath Enceladus’ icy exterior have long positioned Saturn’s moon as a prime candidate in the search for alien life, and the prospects appear even brighter. Recent findings revealing heat from the frozen northern pole indicate that the ocean is stable over geological periods, allowing the potential for life to thrive.
“For the first time, we can assert confidently that Enceladus is in a stable condition, which has significant implications for its habitability,” states Carly Howett from Oxford University. “While we already knew about the presence of liquid water, a variety of organic molecules, and heat, stability was the crucial missing element.”
Howett and her team utilized data from NASA’s Cassini spacecraft, which orbited Saturn from 2004 to 2017, to analyze the heat leaking from Enceladus. The moon’s interior is warmed by tidal forces resulting from Saturn’s gravitational pull, but up to now, this heat had only been observed escaping from the south polar region.
A delicate balance is necessary for life to develop in Enceladus’s ocean. It’s essential for the ocean to emit as much heat as it receives. Although the recorded heat from the South Pole doesn’t account for all incoming heat, Howett and her colleagues discovered that the North Pole is approximately 7 degrees warmer than previously assumed. Together with the heat from the South Pole, the overall heat balance is nearly precise. Due to a thicker ice shell near the equator, a substantial amount of heat escapes primarily in the polar regions.
This indicates that the ocean must maintain stability over extended durations. “Quantifying this is challenging, but we don’t anticipate a freeze in the near future, nor have we seen one recently,” Howett explained. “We understand that life requires time to evolve, and now we can affirm that this stability exists.” Nevertheless, discovering life, if it indeed exists, presents its own challenges. Both NASA and ESA are planning missions aimed at unearthing such life for decades ahead.
Approximately 4.3 billion years ago, during the early formation of our solar system, a massive asteroid collided with the far side of the moon, resulting in the creation of the South Pole-Aitken Basin—an enormous crater. This feature, the largest on the moon, spans over 1,200 miles in length and 1,000 miles in width. Its rectangular shape is attributed to a glancing impact rather than a direct hit. Challenging previous beliefs that the basin was formed by an asteroid coming from the south, recent research indicates that the narrowing shape of the basin towards the south suggests an impact from the north.
The South Pole-Aitken Impact Basin on the far side of the Moon was formed by a southward impact. Image credit: Jeff Andrews-Hanna / University of Arizona / NASA / National Astronomical Observatory of Japan.
“The downstream edge of the basin should have a thick layer of material that was excavated from the moon’s interior by the impact, while the upper edge should not,” explained Dr. Jeffrey Andrews-Hanna, a planetary scientist at the University of Arizona.
“This suggests that the Artemis mission will target the downrange rim of the basin, an ideal site to examine the moon’s largest and oldest impact basins, where most of the ejecta, consisting of material from deep within the moon, are likely to be gathered.”
Historically, it has been believed that early moons were molten due to the energy released during their formation, resulting in a magma ocean that enveloped the entire moon.
As this magma ocean solidified, heavy minerals settled to create the Moon’s mantle, while lighter minerals floated upwards to form the Earth’s crust.
Nevertheless, certain elements were not incorporated into the solid mantle and crust, but instead became concentrated in the last liquid remnants of the magma ocean.
These “residual” elements, including potassium, rare earth elements, and phosphorus, are collectively known as KREEP.
Dr. Andrews-Hanna and his team noted that these elements appear to be especially abundant on the moon’s near side.
“If you’ve ever frozen a can of soda, you might have noticed that high fructose corn syrup doesn’t freeze all the way through and instead accumulates at the bottom of the liquid,” remarked Dr. Andrews-Hanna.
“We believe a similar phenomenon occurred on the moon with KREEP.”
“Over millions of years, as it cooled, the magma ocean crystallized into the crust and mantle.”
“Eventually, only a small amount of liquid remained trapped between the mantle and the crust, which is this KREEP-rich material.”
“The abundance of KREEP’s heat-producing elements somehow concentrated on the moon’s near side, causing it to heat up and initiate intense volcanic activity, thus creating the dark volcanic plains visible from Earth.”
“However, the process by which this KREEP-rich material became concentrated on the near side and how it evolved remains an enigma.”
“The moon’s crust is considerably thicker on the far side compared to the near side that faces Earth, a discrepancy that continues to puzzle scientists.”
“This asymmetry influences various aspects of the moon’s development, including the final stages of the magma ocean.”
“Our hypothesis posits that as the far side’s crust thickened, the underlying magma ocean was forced outward, akin to squeezing toothpaste from a tube, causing most of it to accumulate on the near side.”
A recent investigation of the Antarctic Aitken Basin has uncovered unexpected asymmetries supporting this scenario. The western ejecta blanket is rich in radioactive thorium, while the eastern side is not.
This indicates that the rift left by the impact formed a conduit through the moon’s crust, near the boundary separating the “normal” crust from the underlying layers that contain the final remnants of the KREEP-rich magma ocean.
“Our research shows that the distribution and composition of these materials align with predictions derived from modeling the later stages of magma ocean evolution,” stated Dr. Andrews-Hanna.
“The last remnants of the Moon’s magma ocean have reached the near side, where the concentration of radioactive elements is at its peak.”
“However, prior to this, there may have been a thin, patchy layer of magma ocean beneath parts of the far side, explaining the presence of radioactive ejecta on one flank of the Antarctic Aitken Basin.”
For further information, refer to the study published in the journal Nature.
_____
JC Andrews-Hanna et al. 2025. The southern impact excavated a magma ocean in the Moon’s South Pole Aitken Basin. Nature 646, 297-302; doi: 10.1038/s41586-025-09582-y
Enceladus, Saturn’s moon, constantly emits ice grains and gas plumes from its subterranean seas through fissures near the Antarctic region. A research team from the University of Stuttgart and the University of Berlin Fly utilized data from NASA’s Cassini spacecraft to chemically analyze newly emitted particles originating from Enceladus’ ocean. They successfully identified intermediates of organic molecules that may have biological significance (including aliphatic and (hetero)cyclic esters/alkenes, ethers/ethyl, and tentatively, nitrogen and oxygen-containing compounds), marking the first discovery of such compounds among ice particles in extraterrestrial oceans.
Artist’s impression of NASA’s Cassini spacecraft navigating through the plumes erupting from Enceladus’ Antarctic region. These plumes resemble geysers and release a mix of water vapor, ice grains, salt, methane, and various organic molecules. Image credit: NASA/JPL-Caltech.
Enceladus has a diameter of approximately 500 km, and its surface is covered by ice shells that are about 25-30 km thick on average.
Cassini made the first revelation of a hidden ocean beneath Enceladus’ surface back in 2005.
A current emerges from a fissure near the moon’s Antarctic, sending ice grains into space.
Some ice particles, smaller than grains of sand, settle on the moon’s surface, while others escape, forming a ring that orbits Enceladus around Saturn.
“Cassini consistently detected samples from Enceladus while passing through Saturn’s E ring,” noted Nozail Kawaja, a researcher at the Free University of Berlin and the lead author of the study.
“Many organic molecules have already been identified within these ice grains, including precursors to amino acids.”
The ice grains in the ring may be hundreds of years old and could have undergone changes due to strong cosmic radiation.
Scientists aimed to analyze the recently released grains to enhance their understanding of the dynamics within Enceladus’ seas.
Fortunately, they already had the relevant data. In 2008, Cassini flew directly through the ice sprays. The released primitive particles were emitted just minutes before they interacted with the spacecraft’s Cosmic Dust Analyzer (CDA) at speeds of approximately 18 km/sec. These represented not only the most recent ice grains Cassini has detected but also the fastest.
“Ice grains encompass not just frozen water, but also other molecules containing organic matter,” Dr. Kawaja stated.
“Lower impact speeds can break the ice, leading to signals from water molecule clusters that may obscure signals from certain organic molecules.”
“However, when ice grains strike the CDA at high speeds, the water molecules do not cluster, allowing previously hidden signals to emerge.”
Years of data from previous flybys were necessary to interpret this information.
This time, the authors successfully identified the molecules contained in the freshly released ice grains.
The analysis showed that certain organic molecules known to be present in the E rings were also found in the fresh ice grains, affirming their formation within Enceladus’ seas.
Furthermore, they discovered a completely new molecule that had never before been observed in Enceladus’ ice grains.
Chemical analyses revealed that the newly detected molecular fragments consisted of aliphatic, (hetero)cyclic esters/alkenes, ethers/ethyl, and potentially nitrogen and oxygen-containing compounds.
On Earth, these same compounds participate in a series of chemical reactions that ultimately yield more complex molecules essential for life.
“Numerous pathways from the organic molecules detected in Cassini’s data to potentially biologically relevant compounds exist, enhancing the possibility of habitability on the moon,” Dr. Kawaja mentioned.
“We have more data currently under review, so we anticipate further discoveries soon.”
“The molecules we identified in the newly released materials indicate that the complex organic molecules Cassini detected within Saturn’s E ring are not merely a result of prolonged exposure to space; they are readily found within Enceladus’ ocean,” added co-author Dr. Frank Postberg, also from the Free University of Berlin.
For more details, refer to the study featured in this month’s edition of Natural Astronomy.
____
N. Kawaja et al. Detection of organic compounds in newly released ice grains from the Enceladus ocean. Nat Astron Published online on October 1, 2025. doi: 10.1038/s41550-025-02655-y
Melting ice sheets in Antarctica will elevate sea levels
durktalsma/getty images
Recent studies suggest that Antarctica may have crossed a critical climate threshold, diminishing hope for recovery. Experts highlight a concerning correlation between the abrupt decline in sea ice since 2016 and anthropogenic ocean warming.
Historically, Antarctic sea ice levels remained stable despite rising global temperatures. However, a drastic shift occurred in 2016, marked by significant reductions in sea ice extent.
By February 2023, Antarctic Ocean Ice recorded a new all-time low, marking the third consecutive summer of reduced sea ice within just seven years. September 2023 also saw unprecedented high levels of Antarctic Ocean Ice.
While climate models have long forecasted reductions in Antarctic sea ice, the pace and scale of the decrease since 2016 are alarming. Researchers convened at the Royal Society in London to evaluate whether these changes signal a critical turning point.
As Marilyn Rafael from the University of California, Los Angeles, notes, natural climate variability alone cannot account for such a rapid shift.
Satellite observations of sea ice have been available since 1979. By utilizing proxy data from Antarctic weather stations, Raphael and her team extended their research timeline back to the early 20th century.
Their analysis, based entirely on historical data, indicates that the likelihood of reaching a minimum sea ice extent in 2023 was less than 0.1%. “We are observing extreme patterns in sea ice behavior,” she explained at the Royal Society Conference.
Alexander Hauman from the Alfred Wegener Institute in Germany emphasizes that this rapid decline in ice formation signifies a climate tipping point, with potential repercussions for the entire continent and broader climatic and ecological systems.
“The entire Antarctic sea ice system is reacting collectively,” he stated at the meeting, noting that the changes observed are poised to have long-term implications.
Last summer’s minimum Antarctic Ocean Ice extent was significantly below historical averages
NASA’s Scientific Visualization Studio
Hauman explains that “changes in ice dynamics” may be responsible for this phenomenon. Emerging research indicates that warming seawater contributes to accelerated ice loss, as roughly 90% of the excess heat generated by human activity is absorbed by the oceans.
In Antarctica, a layer of warm, fresh water separates colder, mixed surface waters from warm deep-sea water. However, a recent study by Hauman and his team highlights how shifts in wind patterns and salinity in the Southern Ocean have severely weakened this barrier since 2015, allowing warm deep water to rise to the surface and encourage ice melting. This phenomenon is further exacerbated by climate change-induced warming of deep waters, as indicated by recent research.
Hauman suggests that natural fluctuations in climate may have triggered modifications in salinity and wind patterns, intensifying the effects of anthropogenic warming trapped in deep waters. This could imply that the impact of warming seawater is already being felt in Antarctica, obstructing new sea ice formation.
Hauman notes that recent shifts in ocean circulation can only be counteracted by either mitigating upwelling effects or sudden alterations in salinity within the Southern Ocean. Nevertheless, the potential responses of the system remain highly uncertain.
The ramifications of these developments could be catastrophic. Antarctic sea ice plays a critical role in stabilizing land glaciers and ice sheets. Without adequate sea ice formation, the rate at which these ice structures melt may increase, leading to significant global sea level rise. It is estimated that the Antarctic ice sheet holds enough water to potentially raise global sea levels by up to 58 meters.
The depletion of ice in the Antarctic also alters the Earth’s surface albedo. Darker oceans absorb more solar heat compared to reflective white ice.
Additionally, vast stores of carbon trapped in the Southern Ocean could be released into the atmosphere as deep-sea temperatures rise, as suggested by various studies.
Researchers are just starting to grasp how these types of climate feedback mechanisms might unfold in Antarctica, after many years of relying on inaccurate and low-resolution models.
Marine biologists have identified three new species of deep-sea catanus fish belonging to the Lipalidae family in the Eastern Abyssian area of the Pacific (depths of 3,268-4,119 m).
In situ images of Careproctus colliculi in Monterey Bay, California, USA. Image credit: mbari.
The family of these fish, known as Repalidae, thrives in temperate to cold waters across the ocean basin.
These species play a significant role in ecosystems ranging from the intertidal zones to the hadal trenches (over 6,000 m).
They are well adapted to various habitats, likely due to their rapid evolutionary rates.
In shallower waters, these fish utilize specialized ventral suction discs to cling to rocks, adopting a curled, snail-like posture which gives rise to their common English name.
“The family Ripalidae comprises 31 accepted genera and 450 recognized species, with 43 being described in the last decade,” stated Dr. Mackenzie Gellinger from the State University of New York.
“At the family level, these fish are distinguished by their skate-like body, ventral suction discs formed by modified pelvic fins in many genera, and their elongated body structure.”
“Given the ecological significance of this family, the rapid discovery of new snail fish, and the important efforts needed to revise catanus classification, studying snail taxonomy is essential for advancing our understanding of marine biodiversity.”
The three new species are the bumpy snail (Careproctus colliculi), the dark snail (Careproctus yanceyi), and the sophisticated snail (Paralyparis em).
Paralyparis em and Careproctus yanceyi were collected using a suction sampler from a depth of 4,100 m via the human occupied vehicle (HOV) Albin on the R/V Atlantis.
Careproctus colliculi was gathered by remotely operated vehicles (ROVs) Doc Ricketts on the R/V Western Flyer using a suction sampler from under 100 km off the coast of Monterey Bay, California.
To describe these new species, the authors utilized microscopy, micro-computed tomography (Micro-CT) scans, and meticulous measurements to gather specific data on size, shape, and various physical characteristics such as fin rays and vertebrae for each fish.
“Careproctus colliculi is identified by its pink body, 22 cerebral rock rays, rounded head, eight caudal rays, large eyes, and well-formed wing-like structure that creates a large suction disc,” they explained.
“Careproctus yanceyi features a medium-sized abdominal suction disc, a single nostril, and six branched rays, distinguishing it from other Eastern Pacific deep-sea snails, which have round heads and entirely black bodies with horizontal mouths.”
“Paralyparis em is marked by its long, black, laterally compressed body, absence of a suction disc, sharply angled jaw, a single chest radial, anteriorly positioned anal fin, and five branched rays.”
Researchers also sequenced the DNA of the fish and compared it with other snail species to contextualize the new species within their evolutionary framework.
“Taxonomic methods are crucial for comprehending the organisms we share our planet with and for studying and safeguarding global biodiversity,” Dr. Gellinger asserted.
“The deep sea is home to an astonishing variety of creatures with remarkable adaptations.”
“These three catanus fish serve as a reminder of how much remains unknown about life, the thrill of curiosity, and the power of exploration on Earth.”
The research findings are detailed in a new paper published in the journal Ichthyology and Herpetology.
____
Mackenzie E. Gellinger et al. 2025. Description of three newly discovered Abyssal snails (Liparidae) from the Eastern Pacific Ocean. Ichthyology and Herpetology 113(3): 487-506; doi: 10.1643/i2024069
New structural faults have been discovered beneath the Atlantic Ocean, potentially heightening the risk of significant earthquakes and tsunamis that could impact the region. This finding is based on a recent study published this week in Natural Earth Science.
For centuries, the reason behind Portugal’s susceptibility to major earthquakes, despite its distance from prominent fault lines, has puzzled scientists.
On November 1, 1755, Lisbon was struck by a catastrophic earthquake registering 8.7 on the Richter scale, resulting in the deaths of tens of thousands and triggering a tsunami that reached the Caribbean. In 1969, a magnitude 7.8 tremor off the Portuguese coast killed 25 individuals.
“One of the challenges is that these earthquakes occur on completely flat plains and are distant from fault lines,” stated Professor Joan Duarte, a geologist at the University of Lisbon and the study’s lead author, as reported in BBC Science Focus.
“Following the 1969 earthquake, it became clear that there were signs of a subduction belt, indicating something unusual in that region.”
The subduction zone, where one tectonic plate moves under another, is responsible for some of the planet’s most destructive “megathrust” earthquakes, including the catastrophic events in the Indian Ocean in 2004 and Tohoku in 2011. However, the Atlantic Ocean has traditionally been viewed as relatively stable, with its plates slowly drifting along the mid-Atlantic ridge.
Duarte’s team compiled earthquake records and utilized computer models from the Horseshoe Abyss Monkey Plain, a deep seabed located southwest of Portugal. They uncovered evidence that the mantle—a hot, dense layer beneath the Earth’s crust—is undergoing a process known as peeling.
“The base of the plate is separating as if peeling off, like the sole of a shoe,” Duarte explained. “The first moment of realization came when I thought, ‘Oh, there’s something out there.’ The second was when our computer models confirmed this peeling process.”
This artwork illustrates the 1755 Lisbon earthquake. A combination of earthquakes, tsunamis, and subsequent fires nearly obliterated the Portuguese capital – Credit: Getty
This phenomenon is unusual in oceanic crust, which typically behaves like a “crème brûlée,” resting on a more pliable layer below due to its rigid buoyancy.
In this instance, it appears that water has been infiltrating the rock for millions of years, chemically weakening it and enabling the mantle mass to descend toward the Earth’s depths.
The research suggests that we might be witnessing the emergence of a new subduction zone in the Atlantic Ocean, which could ultimately reunite Africa, Europe, and the Americas into future supercontinents.
For now, however, the immediate concern is the potential for earthquakes.
“A significant earthquake will occur again,” Duarte emphasized.
“If there’s a forecast for rain tomorrow, you’d take an umbrella,” he added. “We don’t need to know the exact time of the rain, just that we must be prepared.”
“The same goes for earthquakes. While we can’t predict when major ones will strike, we understand the likelihood, so we need to be ready.”
Read more:
About our experts
Joan Duarte is an assistant professor of tectonics at the University of Lisbon and serves as the president of the Department of Tectonics and Structural Geology within the European Union of Geosciences. His research has been featured in journals such as Geophysical Research Letters, Nature Communications, and Geology.
Approximately 390 million years ago during the Devonian period, marine life began to explore previously unoccupied depths. A recent study, conducted by researchers from Duke University, Washington University, NASA’s Virtual Planetary Research Institute, and Caltech, reveals that this underwater migration was spurred by a lasting increase in deep-sea oxygen levels, linked to the ground diffusion of woody plants. This rise in oxygen coincided with a time of notable diversification among jawed fish.
Artistic rendering of Brindabellaspis stensioi (foreground) alongside various other Devonian fossil fish. The white shark and human divers in the upper right corner symbolize modern jaw vertebrates. Image credits: Hongyu Yang/Qiuyang Zheng.
“While oxygen is recognized as essential for animal evolution, establishing its role in trends of animal diversification can be challenging,” remarks Dr. Michael Kipp, a researcher at Duke University.
“This study strongly supports the idea that oxygen has influenced the timing of early animal evolution, particularly concerning the emergence of jawed vertebrates in deep-sea environments.”
For years, scientists believed that deep-sea oxygenation was a singular event that occurred at the onset of the Paleozoic era, around 540 million years ago.
However, recent findings suggest that oxygenation takes place in stages, first making coastal regions more hospitable for respiratory organisms, followed by deeper waters.
Dr. Kipp and his team investigated the timing of these stages by examining sedimentary rocks formed beneath deep seawater.
They focused on selenium within the rocks, an element utilized to ascertain whether oxygen levels were high enough to support life in the ancient ocean.
In marine settings, selenium exists in various forms known as isotopes, which differ based on weight.
At oxygen levels conducive to animal life, the ratio of heavy to light selenium isotopes shows significant variation.
Conversely, at oxygen levels too low for most animals, the ratios remain relatively stable.
By analyzing selenium isotope ratios in marine sediments, researchers can deduce whether oxygen levels were adequate to sustain aquatic life.
The team collected 97 rock samples from around the globe, dating from 252 to 541 million years ago.
These samples were sourced from locations across five continents that were once situated along continental shelves millions of years ago, where the continental edge meets a steep drop-off underwater.
After processing the rocks through grinding, melting, and purifying selenium, the team examined the selenium isotope ratios in each sample.
Their findings reveal that two significant oxygenation events took place in deeper waters of the outer continental shelf, starting during the Mid Devonian, around 540 million years ago, and again between 393 and 382 million years ago during the Paleozoic’s Cambrian period.
For extended periods, oxygen levels plummeted, making survival challenging for most marine life.
“Our selenium data indicates that the second oxygenation event was permanent,” stated Kunmanee ‘Mac’ Bubphamanee, PhD candidate at the University of Washington.
“This event initiated in the mid-Devonian period and has persisted in our younger rock samples.”
This oxygenation event coincided with significant changes in ocean evolution and ecosystems, often referred to as the Paleozoic marine revolution.
Fossil evidence indicates that oxygen became a stable presence in deeper waters, allowing jawed fish known as Gnathostomes to invade and diversify in these environments.
These organisms grew larger, likely due to the supportive oxygen levels facilitating their growth.
The Devonian oxygenation event also correlated with the proliferation of woody plants.
“Our hypothesis posits that the increase in woody plants released more oxygen into the atmosphere, thereby elevating oxygen levels in deeper marine environments,” Dr. Kipp stated.
The cause behind the initial temporary oxygenation event during the Cambrian period remains more obscure.
“What is evident is that the subsequent drop in oxygen post-initial event constrained the spread and diversification of marine animals into deeper continental shelf environments,” Dr. Kipp explained.
“Today, marine oxygen levels are balanced with those in the atmosphere.”
“However, in specific zones, marine oxygen can plummet to undetectable levels.”
“Some of these areas arise from natural phenomena.”
“Still, they are frequently exacerbated by nutrient runoff from fertilizers, industrial activities that degrade plankton, and subsequent oxygen depletion as it decomposes.”
“This research clearly outlines the relationship between oxygen and marine life.”
“It’s a balance established around 400 million years ago, and it would be regrettable to disrupt it in the years to come.”
This study is set to be published this week in Proceedings of the National Academy of Sciences.
____
Kunmanee Bubphamanee et al. 2025. Marine oxygenation in Mid Devonian allowed the expansion of animals into deeper water habitats. PNAS 122 (35): E2501342122; doi: 10.1073/pnas.2501342122
IE 11 is not supported. For an optimal experience, please visit a different browser.
SpaceX Launch Postponed Due to Weather
04:08
Currently Streaming
The “Prosperity” Ecosystem Discovered 30,000 Feet Below Pacific Ocean
00:48
Up Next
New Report Reveals Rising Costs Due to Weather Disasters
02:29
Fossilized Dinosaur Found Under Denver Museum’s Parking Lot
01:46
Exploring Why July 9, 2025, Is One of the Shortest Days in History
03:10
EPA Proposes to Lift Greenhouse Gas Restrictions on Power Plants
03:16
Kate the Chemist Shares Fun Science Experiments for Summer Boredom
04:34
Shark Bites Surfer’s Board, Leading to Beach Closures in California
03:08
Climbers Ascend Everest Using Controversial Xenon Gas
03:46
Australian Mother Considers “Cryogenic” Option After Untimely Loss
06:45
Underwater Volcanoes Near the Pacific Coast Erupting at Alarming Speed
02:07
Watch the Blue Origin Crew Experience Zero Gravity Upon Capsule Entry
00:49
Gayle King Not Afraid to Experience Spaceflight Risks
04:18
All-Female Crew Returns from Blue Origin Space Mission: “We Went to Space!”
01:58
Hospital Provides Second Chances for Sea Turtles
04:11
Biotech Companies Claim 13,000-Year-Extinct Wolf Has Returned
02:43
Video Shows Genetically Modified Wolf, Claims Biotech Company
00:46
Carbon-Absorbing Crops Help Offset Air Pollution
02:59
Harvard Professors Use AI to Create Digital Twins for Tutoring Experiments
03:15
SpaceX Launches FRAM2 Missions to Earth’s Poles
01:45
Researchers have identified flourishing ecosystems of clams, tubeworms, and other species more than 30,000 feet deep in the Pacific Ocean. According to findings published in the Nature Journal, these represent “the deepest and most extensive chemical synthesis-based communities recognized.” July 31, 2025
SpaceX Launch Postponed Due to Weather
04:08
Currently Streaming
Discovery of the “Prosperity” Ecosystem Deep Below the Pacific Ocean
00:48
Up Next
Report Reveals Rising Costs of Weather-Related Disasters
02:29
Fossilized Dinosaur Unearthed Beneath Denver Museum’s Parking Lot
01:46
Understanding the Shortest Recorded Day: July 9, 2025
03:10
EPA’s New Goals: Removing Greenhouse Gas Restrictions in Power Facilities
Warming oceans might elevate storm intensity, exemplified by Hurricane Milton in 2024
NOAA
Scientists have cautioned that the extreme ocean temperatures observed since 2023 could indicate the onset of drastic changes in global marine conditions, posing a severe risk to life on our planet.
Historic ocean heat waves unfolded in the North Atlantic and Pacific in 2023, marked by their unprecedented severity, duration, and geographical spread, many persisting for over a year.
These heat waves have led to record-high sea surface temperatures globally in 2023 and 2024, contributing to severe weather patterns on land and resulting in back-to-back years being declared the hottest on record.
“While there’s been a gradual increase in ocean temperatures over the past 40-50 years, 2023 stands out as a pivotal year, with significant ocean heat waves impacting numerous regions,” stated Matthew England from the University of New South Wales, Australia.
Sea surface temperatures worldwide remain at alarming heights, with the Mediterranean currently experiencing marine heat waves, as water temperatures exceed 5°C (9°F) during this time.
Researchers are concerned that the oceans may be shifting to new, hotter states, endangering their predictions for both short-term weather phenomena like hurricanes and long-term climate change trends.
To understand the situation, Zhenzhong Zeng from China’s Southern University of Science and Technology is collaborating with colleagues to pinpoint the causes of the 2023 global ocean heat wave by analyzing heat movement within the ocean, wind patterns, and ocean currents. They found that reduced cloud cover significantly increases solar radiation reaching the water, compounded by weak winds and the influence of the warming El Niño pattern in the Pacific Ocean.
Considering the heat wave that began in earnest in 2023 and continues in various regions, Zeng suggests this could be the start of a “new normal” for the world’s oceans. He notes that new data reveals an exponential rise in ocean heat, contradicting previous climate model forecasts.
Persistently elevated water temperatures severely impact marine ecosystems, heightening the risk of coral reef collapse, causing mass die-offs, and leading to shifts in marine species distributions. This also exacerbates heating on land, resulting in intensified droughts, heatwaves, wildfires, and storms.
Zeng expressed that he is “very alarmed” by this potential sea regime change, adding, “I believe nearly all predictions made by Earth System models are incorrect.”
Conversely, some experts argue that it may be premature to declare fundamental shifts in ocean dynamics. Neil Holbrook from the University of Tasmania in Australia points out that there is currently no “clear evidence” to indicate we have reached a critical turning point, given the limited years of data to assess. “I cannot predict what will happen next year; [ocean temperatures] could return to more typical patterns,” he remarked.
However, Holbrook stressed that without substantial reductions in greenhouse gas emissions, “marine heat waves will likely continue to gain intensity and duration, potentially escalating faster than various marine species can adapt.”
A lifeline has been extended to the residents of Tuvalu, a low-lying Pacific nation grappling with the impacts of rising sea levels. Each year, Australia permits 280 Tuvaluan individuals to reside there. This agreement anticipates a relocation of the entire population within the next few decades.
The Australian Tuvalu Farapili Union, regarded as the world’s first climate migration agreement, also allocates funds for adaptation to aid those who are lagging behind.
Could this serve as a prototype for managing climate migration gracefully before calamities ensue? However, the situation is far from ideal. In order to secure this deal, Tuvalu had to concede to Australia having a voice in future security and defense matters. Few nations may find such terms acceptable.
Moreover, Tuvalu’s population is minuscule. In a country like Australia, which has 28 million residents, accepting around 10,000 climate migrants is relatively insignificant. It’s estimated that between 25 million and 1 billion people could face forced displacement by 2050 due to climate change and other environmental pressures. Where will they go?
Environmental factors could force 1 billion people to move by 2050
Many assert that wealthy nations, historically the largest emitters of carbon dioxide contributing to global warming, have a moral duty to assist those affected by climate change. However, discussions on these matters have yet to translate into the legal recognition or acceptance of forced climate migration. In fact, many high-income nations seem increasingly resistant to various forms of immigration.
There have been some progressions in creating funds for “loss and damage” to aid affected countries dealing with the aftermath of global warming. This could potentially curtail the necessity for future climate migration, yet the promised financial support to date is only a fraction of what is essential.
The foremost action that any nation should undertake is to limit future warming through emission reductions, but global emissions continue to rise. Regrettably, the Farapili Union symbolizes a decline into the ocean, not a turnaround.
Recent Summers Show Antarctic Sea Ice Cover at Unprecedented Lows
Nature Picture Library / Alamy
The decline of sea ice around Antarctica has led to a doubling of icebergs calved from the ice sheet and increased spikes in seawater temperatures, exacerbating the effects of heat accumulation in the Southern Ocean.
In recent years, sea ice extent at both poles has sharply decreased. In 2023, the Antarctic winter sea ice area fell 1.55 million square kilometers short of the expected average.
This loss is equivalent to disappearing an ice area nearly 6.5 times larger than the UK. Projections for 2024 suggest similarly low figures, with 2025 also anticipated to experience harsh conditions.
Edward Dodridge from the University of Tasmania and his team are investigating the implications of the long-term reduction of protective buffers provided by Antarctic sea ice.
The researchers discovered that the average temperature in the South Seas has increased by 0.3°C between latitudes 65° and 80° since 2016. Additionally, summer sea ice losses have similarly raised temperatures by 0.3°C.
Alarmingly, the heat from a year with particularly low sea ice does not dissipate by the next year. Instead, it continues to warm the ocean for at least the following three years, resulting in even greater temperature increases than expected, according to Dodridge.
“For some time, we’ve known that summer sea ice loss contributes to ocean warming because ice and its reflective snow cover keep heat at bay,” explains Doddridge.
“The fact that the ocean retains warming effects for three years complicates the consequences of warming in the Southern Ocean.”
Moreover, the dramatic reduction in sea ice may accelerate the loss of inland ice sheets. When sea ice freezes, it dampens the expansion of the South Seas, preventing contact with the ice sheets sitting above Antarctica. Once the protective sea ice barrier disappears, the coastal ice sheets become more susceptible to breaking apart.
The research found that for every additional 100,000 square kilometers of sea ice lost, six more icebergs larger than one square kilometer were formed. “We witnessed double the amount of icebergs at periods of low sea ice,” said Doddridge.
Additionally, the reduction in sea ice significantly impacts species that rely on transferring from the ocean to solid ground for survival. The study indicates that species like the Emperor Penguin (Aptenodytes forsteri) and Crabeater Seal (Lobodon carcinophagus) may face severe challenges.
The scientific investigation in Antarctica is becoming increasingly difficult as the presence of sea ice is crucial for safely resupplying research stations.
Nellie Abram from The Australian National University remarks that “this analysis shows very few positives surrounding the loss of sea ice and its impact on the environment.”
“In years with extremely low sea ice, the Antarctic ecosystem continues to experience effects for years afterward. This isn’t just a one-time event,” Abram asserts. “There are numerous ways this loss of ocean ice influences Antarctic ecosystems.”
Strategies to uphold the current involve oversized versions of parachute-like ocean anchors
Ed Darnen (2.0 by CC)
As part of an ambitious initiative to avert severe climate change, large parachutes could be deployed into Atlantic waters using transport tankers, drones, and fishing vessels.
The Atlantic Meridional Overturning Circulation (AMOC) moves warm water from the tropics northward and helps stabilize temperatures in Northern Europe.
Nevertheless, the swift melting of Arctic ice and rising sea temperatures have hampered these currents, prompting some scientists to warn that they could falter entirely within this century. Such an event would disrupt marine ecosystems and exacerbate the cooling of the European climate.
Experts emphasize the urgent need to cut greenhouse gas emissions to mitigate the risk of AMOC collapse and other catastrophic climate “tipping points.” However, some are exploring alternative, more fundamental methods to preserve the current.
Stuart Haszeldine from the University of Edinburgh, along with David Sevier, introduced a concept from the British water treatment firm Strengite during a recent meeting in Cambridge, UK. They propose utilizing just 35 ocean tugs, each capable of pulling underwater parachutes roughly half the size of a soccer pitch, which could effectively move enough water to maintain the current. “A modest amount of energy and equipment can yield a significant impact,” Haszeldine remarks.
These parachutes, designed similarly to existing ocean anchors, stabilize containers in rough weather while also aiding in water movement across the sea surface. Each parachute features a central hole 12 meters wide to allow marine creatures to escape.
The operation would run 365 days a year in a rotating schedule, using drones, transport tankers, tugs, or wind kits. “It’s a small but consistent intervention,” notes Haszeldine.
Sevier refers to this proposal as “any Mary,” indicating a solution to stave off the severe consequences of AMOC collapse. “This is about buying time,” he asserts, emphasizing the need for the world to reduce emissions sufficiently to stabilize global temperatures at safe levels.
However, leading AMOC researchers express skepticism about the idea. Rene van Westen from the University of Utrecht, Netherlands, highlights that the density differences between cold, salty water and warm, fresh water play a crucial role in the descent and upwelling movements that sustain AMOC.
“If this idea is to work,” Van Westen argues, “you can only use surface wind to influence the top layer of water.
Stephen Rahmstoef from the Potsdam Institute for Climate Impact Research concurs. “The challenge lies not in moving surface water horizontally but in sinking it to depths of 2,000 to 3,000 meters and returning it south as a cold, deep current,” he states.
Meric Srokosz of the UK National Oceanography Centre believes the proposal is “unlikely to succeed,” given the variable weather conditions that complicate equipment deployment in the oceans.
Haszeldine welcomes feedback from fellow scientists regarding the proposal and hopes it will inspire ocean and climate modelers to assess the ecological and environmental ramifications of the plan. “I believe this warrants further investigation,” he asserts.
More generally, Haszeldine argues for increased research focused on climate intervention strategies to sustain ocean circulation: “I don’t see anyone else working on ocean currents.”
Certainly! Here’s the rewritten content while maintaining the HTML tags:
Satellite perspective of coral reefs in New Caledonia
ShutterStock/Best-Backgrounds
The decline of coral reefs might come with unexpected advantages. Research suggests that this deterioration allows the oceans to absorb up to 5% more carbon dioxide by 2100, which may decelerate the buildup of this greenhouse gas in the atmosphere.
“If your primary concern is the CO2 concentration in the atmosphere, this could be viewed as a beneficial effect,” states Lester Kwiatkowski from Sorbonne University in Paris, France. However, he cautions that the loss of coral also leads to diminished biodiversity, jeopardizes fisheries, and heightens the vulnerability of coastal regions to rising sea levels.
The extent of global warming is heavily influenced by atmospheric CO2 levels. To date, land and oceans have collectively absorbed around half of the surplus CO2 we’ve emitted. Thus, elements that affect these so-called land or marine carbon sinks can significantly influence future climate scenarios.
Corals are often believed to sequester CO2 from seawater while they develop their calcium carbonate structures. In reality, this process—known as calcification—actually releases CO2 as a net byproduct.
“Corals typically take in inorganic carbon from the ocean in forms like carbonate and bicarbonate ions, converting them into calcium carbonate, which results in CO2 being expelled back into seawater.”
This suggests that if the growth of coral reefs slows or halts, there will be a reduction in CO2 emissions from these reefs, thereby allowing the ocean to absorb more of this greenhouse gas from the atmosphere—a factor currently absent from climate models.
Current studies indicate that coral reef calcification has already declined due to rising ocean temperatures, leading to extensive coral bleaching. Additionally, increased CO2 levels have caused ocean acidification, which complicates the formation of carbonate structures and can even trigger dissolution.
Kwiatkowski and his research team have published estimates detailing how corals are susceptible to warming and ocean acidification. They utilized computer models to project how these changes could affect marine carbon sinks under various emission scenarios. Their findings indicate that by 2100, the ocean may sequester an additional 1-5% more carbon, which could escalate to up to 13% by 2300.
This prediction may be conservative, as Kwiatkowski notes it overlooks additional factors contributing to coral reef degradation, such as overfishing and the spread of coral diseases.
Conversely, the research assumes that corals lack the capacity to adapt or acclimate. Chris Ju judge from the University of Hawaii at Manoa, who was not part of this study, remarks on this perspective.
“If we encounter the worst-case or medium-case outcomes outlined in this study, it portends significant destruction of coral reefs globally,” says Ju judge. “I believe the authors could arrive at different conclusions by considering potential adaptability in corals and other reef organisms under moderate levels of climate change.”
If Kwiatkowski’s team’s projections hold true, the amount of CO2 that leads to a certain degree of warming—the so-called carbon budget—may actually be larger than current estimates.
“Even if we’re facing dire outcomes, it’s critical to refine our understanding of the carbon budget to ensure its accuracy,” asserts Kwiatkowski.
Topic:
Feel free to let me know if any further adjustments are needed!
Research has shown that various orange-striped fish shrink during heat waves off the coast of Papua New Guinea. These smaller fish are more likely to survive.
Climate change is causing heat waves to become more frequent and severe underwater. Elevated water temperatures can lead to the bleaching of the sea anemones that clownfish rely on, prompting them to adapt in order to survive.
During the severe heat wave of 2023, scientists tracked 134 colorful clownfish in Kimbe Bay, discovering that 101 of them exhibited significant reductions in length due to heat stress.
“We were genuinely surprised at first when we observed them shrinking completely,” remarked Morgan Bennett Smith, a research author at Boston University. The findings were published on Wednesday in the Journal of Science Advances.
Two clowns next to an anemone in Kimbe Bay off the coast of Papua New Guinea. Morgan Bennett Smith / AP
Researchers are still unsure about how clownfish shrink, but one theory suggests they may be reabsorbing their own bone material. Smaller fish need less food, allowing Kakulfish to conserve energy during stressful conditions by becoming smaller.
Certain clownfish breeding pairs also exhibited synchronized contractions that improved their survival. The females maintained the social hierarchy and adjusted their size to remain larger than their partners, according to the researchers.
Additionally, other species are also shrinking in response to heat. For instance, marine iguanas reduce in size during El Niño events, which warm waters in the Galapagos. However, this coping mechanism has not been reported in reef fish until now.
“This is an additional strategy that fish employ to adapt to a changing environment,” said Simon Thorold, a marine ecologist at the Woods Hole Marine Facility who was not part of the research.
A kakuru fish next to anemone in Kimbe Bay off the coast of Papua New Guinea. Morgan Bennett Smith / AP
This strategy may help fish withstand heat waves in the short term, but it remains uncertain how they will cope if such conditions persist over the coming years, Thorold noted.
The researchers found that these reductions in size were temporary. Clownfish were able to “catch up” and grow again once the environment became less stressful.
“These natural systems are severely stressed, but they exhibit remarkable resilience,” Versteeg states.
This website uses cookies so that we can provide you with the best user experience possible. Cookie information is stored in your browser and performs functions such as recognising you when you return to our website and helping our team to understand which sections of the website you find most interesting and useful.
Strictly Necessary Cookies
Strictly Necessary Cookie should be enabled at all times so that we can save your preferences for cookie settings.
