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Breakthrough Model Reveals How Nutrients Might Access Europa’s Icy Shell to Nourish Its Hidden Ocean

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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.

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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

Source: www.sci.news

Evidence Suggests Mars Once Had an Ocean Comparable to the Arctic Ocean

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Mars Was Once Much Wetter

NASA/USGS

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.”

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Historic High Seas Treaty Now in Effect: First-Ever Protection for Ocean Waters

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Antarctic Trawler

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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.”

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Source: www.newscientist.com

Sinking Arctic Ocean Trees: A Natural Solution to Removing 1 Billion Tons of CO2

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Trees Floating Towards the Arctic Ocean

Trees Floating Towards the Arctic Ocean

Carl Christoph Stadie/Alfred Wegener Institute

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.

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New Modeling Study Reveals Surprisingly Calm Ocean Floor on Europa

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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.

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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

Source: www.sci.news

How Europa’s Thick Ice May Obstruct the Hunt for Ocean Life

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Europa’s Ice: A Thick Shell Over a Salty Ocean

Claudio Caridi / Alamy

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.

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New Research Discovers Titan Lacks an Underground Ocean

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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.

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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

Source: www.sci.news

Climate Change is Impacting the Deepest Reaches of the Arctic Ocean

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Deep Waters of the Arctic Ocean Are Warming

Mozgova/Shutterstock

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.

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Source: www.newscientist.com

Accelerated Melting in Antarctica May Support Key Ocean Currents

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Impact of Melting Antarctic Ice on Ocean Currents

Juan Barretto/AFP via Getty Images

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.

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Source: www.newscientist.com

Enceladus’ Ocean Could Support Life More Effectively Than We Realize

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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.

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Southern Impact Reveals Magma Ocean in Moon’s Largest Crater: Study

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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

Source: www.sci.news

Cassini Discovers Organic Molecules in Newly Released Ice Grains from Enceladus’ Ocean

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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

Source: www.sci.news

Antarctica Could Have Crossed a Critical Ocean Tipping Point

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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.

Topics:

  • Climate change/
  • Antarctica

Source: www.newscientist.com

Three Newly Discovered Species of Abyssinian Snail in the Pacific Ocean

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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

Source: www.sci.news

A Potential New Mega-Earthquake Hotspot Could Emerge Under the Atlantic Ocean

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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.

Source: www.sciencefocus.com

Mid-Debonian Ocean Oxygenation Enables Deeper Habitat Expansion for Marine Life

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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

Source: www.sci.news

Ecosystem Unearthed 30,000 Feet Beneath the Pacific Ocean

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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

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Source: www.nbcnews.com

Unprecedented Ocean Heat Waves Could Signal Lasting Changes in Our Seas

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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.”

Topics:

Source: www.newscientist.com

Australia’s Tubal Climate Movement Treaty: A Step Back for Ocean Health

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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.

Topic:

  • Climate change/
  • Global warming

Source: www.newscientist.com

Antarctic Ocean Ice Loss Accelerates Ocean Warming Beyond Predictions

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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.”

Topics:

  • Climate Change/
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Source: www.newscientist.com

AMOC: An Ambitious Strategy to Preserve Vital Ocean Currents Using Giant Parachutes

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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.”

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Source: www.newscientist.com

The Warming Ocean: Uncovering Unexpected Benefits from Coral Reef Loss

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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.

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Source: www.newscientist.com

Clownfish Will Endure and Adapt to Rising Ocean Temperatures

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To endure Rising ocean temperatures, clownfish adapt by decreasing their size.

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.

Source: www.nbcnews.com

First verified photo of a colossal squid in the ocean depths

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First confirmed live observation of a giant squid

ROV Subastian/Schmidt Ocean Institute

The giant squid, the planet’s largest invertebrate, was first photographed alive in its wild habitat.

For decades, giant squids like Kraken (Mesonychoteuthis hamiltoni) It was more myth than reality. Scientists only had a vague sense of its appearance from fragments of remains found in the stomachs of whales eating molluscs. In fact, it was those ruins that the species was officially described by zoologists in 1925.

Finally, in 1981, Antarctic fishermen happened to play a giant squid that lived in a fishing net. Since then, animals have been killed or washed sometimes as fishing baikatches or died on land.

Containers from last month Schmidt Ocean InstituteThe US-based nonprofit was investigating the South Sea near the South Sandwich Islands and was streaming footage from a remotely controlled deep-sea camera when online viewers flagged it that they might have just shot a giant squid.

Based on the hints, the researchers sent high-resolution footage to independent squid experts. Experts have confirmed that online viewers’ predictions are correct. The squid had a distinctive hook along the sucker on its eight arms, a characteristic of a giant squid. I was roaming 600 meters below the surface.

The giant squid is thought to grow up to 7 meters long and weigh up to 500 kilograms, but the squid caught between the camera was 30 cm long: baby.

“Every time you descend into the deep water, it’s amazing to find something new and exciting,” he says. Jyotika Virmani of the Schmidt Ocean Institute.

Giant squid It may have already been filmed Natural habitat for 2023, by researchers from another US-based nonprofit organization. Corosal – However, the quality of the footage was too low, so no sightings were confirmed. A new squid recording may suggest that the 2023 footage actually captures a giant squid. “In the southern oceans, they have the same size, the same color, and the same depth.” Matt Murennan At Kolossal, we are still waiting for more confirmation.

However, there are no footage of huge squids of adults in the wild yet, and the lives of these giant invertebrates are still mystical, says Steve O’Sheapreviously at Auckland Institute of Technology in New Zealand, he created the name “Colossal squid” in the early 2000s. He once touted the animals as “serious inhabitants of the deep sea,” but now he is convinced that “like a giant gelatinous mites, it envelops a column of water near the ocean floor.”

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Source: www.newscientist.com

Researchers find that melting ice sheets are causing a reduction in the speed of the world’s strongest ocean currents

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Antarctic Circulating Current (ACC), which is more than four times as strong as the Gulf Stream, is the world’s strongest ocean current and plays an unbalanced role in the climate system due to its role as a major basin conduit. Scientists at the University of Melbourne and the Research Centre in Nordic Norway have shown that ACC will slow by about 20% by 2050 in high carbon emission scenarios. This influx of freshwater into the southern ocean is expected to alter the properties such as the density (salinity) of the ocean and its circulation patterns.

Sohail et al. High-resolution ocean and sea ice simulations of ocean currents, heat transport, and other factors were analyzed to diagnose the effects of temperature changes, saltiness, and wind conditions. Image credit: Sohail et al. , doi: 10.1088/1748-9326/adb31c.

“The oceans are extremely complex, finely balanced,” says Dr. Bishakhdatta Gayen, liquid mechanic at the University of Melbourne.

“If this current ‘engine’ collapses, serious consequences, including more climate change, including extreme extreme climate variability in certain regions, will accelerate global warming due to a decline in the ability of the ocean to function as a carbon sink. “

The ACC acts as a barrier to invasive species, like the southern burkelp and marine vectors such as shrimp and mollusks, which travel in the current from other continents reaching Antarctica.

If this current slows and weakens, it is more likely that such species will head towards the fragile Antarctica, potentially serious effects on food webs, which could change the available diet of Antarctic penguins, for example.

The ACC is an important part of the marine conveyor belt around the world, moving water around the world and linking the Atlantic, Pacific and Indian seas. These are the main mechanisms of exchange of heat, carbon dioxide, chemicals and biology throughout these basins.

In their study, the authors used Gadi, the fastest supercomputer in Australia located on the Access National Research Infrastructure.

They discovered that transport of seawater from the surface to the deepest could also be slower in the future.

“If ice melting accelerates as predicted by other studies, slowdowns are predicted to be similar in low emission scenarios,” Dr. Sohail said.

“The 2015 Paris Agreement aims to limit global warming to 1.5 degrees Celsius above pre-industrial levels.”

“Many scientists agree that we have already reached this 1.5 degree target, which could have an impact on the melting of Antarctic ice, making it even hotter.”

“Cooperative efforts to limit global warming (by reducing carbon emissions) will limit the melting of Antarctic ice and avoid the expected slowdown in ACC.”

This study reveals that the effects of ice melting and ocean warming on ACC are more complicated than previously thought.

“The melted ice sheets throw a large amount of fresh water from salt water into the salty sea.”

“This sudden change in ocean salinity has a series of results, including weakening of subsidence to the depths of surface seawater (called Antarctic bottom water), and based on this study, it includes weakening of the powerful marine jets surrounding Antarctica,” Dr. Gayen said.

study Published in the journal Environmental Survey Letter.

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Taimoor Sohail et al. 2025. Decreasing the polar current in the Antarctic due to polarization. environment. res. Rent 20, 034046; doi:10.1088/1748-9326/adb31c

Source: www.sci.news

AMOC: Crucial ocean currents are unlikely to shut down completely by the end of the century

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AMOC brings warm water north from the tropical region near the surface and takes cold water in opposite directions of the deep sea

noaa

Important ocean currents will rarely close by the end of this century, according to new findings that undermine the end of the impending catastrophic collapse.

The Atlantic Meridian Surrounding Circulation (AMOC) transports warm water from the tropical north and helps maintain temperatures in Northern Europe. The temperature and the influx of cold water from the Arctic ice weakens the current temperature, and scientists fear it can stop it completely. This will disrupt marine ecosystems and cool the European climate a few degrees faster.

Some researchers say that the irreversible closure of AMOC could be in the century. But I say this worst-case scenario is unlikely Jonathan Baker At the Met Office in the UK.

To investigate whether a complete AMOC collapse of this century is possible, Baker and his colleagues used 34 climate models to simulate changes in AMOC under extreme climate change, and greenhouse gas levels trained overnight from today's levels. The team also modeled a large amount of freshwater entering the North Atlantic at many times the rate of ice melting now.

They found that although AMOC is significantly weakened in these two scenarios, ocean currents continue in their weakened state, supported by deep-sea upwellings in the North Atlantic, driven by southern sea winds. “The Southern Ocean winds continue to blow, and this brings deep waters up to the surface. This works like a powerful pump,” Baker says. “This keeps AMOC running on models of this century.”

This finding helps explain why climate models generally simulate more stable AMOCs in the warming world compared to studies that rely on statistical methods. This tends to suggest that AMOC is more vulnerable.

Niklas Bore The Potsdam Climate Impact Institute in Germany said the findings are “good news” for those worried about the imminent collapse of the AMOC. “I agree that all cutting-edge climate models will not show a complete AMOC collapse within the 21st century.

However, the model does not predict a complete collapse of AMOC, but shows that quaternary reddish CO2 concentrations lead to a 20-81% reduction in the current intensity.

With AMOC weaker by about 50%, the impact on climate will become important, Baker says it will be important due to marine ecosystem disruption, sea level rise on the North Atlantic coastline, and changes in global rainfall patterns that affect crop harvests around the world. However, this type of weakening does not bring rapid cooling to Europe, he says.

In comparison, Bohr emphasizes that AMOC, which is 80% less than today, will have a devastating effect. “Of course, it's a nearly blocked AMOC,” he says. “It has all the impact on Europe's cooling and changing patterns of tropical monsoon, and all the things we are concerned about.”

Stephen RahmstoefHe is also at the Potsdam Institute for Climate Impact in Germany, and agrees that under the extreme warming of this century, there may be a weak and shallow AMOC trend left in the world. Some studies even define AMOC disintegration as this type of substantial weakening, he says. “A new study is investigating the remaining wind-driven covers [current] In more detail, this is a valuable contribution to the scientific literature,” he says. “However, in response to human-induced global warming, we will not change our assessment of the risks and impacts of future AMOC changes.”

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Source: www.newscientist.com

Neutrinos shatter records as they tear through the Mediterranean Ocean

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Part of the undersea KM3NET neutrino detector

km3net

The incredibly powerful neutrinos that tore through a new Mediterranean particle detector have amazed physicists, offering a first glimpse into some of the universe’s most intense events, such as the collision of ultrafine black holes.

Neutrinos, sometimes known as “ghost particles,” interact minimally with matter due to their small mass and lack of charge. By placing detectors in dense mediums like water or ice, researchers hope to detect the subtle signals of neutrinos interacting with atoms and producing showers of particles. This, in turn, helps in understanding their properties.

Damian Dornick from the Centre for Particle Physics in Marseille, France, along with his team, discovered the most energetic neutrino ever recorded. Using the Cubic Kilometer Neutrino Telescope (km3net) at the bottom of the Mediterranean Sea, they detected this extraordinary neutrino on February 13, 2023. The discovery left the researchers astonished.

“Initially, we were puzzled,” he says. “As we delved deeper, we realized that this event was truly exceptional, and our excitement grew.”

The signal observed appeared as a bright, almost horizontal line on the detector, believed to be created by muons – small electron-like particles produced by neutrinos interacting with km3net’s detectors.

https://www.youtube.com/watch?v=gpuargix2u4

When the researchers tentatively published their results in 2024, they were still in the process of calculating the exact energy of the particles. “The high energy levels surprised us, as our neutrino simulations had not yet reached such levels,” says Morgan Wasco from Oxford University.

To validate their findings, researchers meticulously considered the impact of other sources of illumination on the detector, such as neutrinos generated by cosmic rays – charged particles from space. These signals are believed to surpass higher-energy neutrinos originating from more distant cosmic sources by 1 to 100 million times.

The energy of the detected neutrino was calculated to be 120 peta electron volts (PEV), about 10 times higher than the previous record set by the IceCube neutrino observatory in Antarctica. Such high-energy neutrino detections offer unique insights into the events producing them, like black hole mergers and supernova explosions.

“While cosmic rays get deflected and lose their original direction as they pass through interstellar space, neutrinos travel straight,” explains Wascko. The relatively large spatial spread of the neutrino’s trail in this case makes pinpointing the exact source challenging, but future enhancements to the telescope could potentially identify similarly powerful neutrinos and their sources.

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Source: www.newscientist.com

Researchers find unusually high levels of cosmic formation beryllium in the Pacific Ocean

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A team of scientists from Helmholtz Senturm Dresden Rossendorf, Tad Dresden Institute of Technology, and the Australian National University have discovered an “unexpected” accumulation of Beryllium-10 from the bottom of the central and North Pacific Oceans.

Col et al. Report on the discovery of anomalies in the beryllium-10 concentration profiles of several deep-sea ferromanganese crusts (stars) from the late Miocene central and North Pacific Oceans. The main bottom (blue line) and surface (red line) ocean currents of the thermal halin circulation are shown. Image credit: Koll et al., doi: 10.1038/s41467-024-55662-4.

Radionuclides are types of nuclei (isotopes) that decay into other elements over time.

They are used to date archaeological and geological samples, and radiocarbon dating is one of the best-known methods.

“The major ocean floors on Earth show one of the most pristine geological archives documenting environmental conditions and changes over millions of years, the ferromanganese crust,” Zentrum Dresden-Rossendorf and his colleagues.

“Dating these marine archives can be achieved through fossils through changes in biostratigraphy, isotope, or elemental composition. Alternatively, we can analyze the imprinted changes in the Earth's magnetic field due to magnetic stratigraphy. Masu.”

“Another commonly employed technique is dating space-forming nuclides,” they added.

“The radionuclide Beryllium-10 is continuously produced in the upper atmosphere, primarily through cosmic ray spallation for nitrogen and oxygen.”

“The residence time of Beryllium-10 in the atmosphere is about 1-2 years for it to adhere to the aerosol and precipitate.”

“In the ocean, atmospheric beryllium-10 mixes with the stable beryllium-9 of the lithosphere, which is transported to the ocean by river runoff and river dust, primarily after erosion of terrestrial minerals.”

Dr. Koll and co-authors have discovered long-term cosmicogenic beryllium-10 anomalies in central and North Pacific samples.

Such anomalies can be attributed to changes in ocean currents or astrophysical events that occurred during the late Miocene era around 10 million years ago.

The findings have the potential to serve as a global time marker for promising advances in dating geological archives over millions of years.

“For a period of millions of years, such space-forming time markers still do not exist,” Dr. Koll said.

“However, this beryllium abnormality can act as such a marker.”

result It will be displayed in the journal Natural Communication.

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D. Koll et al. 2025. Cosmic genome 10It becomes abnormal in the late Miocene as an independent time marker for marine archives. Nut commune 16, 866; doi:10.1038/s41467-024-55662-4

Source: www.sci.news

New research indicates that Jupiter’s moon Io does not have an underground magma ocean

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Juno and Galileo’s volcanic activity on Io, Jupiter’s innermost Galilean moon and the most volcanically active object in the solar system, is unlikely to originate from a global magma ocean just below the surface. Deep space networks and astronomical observations, according to new analysis of Doppler data.

The internal structure of Io revealed by this research. Image credit: Sofia Shen / NASA / JPL / Caltech.

Slightly larger than Earth’s moon, Io is the most volcanically active object in the solar system.

It is the innermost of Jupiter’s Galilean moons, which in addition to Io includes Europa, Ganymede, and Callisto.

Trapped in a gravitational tug of war between Jupiter, Europa, and Ganymede, Io is constantly squeezed, causing frictional heat to build up within its interior, which is thought to be the cause of sustained and widespread volcanic activity.

Volcanic activity on the Moon was first discovered in 1979. That’s when Linda Morabito, an engineer on NASA’s Voyager program, spotted an eruption plume in one of the images taken by the spacecraft during its famous Grand Tour of the outer planets.

Since then, countless observations have been made from both space telescopes and telescopes on Earth documenting Io’s restless nature.

“Io is Galileo’s innermost moon, orbiting Jupiter every 42.5 hours,” said Juno collaborator Dr. Ryan Park of NASA’s Jet Propulsion Laboratory and colleagues.

“It has an average diameter of 3,643 km and a bulk density of 3,528 kg/m.3 As such, it is approximately 5% larger than the Moon, both in diameter and density.”

“Io’s eccentric orbit changes its distance from Jupiter by about 3,500 km, which leads to fluctuations in Jupiter’s gravitational pull.”

“Similar to the Moon’s tides caused by Earth, these gravitational fluctuations cause tidal deformations on Io, which are theorized to serve as the main energy source for the intense volcanism and infrared radiation observed on Io’s surface.”

The amount of tidal energy could be enough to cause Io’s interior to melt, potentially forming a magma ocean underground, but this theory is controversial.

Measuring the extent of Io’s tidal deformation could help determine whether the shallow magma ocean theory is plausible.

“Since the discovery of Morabito, planetary scientists have wondered how volcanoes were fed by lava beneath the Earth’s surface,” said Scott Bolton, Ph.D., principal investigator at Juno and a researcher at the Southwest Research Institute.

“Was there a shallow ocean of white-hot magma that fueled the volcano, or was the source more local?”

“We knew data from Juno’s two very close approaches could give us insight into how this beleaguered satellite actually works.”



Io’s arctic region was captured by NASA’s Juno on December 30, 2023, during the spacecraft’s 57th approach to the gas giant. Image credit: NASA / JPL-Caltech / SwRI / MSSS / Gerald Eichstädt.

NASA’s Juno spacecraft flew very close to Io in December 2023 and February 2024, coming within about 1,500 km of the surface.

During its approach, Juno communicated with NASA’s Deep Space Network and acquired high-precision dual-frequency Doppler data. This data was used to measure Io’s gravity by tracking how it affects the spacecraft’s acceleration.

Combining these observations with archival Doppler data from NASA’s Galileo mission and ground-based telescopes, the researchers calculated how much Io is deformed by tidal forces.

This result is inconsistent with what would be expected if a shallow global magma ocean existed, suggesting that Io has a nearly solid mantle.

It is not yet known whether there are regions of magma deep within the moon.

The findings show that tidal forces do not necessarily create global magma oceans, which could have implications for our understanding of other moons such as Enceladus and Europa.

“Juno’s discovery that tidal forces don’t always produce global magma oceans not only prompts us to rethink what we know about Io’s interior,” Dr. Park said.

“It has implications for our understanding of other moons such as Enceladus and Europa, as well as exoplanets and super-Earths.”

“Our new findings provide an opportunity to rethink what we know about planet formation and evolution.”

The team’s paper published in this week’s magazine nature.

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RS Park others. Due to Io’s tidal reactions, shallow magma oceans do not form. nature published online on December 12, 2024. doi: 10.1038/s41586-024-08442-5

Source: www.sci.news

Deep sea affected by ocean acidification

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Deep sea coral reefs are at risk of acidification

Howard Chu/Alamy Stock Photo

Ocean acidification is penetrating to depths of 1,500 meters, posing new threats to creatures such as sea butterflies, sea snails and cold-water corals.

The ocean is the largest natural sink of carbon dioxide, absorbing about a quarter of our annual emissions. The uptake of CO2 makes the ocean surface more acidic, which affects sensitive ecosystems such as coral reefs. But until now, researchers didn’t know how far acidification was reaching the deep ocean.

jens daniel müller Researchers at the Federal Institute of Technology Zurich in Switzerland have developed a 3D reconstruction of how CO2 moves through the ocean, based on global measurements of ocean currents and other circulation patterns. They used this model to estimate how the carbon dioxide absorbed by the ocean has affected deep-sea acidity since 1800, around the beginning of the industrial revolution.

They found clear acidification signals down to 1,000 meters deep in most of the ocean. In some regions, such as the North Atlantic, where the powerful Atlantic Meridional Overturning Current (AMOC) transports carbon from the surface to the deep ocean, acidification was observed down to 1500 meters. Some pockets of deep water, which are more acidic in nature, showed even more acidification than the surface. Their high natural acidity reduces their ability to absorb added CO2, Mueller says.

This is more or less what researchers expected would happen as the oceans absorbed more carbon dioxide. Wang Hongjie at the University of Rhode Island. “But it’s another thing to actually see the data coming in that affirms this.”

Remarkably, about half of all acidification since 1800 has occurred since 1994, as CO2 emissions have increased exponentially. “We’re seeing this progress be quite rapid,” Muller says.

The scale of acidification is sufficient to threaten the survival of a wide range of life in the oceans. Chiropods such as sea snails and sea butterflies are particularly at risk because their shells are made of calcium, which dissolves when water becomes too acidic. Increasing acidification has doubled the number of areas where it is difficult for cold-water corals to survive.

And ocean acidification will continue as seawater absorbs more carbon dioxide. “Even if we were able to stop carbon dioxide emissions immediately, we would still see ocean acidification processes inland for hundreds of years,” Muller said.

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Source: www.newscientist.com

NASA to investigate subterranean ocean of Uranus’ moon

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Some of the icy moons in the Jupiter and Saturn systems appear to have oceans of liquid water inside them. Although our knowledge of Uranus' moons is more limited, future tours of the Uranian system may be able to detect subsurface oceans. To plan for this, we need to understand how the internal structure of satellites, with and without oceans, relates to observable quantities. New research from the University of Texas Geophysical Institute and the University of California, Santa Cruz shows it may be possible to diagnose the presence or absence of liquid water oceans inside some of Uranus' moons, including Miranda and Ariel. There is, Umbriel, and it is thought that this, combined with measurements of the gravitational field, may provide comprehensive constraints on the internal structure and history of Uranus' moons.

Uranus' four major moons, Ariel, Umbriel, Titania, and Oberon, may have oceanic layers. Salty seas, or salty seas, are found beneath the ice and above water-rich and dry rock layers. Miranda is too small to retain enough heat in the ocean layer. Image credit: NASA/JPL-Caltech.

When NASA's Voyager 2 flew by Uranus in 1986, it took grainy photos of the large icy moon.

Now, NASA plans to send another spacecraft to Uranus, this time equipped to see if those icy moons hide oceans of liquid water.

The mission is still in the early planning stages, but planetary researchers are preparing by building a new computer model that can be used to detect oceans beneath the ice using only the rover's cameras.

Their computer model works by analyzing the moon's tiny vibrations, or wobbles, as it orbits its parent planet.

From there, you can calculate how much water, ice, and rock is inside. A small wobble means the moon is mostly solid, while a large wobble means its icy surface is floating in an ocean of liquid water.

When combined with gravity data, the model calculates the depth of the ocean and the thickness of the overlying ice.

Dr. Doug Hemingway, a planetary scientist at the University of Texas Geophysical Institute, said: “If we find that Uranus' moons have an inland ocean, it means there are a huge number of potentially habitable worlds across the galaxy. It may mean,” he said.

“The discovery of oceans of liquid water on Uranus' moons will change our thinking about the range of possibilities for life.”

All large moons of the solar system, including the moons of Uranus, are tidally locked.

This means that the same side always faces the parent planet while orbiting, as the gravity matches their rotation.

However, this does not mean that the satellite's rotation is completely fixed; all tidally locked satellites will oscillate back and forth during their orbit.

Determining the extent of the wobble is key to learning whether Uranus' moons have oceans, and if so, how large.

A satellite with an ocean of liquid water splashing inside will wobble more than one that is entirely solid. However, even the largest oceans experience only small wobbles. The moon's rotation can shift by just a few hundred feet as it passes through its orbit.

This is still enough for a passing spacecraft to detect it. In fact, this technique was previously used to confirm that Saturn's moon Enceladus has an internal ocean.

To find out whether the same technique would work on Uranus, Dr. Hemingway and his colleague Dr. Francis Nimmo of the University of California, Santa Cruz performed theoretical calculations on Uranus's five moons, using a variety of the most I came up with a plausible scenario.

Detecting smaller oceans means the spacecraft will need to get closer or carry more powerful cameras.

“The next step is to extend the model to include measurements from other instruments and see how this improves the interior of the satellite,” Dr. Hemingway said.

of the team work Published in a magazine Geophysical Research Letters.

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DJ Hemingway and F. Nemo. 2024. Search for the underground ocean inside Uranus's moon using balance and gravity. Geophysical Research Letters 51 (18): e2024GL110409;doi: 10.1029/2024GL110409

This article is a version of a press release provided by the University of Texas.

Source: www.sci.news

Chinese spacecraft discovers more evidence of ancient ocean on Mars

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Topographic map of Mars showing Utopian plains that may have once been an ocean

United States Geological Survey

Possible ancient coastlines have been discovered in a region of Mars explored by China’s Zhurong rover, adding further evidence that vast lowlands in Mars’ northern hemisphere may once have been covered by ocean. The evidence has been obtained.

The rover landed in the southern part of Utopia Plain in May 2021 and remained active for almost a year. Researchers studying data from the rover have found hints that there was an ancient ocean or liquid water 400,000 years ago.

now, Bo Woo Researchers from the Hong Kong Polytechnic University and their colleagues conducted a comprehensive analysis of the topographical features of the landing area by combining remote sensing data from satellites and observations from the spacecraft.

They say they found features consistent with the presence of a southern Utopian coastline, including valleys and sediment channels. They also determined the dating and composition of surface sediments in the area. Based on this, the research team believes that the ocean existed 3.68 billion years ago, but froze and disappeared about 260 million years later.

“This discovery not only provides further evidence in support of the Martian ocean theory, but also perhaps presents for the first time a discussion of its evolutionary scenario,” Wu said.

This area can be divided into a shallow area to the south and a deep area to the north. Wu said shallower parts of the ocean may have been up to 600 meters deep, but there isn’t enough data to estimate the ocean’s maximum depth.

“Water is an important element for life, and the presence of oceans on Mars in the past raises the possibility that Mars may once have harbored early microbial life,” he says.

Mathieu Rapport Researchers at Stanford University in California say whether early Mars had an ocean is a highly debated question with significant implications for the planet’s past habitability. He said future missions will need to test the new findings.

“Utopia Plains may constitute a valuable record of early Martian near-shore and coastal environments,” Rapport says.

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Source: www.newscientist.com

Scientists uncover enigmatic subduction zone beneath Pacific Ocean

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According to a team of geoscientists from the University of Maryland and the University of Maryland, between 250 million and 120 million years ago during the Mesozoic Era, the ancient ocean floor was formed by the East Pacific Rise, a plate boundary at the bottom of the southeastern Pacific Ocean. It is said to have sunk deep into the earth. University of Alberta.

A map of the East Pacific Ridge region where the ancient ocean floor was discovered. Image credit: Jingchuan Wang.

University of Maryland researcher Jingchuan Wang and his colleagues used innovative seismic imaging techniques to look deep into the Earth's mantle, the layer between the Earth's crust and core.

They discovered an unusually thick region in the mantle transition zone at depths of about 410 to 660 km below the Earth's surface.

This zone separates the upper and lower mantle and expands or contracts depending on temperature.

The newly discovered ocean floor may also explain the unusual structure of the Pacific Large Low Shear Velocity Province (LLSVP), a huge region in Earth's lower mantle. Because LLSVP appears to be divided by slabs.

“This thickened area is like a fossil fingerprint of an ancient ocean floor that sank into the Earth about 250 million years ago,” Wang said.

“This gives us a glimpse into Earth's past that we've never seen before.”

Subduction occurs when one tectonic plate slides beneath another and surface material is recycled into the Earth's mantle.

This process often leaves behind visible evidence of movement, such as volcanoes, earthquakes, and deep ocean trenches.

Geologists, on the other hand, typically study subduction by examining rock samples and sediments found at the Earth's surface.

By studying how seismic waves travel through the different layers of the Earth, researchers were able to create a detailed map of the structures hidden deep within the mantle.

“You can think of seismic imaging as similar to a CT scan. Essentially, it allows us to see a cross-section of the Earth's interior,” Dr. Wang said. .

“Typically, chunks of ocean material are completely consumed by the Earth, leaving no discernible traces on the surface.”

“But looking at ancient subducted slabs through this perspective has provided new insights into the relationship between the Earth's very deep structures and surface geology that were not previously clear.”

What the authors discovered surprised them. Matter was moving much more slowly through the Earth's interior than previously thought.

The unusual thickness of this region they found suggests the presence of cold material in this part of the mantle transition zone, where parts of the oceanic slab become stuck in the middle as they sink through the mantle. It suggests that there is.

“We found that material is sinking at about half the rate expected in this region. This may be due to the mantle transition zone acting like a barrier, slowing the movement of material through the Earth. “This suggests something,” Dr. Wang said.

“Our findings raise new questions about how the deep Earth influences what we see at the surface over vast distances and time scales.”

of result Published in a magazine scientific progress.

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Wang Jingchuan others. 2024. Intraoceanic subduction during the Mesozoic era formed the lower mantle beneath the East Pacific uplift. scientific progress 10(39);doi: 10.1126/sciadv.ado1219

Source: www.sci.news

The impact of the melting Greenland Ice Sheet on ocean currents

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Climate change affects our planet and our lives in many ways. Dry the atmosphere To Increase in home runs Climate change accelerates glacial melt with each Major League Baseball season. Greenland Ice Sheet The land ice mass that covers about 80% of Greenland. When glaciers melt, icebergs form, a process called “iceberg formation.” Glacier collapse Recent climate change has increased the rate at which icebergs are flowing from the Greenland Ice Sheet into the North Atlantic.

Scientists have found that in the past, large increases in the rate of glacial collapse have disrupted important ocean current systems in the Atlantic Ocean. Atlantic Meridional Gyre Or as the AMOC, it carries warm water north and cold water south, affecting global temperatures and moving nutrients across the Atlantic Ocean, meaning that disrupting the AMOC could change the climate and destabilize marine ecosystems. Recently, scientists conducted a study to determine whether the current increase in glacier collapse could disrupt the AMOC.

For this study, the researchers developed a method to quantify glacial runoff during past periods of increased glacial collapse in the North Atlantic that disrupted the AMOC. Heinrich Event They began by looking at present-day glaciers in the North Atlantic and the Arctic. As icebergs break up, they deposit sediment. This sediment includes sand and rocks from the land below the ice sheet, as well as the remains of organisms that lived on the ice sheet. When the icebergs melt at sea, the sediment is released and sinks to the ocean floor.

Scientists observed modern glaciers melting and measured the average amount of sediment, by volume, that they released. Using this average, the researchers estimated how much ice was released during past Heinrich events, based on the amount of sediment that was deposited on the floor of the North Atlantic Ocean.

Scientists used this method to estimate the total amount of ice lost during 10 Heinrich events (the last of which) that occurred over the past 140,000 years. Glacial Cycle Previous scientists had determined the duration of Heinrich events, which allowed the researchers to estimate the ice runoff rate during each event. The researchers compared their estimated runoff rates to current ice runoff rates and found that current ice runoff rates are similar to those of previous mid-sized Heinrich events that disrupted the AMOC. However, the scientists who conducted the study also noted that the AMOC is currently stable.

The researchers suggested two factors that could help explain why the current increase in glacial collapse is not disrupting the AMOC as much as it has in the past. First, the researchers think that the AMOC was stronger when the current glacial runoff rate began to increase than it was at the start of past Heinrich events, which may make the current AMOC more resistant to disruptions. Second, each of the 10 Heinrich events the scientists used in their study lasted about 250 years, while the faster glacial collapse seen today may have been due to a slowdown in the early Heinrich events. It began in recent decades They suggested that AMOC collapse could only occur after a longer period of increased glacier calving than has happened previously.

If the rate of glacial calving continues to increase by the time the AMOC collapses, the size of the Greenland Ice Sheet may limit its influence on the AMOC. The researchers noted that if the Greenland Ice Sheet continues to melt at its current rate, the rate of calving will slow before 250 years have passed. The icebergs that caused the Heinrich events in the last glacial cycle broke off from a much larger ice sheet. Laurentide Ice Sheet It no longer exists.

The scientists who conducted the study said that freshwater runoff from the melting Greenland Ice Sheet could also disrupt the AMOC, but its impact would be less severe than ice runoff. However, they noted that freshwater runoff is likely to increase as glacial collapse slows in the coming decades, which could have unpredictable consequences. The researchers suggested that the scientific community should continue their work to model the impacts of a melting Greenland Ice Sheet as accurately as possible, because, in their words, “the fate of the AMOC remains uncertain.”


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Source: sciworthy.com

Potential for a “liquid water ocean” beneath the surface of Mars

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Using new data about the Martian crust collected by NASA’s InSight spacecraft, geophysicists from the University of California, San Diego and the University of California, Berkeley estimate that groundwater could cover the entire planet to a depth of one to two kilometers. Groundwater exists in tiny cracks and pores in rocks in the mid-crust, 11.5 to 20 kilometers below the surface.

A cross section of NASA’s InSight lander and the data it collected. Image courtesy of James Tuttle Keane / Aaron Rodriquez.

“Liquid water existed at least occasionally in Martian rivers, lakes, oceans, and aquifers during the Noachian and Hesperian periods more than 3 billion years ago,” said Dr Vashan Wright of the Scripps Institution of Oceanography at the University of California, San Diego, and his colleagues.

“During this time, Mars lost most of its atmosphere and therefore the ability to support liquid water on its surface for any sustained period of time.”

“Ancient surface water may have been incorporated into minerals, buried as ice, trapped as liquid in deep aquifers, or lost to space.”

For the study, Dr Wright and his colleagues used data collected by InSight during its four-year mission, which ends in 2022.

The lander collected information from the surface directly beneath it about variables such as the speed of Mars’ seismic waves, which allowed scientists to infer what materials exist beneath the surface.

The data was fed into a model based on mathematical theories of rock physics.

Based on this data, the researchers determined that the presence of liquid water in the Earth’s crust was the most plausible explanation.

“If we prove that there is a large reservoir of liquid water, it could give us insight into what the climate was or could be like at that time,” said Professor Michael Manga of the University of California, Berkeley.

“And water is essential for life as we know it. I don’t see why underground reservoirs wouldn’t be habitable environments. On Earth they certainly are. There is life in deep mines, there is life at the bottom of the ocean.”

“We still don’t have evidence of life on Mars, but we’ve identified places that could, at least in principle, support life.”

“A wealth of evidence, including rivers, deltas, lake deposits, and hydrologically altered rocks, supports the hypothesis that water once flowed on the planet’s surface.”

“But that wet period ended more than 3 billion years ago, when Mars lost its atmosphere.”

“Planetary scientists on Earth have sent many probes and landers to Mars to learn what happened to the Martian water (water frozen in the Martian polar ice caps does not explain the whole story), when this happened, and whether life exists or ever existed on Mars,” the authors said.

“The new findings indicate that much of the water has seeped into the crust rather than escaping into space.”

“The new paper analyzes the deeper crust and concludes that the available data are best explained by a water-saturated mid-crust beneath the InSight location.”

“Assuming the crust is similar across the planet, this mid-crustal zone should contain more water than would have filled the hypothetical ancient Martian ocean.”

of Survey results Appears in Proceedings of the National Academy of Sciences.

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Vashan Wright others2024. Liquid water exists in the central crust of Mars. PNAS 121 (35): e2409983121; doi: 10.1073/pnas.2409983121

Source: www.sci.news

Hidden Dark Oxygen on the Ocean Floor Could Revolutionize Evolutionary Rules

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Scientists have made a groundbreaking discovery in the Pacific Ocean that challenges our understanding of Earth’s history and the origin of life. They have found evidence of oxygen production in the deep, lightless depths of the ocean.

The results of this study published in Nature Chemistry challenge the traditional belief that oxygen on Earth is solely produced through photosynthesis.

Lead by Professor Andrew Sweetman, researchers from the Scottish Association for Marine Science (SAMS) made this discovery while exploring the depths of the Clarion-Clipperton Zone, between Hawaii and Mexico.

Named “dark oxygen,” this mysterious phenomenon occurs at depths where light cannot penetrate. The researchers discovered the potential source of this oxygen production while studying polymetallic nodules on the ocean floor, rich in precious metals used in electronics.

These nodules may have the ability to split seawater into hydrogen and oxygen through seawater electrolysis. This finding has significant implications for deep-sea mining activities and the protection of marine habitats.

Director of SAMS, Professor Nicholas Owens, described this discovery as one of the most exciting in marine science, prompting a reevaluation of the evolution of complex life on Earth.

This alternative source of oxygen production challenges the conventional view that cyanobacteria were the first oxygen producers on Earth. It calls for a reconsideration of how complex life evolved and the importance of protecting deep-sea habitats.

To learn more about the experts involved in this research, visit the About the Experts section below.

About the Experts

Andrew Sweetman: Research Group Leader for Benthic Ecology and Biogeochemistry at the Scottish Institute for Marine Science, with extensive experience in deep-sea ecology research.

Nicholas Owens: A marine scientist and Council Member of the Scottish Association for Marine Science, involved in environmental science research and education.

For more information, continue exploring this fascinating discovery and its implications for Earth’s history and marine ecosystems.

Source: www.sciencefocus.com

Rare earth metal-containing minerals on the ocean floor found to be a source of oxygen production, according to scientists

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Researchers from the Scottish Institute for Marine Science have discovered that the deep ocean floor of the Pacific Ocean, covered with polymetallic nodules, produces so-called “dark oxygen.”

Polymetallic nodules recovered from the ocean floor in a Northwestern University lab. Image courtesy of Camille Bridgewater/Northwestern University.

Polymetallic nodules – naturally occurring mineral deposits that form on the seafloor – are commonly found in the sediment-covered abyssal plains of oceans around the world.

These consist primarily of iron and manganese oxides, but also contain metals such as cobalt and rare earth elements, which are essential components of many advanced, low-carbon energy technologies.

For the new study, Dr Andrew Sweetman from the Scottish Institute for Marine Science and his colleagues carried out experiments using chambers placed on the seafloor at a depth of around 4,200 metres to measure oxygen levels at multiple sites more than 4,000 kilometres apart in the Clarion-Clipperton Zone in the central Pacific Ocean, where polymetallic nodules are found.

Nearly every experiment showed a steady increase in oxygen levels over the two days.

The researchers conducted additional laboratory analysis and claim that the source of the detected oxygen release is polymetallic nodules.

Based on numerical simulations, they hypothesize that the electrical properties of the nodes are responsible for oxygen production.

While the researchers note that it is difficult to estimate how much oxygen polymetallic nodules produce over a wide area, they suggest that this source of oxygen may support ecosystems on the deep seafloor, which could be affected if these nodules are mined.

“We understand that oxygen was needed for aerobic life to begin on Earth, and Earth's oxygen supply began with photosynthetic organisms,” Dr Sweetman said.

“But we now know that oxygen is produced even in the deep ocean, where there is no light.”

“So I think we need to rethink questions like where did aerobic life begin.”

of result Published in a journal Nature Chemistry.

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A.K. Sweetman othersEvidence for dark oxygen production on the deep seafloor. National GeographyPublished online July 22, 2024, doi: 10.1038/s41561-024-01480-8

This article is based on a press release provided by Springer Nature and Northwestern University.

Source: www.sci.news

Research shows active hydrothermal systems on small ocean planets have the potential to sustain life

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Ocean worlds are planetary bodies with liquid oceans, often beneath an icy shell or within rocky interiors. In our solar system, several moons of Jupiter and Saturn are ocean worlds. Some ocean worlds are thought to have hydrothermal circulation, where water, rocks, and heat combine to pump and expel fluids to the ocean floor. Hydrothermal circulation influences the chemical composition of the water and rocks of ocean worlds and may help life develop deep beneath the icy surface. In a new study, planetary researchers used computer simulations of hydrothermal circulation based on well-understood systems on Earth to measure the effects of low gravity at values appropriate for ocean worlds smaller than our home planet. Simulations of ocean worlds with (lower) gravity result in fluid circulation that is roughly similar to that which occurs above and below the ocean floor on Earth, but with some key differences. Low gravity reduces buoyancy, so fluids do not become lighter as they heat up, which reduces their flow rate. This increases the temperature of the circulating fluids, which could lead to more extensive chemical reactions, possibly including those necessary to support life.

This diagram shows how Cassini scientists think rocks and water at the bottom of Enceladus’ ocean interact to produce hydrogen gas. Image courtesy of NASA/JPL-Caltech/Southwest Research Institute.

Rock-heat-fluid systems were discovered on the Earth’s ocean floor in the 1970s, where scientists observed releases of fluids carrying heat, particles, and chemicals.

Many of the vents were surrounded by a novel ecosystem, including specialized bacterial mats, red and white tube worms and heat-sensing shrimp.

For the new study, Professor Andrew Fisher from the University of California, Santa Cruz, and his colleagues used a complex computer model based on the hydrothermal cycle that occurs on Earth.

After varying variables such as gravity, heat, rock properties and depth of fluid circulation, the researchers found that hydrothermal vents could persist under a wide range of conditions.

If these flows occurred on an ocean world like Jupiter’s moon Europa, they could increase the chances of life surviving there as well.

“This study suggests that extraterrestrial ocean worlds may have supported low-temperature (but not hot enough for life) hydrothermal systems on timescales similar to those it took for life to become established on Earth,” Prof Fischer said.

The ocean circulation system on which the researchers based their computer model was discovered on the 3.5-million-year-old seafloor of the northwest Pacific Ocean, east of the Juan de Fuca Ridge.

There, cold undersea water flows through an extinct volcano (seamount), travels about 30 miles (48.3 km) underground, and then flows out into the ocean through another seamount.

“As water flows, it picks up heat, it’s warmer than when it entered, and its chemistry changes dramatically,” says Kristin Dickerson, a doctoral student at the University of California, Santa Cruz.

“The flow from seamount to seamount is driven by buoyancy – as water warms it becomes less dense and as it cools it becomes more dense,” Prof Fischer added.

“The difference in density creates a difference in fluid pressure within the rock, and the system is sustained by the flow itself. So as long as there is enough heat supplied and the rock properties allow for sufficient fluid circulation, the system will keep running. We call this a hydrothermal siphon.”

“Hot vent systems are primarily driven by sub-sea volcanism, while the Earth’s ocean floor experiences large amounts of fluid flowing in and out at much cooler conditions, driven primarily by Earth’s background cooling.”

“The flow of water through low-temperature vents is equivalent to all the rivers and streams on Earth in terms of the volume of water released, and accounts for about a quarter of the Earth’s heat loss.”

“About every 500,000 years, the entire volume of ocean water is pumped up and out of the ocean floor.”

Many previous studies of the hydrothermal circulation on Europa and Enceladus have considered hotter fluids.

“Cartoons and other illustrations often depict undersea systems that are similar to Earth’s black smokers, where cooler currents could occur just as much or even more than they do on Earth,” said Dr Donna Blackman from the University of California, Santa Cruz.

The results show that in very low gravity, such as on the ocean floor of Enceladus, the circulation can continue at low to moderate temperatures for millions or billions of years.

This could help explain why small ocean planets can have long-lived fluid circulation systems beneath their seafloors despite limited heating: the inefficiency of heat extraction could extend their lifetimes considerably, potentially for the entire lifetime of the solar system.

Scientists acknowledge that it is uncertain when active hydrothermal systems will be directly observed on the ocean planet’s seafloor.

The distance from Earth and physical characteristics pose significant technical challenges for spacecraft missions.

“It is therefore essential to make the most of the available data, much of which is remotely collected, and to leverage the understanding gained from decades of detailed study of the analog Earth system,” the authors concluded.

their paper Published in Journal of Geophysical Research: Planets.

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A.T. Fisher others2024. Gravitational maintenance of hydrothermal circulation in relation to the ocean world. Journal of Geophysical Research: Planets 129(6):e2023JE008202; doi:10.1029/2023JE008202

Source: www.sci.news

The Methane Ocean on Saturn’s Moon Titan is Causing Coastal Erosion

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Titan's liquid hydrocarbon ocean may have waves

NASA/JPL-Caltech/University of Arizona/University of Idaho

Saturn's largest moon, Titan, has rocky coastlines around its methane seas and lakes that appear to have been carved out by waves, and a NASA mission launching in 2028 may be able to get a closer look.

Titan is the only body in the solar system other than Earth that has liquid on its surface. It has lakes and oceans made of hydrocarbons such as liquid methane, ethane, and other organic molecules. Scientists think that winds in Titan's thick, nitrogen-rich atmosphere drive the waves in these lakes, but this has never been observed directly because Titan's atmosphere is too hazy to see through.

now, Rose Palermo Researchers from the U.S. Geological Survey in Florida and their colleagues found that the shape of Titan's coastline is best explained by the presence of waves that have eroded the ocean surface over eons.

Palermo and his team looked at the shorelines around Titan's largest oceans and lakes, including Kraken Mare and Ligeia Mare, and compared them to coastlines on Earth with known origins, such as Lake Rotoef in New Zealand, which initially formed by floods and later was eroded by waves. The team then created different simulations of Titan's oceans, including those in which the shores were eroded by waves or by dissolving their edges.

Photographed by NASA's Cassini spacecraft, Ligeia Mare on Saturn's moon Titan has a variety of edges that appear to have been carved by waves.

NASA/JPL-Caltech/ASI/Cornell

The researchers found that images of Titan's coastline, best depicted by wave simulations, resemble Earth's wave-eroded coastlines.

“It's still tentative, but I'm very excited about it.” Ingo Muller-Vodarg The Imperial College London researchers say that although the study did not observe waves themselves, it is very strong evidence that waves exist. Dune-like structures.

The only way to truly verify that waves exist is to send a spacecraft to the surface, like NASA's Dragonfly drone mission, scheduled to launch in 2028, Mueller-Vaudergues said.

Studying Titan's coastlines may also help us understand how the first coasts on Earth formed, Palermo says: “Titan is a unique laboratory for studying coastal processes because it is not influenced by humans or plants. It's a place where we can study coasts only as physical processes.”

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Source: www.newscientist.com

SpaceX Starship Launch: Fourth Test Successful with Both Stages Landing Safely in the Ocean

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Starship launched from Boca Chica, Texas.

SpaceX

SpaceX’s Starship, the largest rocket ever, successfully completed its fourth test flight, with the first and second stages completing their missions as planned and each landing in different oceans.

Following liftoff from the SpaceX facility in Boca Chica, Texas, at 7:50 a.m. local time, one of the 33 Raptor engines on Super Heavy’s first stage failed to ignite. Despite this, the rocket continued into space and the two stages separated cleanly.

Super Heavy splashed down on schedule about seven minutes after liftoff, close to the launch site in the Gulf of Mexico. After plummeting to Earth from an altitude of more than 100 kilometers, the booster’s engines ignited normally and it slowed from more than 4,000 kilometers per hour to hover just a few meters above the sea surface, but then the live feed cut out and it plunged into the ocean.

Meanwhile, Starship reached an orbit at an altitude of more than 200 kilometers and traveled at a speed of more than 27,000 kilometers per hour. During its descent to Earth, about 60 kilometers above the surface, SpaceX’s livestream footage showed visible damage to one of its four control fins and what appeared to be a cracked camera lens. As it reached the Indian Ocean, it appeared to hover before plummeting into the water.

This fourth test flight focused on returning Starship from orbit after it had reached space for the first time in the previous test. SpaceX opted to perform a “soft splashdown” at sea, as landing on land is currently considered too risky. Instead, the craft would use its engines to slow its descent, align itself as if it were landing on a base, and then gently splash down on the water.

Eventually, the hope is that spacecraft will be able to be refurbished and reused by returning to land from space, as SpaceX already does with its Falcon 9 rocket.

Today’s launch marks the company’s fourth Starship launch and includes software and hardware upgrades, as well as changes to launch procedures based on lessons learned from previous tests. In the first test in April of last year, the first and second stages exploded before separating, and in another test in November, the second upper stage reached space but stopped transmitting data and self-destructed, and the first stage exploded shortly after separation.

SpaceX’s third Starship test flight on March 14 was at least partially successful, reaching space, conducting a fuel transfer test, and flying farther and faster than ever before, but the spacecraft lost control during the flight and failed to make a planned soft landing.

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Source: www.newscientist.com