Tag Archives: reefs

Coral Reefs Triggered Major Global Warming Events in Earth’s History

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Corals construct their skeletons from calcium carbonate, releasing carbon dioxide as a byproduct.

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For the last 250 million years, coral reef systems have been crucial to the Earth’s climate, but perhaps not in the manner you might assume.

Coral reefs generate excess carbon dioxide because the formation of calcium carbonate, which constitutes coral skeletons, involves the release of greenhouse gases.

Certain plankton species utilize calcium carbonate to form their shells, and when these organisms perish, the mineral becomes buried on the ocean floor. In ecosystems dominated by coral, calcium and carbonate ions that typically nourish deep-sea plankton are rendered inaccessible.

Tristan Salles and his team at the University of Sydney conducted a modeling study on the interactions among shallow corals and deep-sea plankton over the last 250 million years, incorporating reconstructions of plate tectonics, climate simulations, and variations in sediment contribution to the ocean.

They determined that tectonic activity and geographic features foster periods with extensive shallow continental shelves, which provide optimal conditions for reef-building corals, thereby disrupting the coral-plankton dynamics.

As the area covered by coral reefs diminishes, calcium and alkali levels accumulate in the ocean, enhancing plankton productivity and increasing the burial of carbonate in the deep ocean. This shift contributes to lower CO2 concentrations and cooler temperatures.

The study revealed three significant disruptions in the carbon cycle over the past 250 million years. During these events—specifically in the Mid-Triassic, Mid-Jurassic, and Late Cretaceous—extensive coral reefs consumed vast amounts of calcium carbonate, resulting in notable ocean temperature increases.

Once the balance between shallow-sea corals and deep-sea plankton is disrupted, realignment can require hundreds of thousands to millions of years, noted Salles.

“Even if the system recovers from a significant crisis, achieving equilibrium will be a prolonged process, significantly extending beyond human timelines,” Salles elaborated.

On a brighter note, Salles observes that corals excel at absorbing excess nutrients to aid in reef building, even if planktonic nutrient growth gets excessive.

Currently, human-induced carbon dioxide emissions are driving unprecedented global warming and ocean acidification, endangering both corals and plankton, according to Salles. While the outcomes remain uncertain, the potential impact on ecosystems could be catastrophic.

“The feedback mechanisms we modeled span deep time and may not be relevant today. The current rate of change is too rapid for carbonate platform feedbacks to maintain similar significance.”

Alexander Skiles from the Australian National University in Canberra remarks that this research illustrates a “profoundly interconnected feedback cycle between ecosystems and climate.”

He suggested that while species are presumed to evolve and adapt to the climatic conditions dictated by “immutable physical and chemical processes,” it is increasingly evident that certain species are actively shaping the climate itself, leading to co-evolutionary feedback loops.

“Beyond corals, ancient microbial colonies like stromatolites have significantly influenced atmospheric carbon regulation,” Skiles pointed out.

“It is well-recognized that carbon is accelerating climate warming at an alarming rate. Corals contribute to this dynamic over extensive geological time, which may elucidate fluctuations between warmer and cooler periods.”

Source: www.newscientist.com

Coral Reefs Face a Critical Threshold Due to Climate Change

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Coral reefs are critically threatened by climate change

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The recent surge in ocean temperatures has led to extensive bleaching and mortality of warm-water corals globally, marking the onset of the first climate tipping point in an ecosystem on Earth, as stated by scientists.

The deterioration of one of the planet’s most biodiverse and vulnerable ecosystems presents ‘risks to human health and safety’ for which governments are inadequately prepared, cautions Melanie McField, who oversees Florida’s “Healthy Reefs for Healthy People” conservation initiative under the Smithsonian Institution.

Warm-water coral reefs account for one-third of all known marine biodiversity and offer food, coastal protection, and livelihoods for approximately one billion individuals worldwide. Additionally, coral reefs contribute $9.9 trillion annually in goods and services globally.

However, corals are particularly vulnerable to fluctuations in water temperature. Record-breaking global temperatures in 2023 have elevated ocean heat levels to unprecedented highs, resulting in significant bleaching events impacting over 80 percent of the world’s corals. Bleaching occurs when corals react to elevated water temperatures by expelling the algae residing within their tissues, leading them to bleach white. This process can make corals more prone to disease, and prolonged bleaching can deplete their primary food supply, ultimately leading to their death.

The most recent bleaching event represented “an order of magnitude” beyond what scientists had previously witnessed, according to McField. “We are at a tipping point,” she acknowledged. This is generally understood as a crucial threshold that, if crossed, can trigger dramatic and potentially irreversible changes in the climate system.

McField contributed to the chapter on corals in the Global Tipping Point Report 2025, which is now available for purchase. This report, the first update since 2023, was compiled by 160 scientists globally and coordinated by the University of Exeter and campaign organization WWF. It warns that warm-water corals are the initial component of the Earth system to reach a tipping point and are currently facing an “unprecedented crisis.”

Leading experts estimate that the thermal threshold for warm-water corals will be reached at a 1.2 degrees Celsius increase in global atmospheric temperatures above pre-industrial levels, with an upper limit of 1.5 degrees Celsius. By 2024, the world’s average temperature is expected to surpass this 1.5 degrees Celsius threshold for the first time in human history, exceeding the limits within which coral reefs can survive, noted Tim Renton, who spearheaded the report at the University of Exeter.

“We assessed the world at a temperature of 1.5 degrees Celsius and confirmed the results,” he stated during a press conference ahead of the report’s release. “Most coral reefs are at risk of large-scale mortality or bleaching and are transitioning into a different state dominated by seaweed and algae.”

The most promising chance to save the world’s warm-water corals from near-total extinction lies in rapidly reducing global average temperatures to 1.2 degrees Celsius below pre-industrial levels, Renton asserts. However, whether this ambitious goal, which exceeds even the targets set for 1.5°C, is attainable remains uncertain.

Terry Hughes, a researcher from Australia’s James Cook University, emphasizes that “few unbleached coral reefs remain worldwide”. Nonetheless, there is still potential for improvement. “If global greenhouse gas emissions are swiftly curtailed, we can influence the future of coral reefs over the next few decades,” he states.

Although the timing of climate tipping points is often uncertain, researchers caution that significant declines in the Amazon rainforest, melting of polar ice sheets, and collapse of the crucial AMOC current may all occur at warming levels below 2°C.

Moreover, humans can also instigate “positive tipping points” to mitigate these risks, Renton highlighted, pointing to the rapid advancements in renewable energy and the increased adoption of electric vehicles in the past decade. Fast-tracking cleaner technologies could significantly reduce emissions and help keep global warming well below 2°C, the report suggests.

Renton stated that immediate action is crucial from world leaders during the upcoming COP30 summit in Brazil to expedite emissions reductions across the global economy and minimize the duration for which global temperatures exceed 1.5 degrees Celsius. “We are swiftly nearing tipping points in various Earth systems that could have catastrophic impacts on humanity and nature, fundamentally altering the planet. This necessitates immediate and unprecedented action from COP30 leaders and policymakers worldwide,” he urged.

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Source: www.newscientist.com

The most severe bleaching event on record has affected 84% of the world’s coral reefs

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The harmful bleaching of corals around the world has increased to affect 84% of the ocean coral reefs, marking the most intense event in recorded history, as announced by the International Coral Reef Initiative on Wednesday.

This is the fourth global bleaching event since 1998, surpassing the 2014-17 bleaching that impacted two-thirds of the reefs during that time. The current crisis began in 2023, and it remains unclear when it will end, with ocean warming being criticized for the phenomenon.

Mark Eakin, the executive director of the International Coral Reef Association and former coral monitoring officer for the US National Marine and Atmospheric Administration, stated, “We’re witnessing a complete transformation of the planet and its impact on our oceans’ ability to sustain life and livelihoods.”

Last year was reported as the hottest year on record globally, with average sea surface temperatures for oceans away from the poles reaching 20.87 degrees Celsius (69.57 degrees Fahrenheit), which is detrimental to corals. These structures are vital for seafood production, tourism, and protecting coastlines from erosion and storms. Coral reefs are often referred to as “rainforests of the sea” because they host a significant amount of marine biodiversity, with approximately twenty five% of all marine species living in and around them.

Corals house colorful algae, which give them their vibrant hues and serve as a food source. However, prolonged warming causes the algae to release toxins, leading to coral bleaching where they expel the algae and turn white. Weakened corals are at an increased risk of death due to these events, prompting NOAA’s Coral Reef Watch program to introduce additional levels to the bleaching alert scale to convey the heightened risk of coral mortality.

Efforts to conserve coral reefs are underway, such as initiatives to restore coral populations. Dutch labs are working with coral fragments, including those sourced from the Seychelles, with the intention to propagate them in zoos for potential reintroduction to natural reef habitats. Similar projects, including those in Florida, aim to rescue at-risk corals from high temperatures and rehabilitate them before returning them to the sea.

Nevertheless, scientists stress the importance of reducing greenhouse gas emissions like carbon dioxide and methane to combat planet-warming effects and protect coral reefs.

Melanie Mcfield, co-chair of the Caribbean Steering Committee for the Global Coral Reef Surveillance Network, emphasized, “The most effective way to safeguard coral reefs is to address the root causes of climate change by reducing human emissions, primarily from fossil fuel combustion. Inaction poses a significant threat to coral reef ecosystems.”

This update coincides with President Donald Trump’s efforts to bolster fossil fuels and scale back clean energy initiatives as he enters a second term, prompting concerns about the future of coral reefs. Eakin remarked, “The current government is actively dismantling these ecosystems, and eliminating their protections would have catastrophic consequences.”

Source: www.nbcnews.com

Fossils from Mid-Devonian coral reefs shed light on early photosymbiosis evidence

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The symbiotic relationship between corals and their photosynthetic partners, algae (photosymbionts), dates back to at least the Devonian period (385 million years ago), according to a new study.

Dendroid Porites Coral Dendrostella trigeum tab-shaped coral fragments Romerolite Brevis Riphaeus. Image credit: Chong others., doi: 10.1038/s41586-024-08101-9.

All modern corals belong to a group called scleractinians, which evolved during the Triassic period.

These corals may provide habitat for symbionts (such as photosymbionts) that play a role in nutrient recycling, which is especially beneficial in nutrient-poor waters.

However, it is not clear whether earlier extinct forms of coral had photosymbionts.

“The Devonian period (419 to 359 million years ago) was a time when sea surface temperatures and atmospheric carbon dioxide were higher than they are today,” said Jonathan Jung, a researcher at the Max Planck Institute for Chemistry, stated in their paper.

“Unlike today, its carbonate chemistry is dominated by calcite precipitation, likely due to the low magnesium-to-calcium ratio in seawater.”

“The Middle Devonian was the period of greatest expansion of metazoan reefs in the Phanerozoic era, and well-preserved reefs from this period span what is now Europe, North America, North Africa, Australia, Siberia, and China.” explained the researchers.

“In the Devonian period, these reefs bordered the lake seas on the southern margin of Lorsia and the northern boundary of Gondwana.”

“Along the southern margin of Lorsia, these ancient reef communities reached their greatest extent and highest diversity during the Givetian period of the Devonian period (approximately 387 to 382 million years ago).”

“These thriving metazoan coral reefs became diachronically extinct during the course of the Kerwasser crisis in the Late Fraznian (372.2 million years ago).”

“Then, coral reefs were built primarily by cyanobacteria/algae, which were present in very small numbers until the end of the Famenian period (Devonian-Carboniferous boundary).”

“The ability to host photosymbionts was paramount to the ecological success of ancient coral reef communities during the Givetian period, and the subsequent collapse of coral reefs in the Late Devonian was associated with a gradual loss of photosymbiotic relationships. It is suggested that

“However, there is still no clear consensus as to whether photosymbiosis was prevalent in now-extinct coral groups during the Paleozoic era.”

In their study, Dr. Jung and his co-authors examined fossils of two extinct reef coral groups from the mid-Devonian period: the tabula corals and the shibo corals.

They measured nitrogen isotopes bound to corals (15no/14N), can be used to distinguish whether corals obtain energy from photosynthetic symbionts.

Their results suggest that symbionts were present in the tabular corals they studied, but not in most civet corals.

This discovery provides definitive geochemical evidence of the oldest known example of symbiosis in corals.

“Wide-spread oligotrophy during the Devonian may have promoted coral photosymbiosis, and its occurrence may explain why Devonian reefs were the most productive reef ecosystems of the Phanerozoic.” the researchers wrote in their paper.

“These early signals of photosymbiosis in mid-Devonian corals indicate that it supported coral productivity under warm climate conditions.”

“The Late Triassic and Early Miocene (the subsequent period when coral photosymbiosis was reconstructed using nitrogen isotopes) were also warmer than today.”

“In contrast, under modern global warming caused by anthropogenic greenhouse gas emissions, coral bleaching and associated mass mortality events are likely the greatest threat to the future of coral reefs, with the disruption of coral symbiosis due to warming.” It shows that there is.”

“The strength of coral photosymbiosis in past warm climates suggests that the failure of coral symbiosis under ongoing global warming will not be due to an increase in ocean surface temperatures reached, but rather an increase in ocean surface temperatures.” This shows that the rate of increase is greater than the adaptive capacity of the symbiotic relationship.

team's paper appear in the diary nature.

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J. Jung others. Coral photosymbiosis on mid-Devonian coral reefs. naturepublished online October 23, 2024. doi: 10.1038/s41586-024-08101-9

Source: www.sci.news

One controversial proposal to save coral reefs: replace them with new species.

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Would drastic action help the reef recover?

Serge Melessane / Alamy

Corals are being hit hard by global warming, and the only way to save coral reef ecosystems may be to replace native species with more heat-tolerant species from other parts of the world. This is the view of two coral researchers, who call for a thorough evaluation of the benefits and risks of deliberately introducing non-native corals, rather than a quick dismissal.

Living coral is essential to the health of coral reefs and the people who depend on them. Michael Webster Professor at New York University: “Corals are not only beautiful to look at on reefs, they provide habitat for many different organisms, they protect against waves from shorelines, and they make up the sand on tropical beaches.”

But corals cannot tolerate temperatures outside the normal range of their habitat: Global warming has caused ocean temperatures to rise sharply, leading to widespread bleaching, in which corals expel the algal symbionts that provide them with much of their nutrients, and can ultimately lead to their death.

“Coral reefs are being lost at a rapid rate in many places around the world, and attempts to restore them through traditional means have had mixed results,” Webster says.

Webster calls for change in an opinion piece he co-authored with Daniel Schindler of Seattle University in Washington. “You might be able to find corals in a totally different place that are already adapted to the environment that's coming into one place, or that may come into that place in the future — you're trying to find pre-adapted corals,” he says. Many who want to save the reefs are horrified by the idea, but Webster says things are getting worse and it needs to be seriously considered.

For example, two species of branching corals native to the Caribbean are in very poor condition, Webster says. But there are more than 100 species of branching corals around the world, and some of them, if introduced to the Caribbean, could potentially recreate the habitat that the branching corals provided. “They won't necessarily be the same color,” Webster says, “but they're ecologically similar.”

Webster and Schindler acknowledge that there are risks: A worst-case scenario is that devastating diseases or predators are accidentally introduced along with the invasive corals, which could outcompete or hybridize with native species.

But there are also risks in waiting too long to act, Webster says. He thinks that replacing lost species with species that perform a similar role — so-called ecological replacement — is much more realistic than other options currently being considered, such as genetically engineering corals to survive higher temperatures. “The best thing for coral reefs is to maintain the diversity that's there,” he says.

Terry Hughes of James Cook University in Queensland, Australia, disagrees. “The innocuous term 'ecological replacement' is naive, dangerous and stunningly arrogant,” Hughes says. “The authors fail to acknowledge that the accidental or deliberate introduction of invasive species has already caused enormous ecological damage to coral reefs around the world.”

For example, in the 1980s, a previously unknown Pacific disease spread through the entrance to the Panama Canal, wiping out algae-eating sea urchins in the Caribbean and causing an algae bloom that killed millions of corals, Hughes says. “Invasive species are a problem for coral reefs, not a healthy solution.”

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Source: www.newscientist.com

NOAA Declares Fourth Mass Bleaching Event Imminent for World’s Coral Reefs

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Invertebrates are highly sensitive to heat stress, so coral health is closely linked to seawater temperature. Corals turn whitish when stressed. release symbiotic algae They live in organizations. Bleaching indicates that the health of the coral is at risk.

“When a coral bleaches, it doesn’t mean it’s dead. It means it’s weak and at risk of dying if conditions don’t improve,” says Ana Palacio, a scientific assistant at the Oceanic and Atmospheric Research Institute Collaborative Research Institute based at the University of Miami in partnership with NOAA.

Corals are important ecosystems that support a wide variety of fish and aquatic species, helping to nourish coastal communities and attract tourists. The economic value of coral reefs is estimated at $2.7 trillion annually. According to the 2020 report of the Global Coral Reef Monitoring Network.

“They protect our coastlines. They protect us from storms and hurricanes. They have great value to our economy and security,” said Palacio.

Coral ecosystems are among the ecosystems that scientists believe are most at risk from global warming. In 2018, the United Nations Intergovernmental Panel on Climate Change estimated that: 70% to 90% of the world’s coral reefs They will disappear if the average global temperature drops. exceeded the threshold of 1.5 degrees Celsius above the pre-industrial average.

Last year was the hottest year on record on Earth. The average global temperature has approached that threshold for the first time, but scientists believe 2023 was an anomaly, driven by El Niño.

Experts say bleaching began early in the season as sea surface temperatures soared in Florida.

“Typically, bleaching is observed around August to September in the Northern Hemisphere. We started observing the bleaching phenomenon in July last year,” said marine biologist Fanol Montoya Maya from the Coral Restoration Foundation, an organization that collects, restores, and replants coral.

Palacio said the area has seen widespread mortality of elkhorn and staghorn corals, two species that are the focus of restoration efforts.

“In some places, about 20 percent of those populations survived,” Palacio said of the restored corals. “We’re focusing our hopes on why those corals survived and what they can tell us about resistance, and how corals can become more resilient.”

The last global coral bleaching event occurred in 2014 and lasted until 2017. More than 56% of the world’s coral reef areas experienced temperatures that could cause bleaching during that period.

Bleached coral at Flower Garden Banks National Marine Sanctuary off the coast of Galveston, Texas, Gulf of Mexico, September 16, 2023.
LM Otero / AP

Manzello said in an email Monday that 54% of the world’s coral reef areas have experienced bleaching-level heat stress in the past year, and this event could be the worst bleaching event on record.

“The proportion of coral reef areas experiencing bleaching-level heat stress is increasing by about 1% every week,” Manzello said. “This event is likely to exceed the previous peak.”

Montoya-Maya said bleaching warnings were already issued in Florida earlier than last year. He said the Coral Restoration Foundation is preparing for a busy summer in response to new bleaching events.

The natural pattern of El Niño is beginning to disappear, and NOAA’s Climate Prediction Center estimates that an El Niño event is possible. There is a 60% chance of a La Niña event occurring this summer.This could cool the waters of the Atlantic Ocean and allow some corals to recover, at least temporarily.

“This is very heartbreaking and will cause damage to many coral reefs around the world,” Palacio said. “I hope this bleaching event creates some traction and people start to care more and pay attention to what’s happening to the climate.”

Source: www.nbcnews.com

New test shows coral reefs can regrow in as little as four years

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Here is some encouraging environmental news that we all need to hear. Efforts to restore the natural world can yield positive results. A project spearheaded by British and Indonesian scientists has successfully rejuvenated damaged coral reefs in just four years.

Currently, most of the world’s coral reefs are in jeopardy, with some irreparably damaged. However, amidst the concerning reports about the state of our planet’s environment, this recent study provides a glimmer of hope.

Published in the journal Current Biology, the research showcases the capability to increase coral cover and restore essential ecosystem functions rapidly. You can view the paper here.

“The rapid recovery we witnessed was truly remarkable,” commented study author Dr. Ines Lang, a graduate of Exeter University. “We did not anticipate a full restoration of reef framework production within just four years.”

Coral reefs are crucial marine habitats that safeguard coastal regions from storms and erosion. The largest coral reef restoration project in the world is currently underway in South Sulawesi, Indonesia.

The initiative, known as the Mars Coral Reef Restoration Program, involves creating hexagonal “reef stars” (sand-coated steel structures) and affixing young corals to them. These structures are placed in coral reefs damaged by bakutsuri, an explosive fishing method that impairs coral growth. In these areas, coral recovery is impeded without human intervention.

The research team observed coral growth on the structures, with corals adding calcium carbonate to their frames. It was a crucial indicator for scientists to monitor whether reefs were growing or deteriorating based on their carbonate balance.

Within four years, the damaged reefs saw a three-fold increase in their carbonate budget, mirroring that of healthy reefs.

Researchers will continue monitoring the recovered reef’s response to stressors like ocean warming due to climate change. While restoration does not guarantee complete recovery, as restored coral reefs have yet to regain full diversity.

In fact, only one type of coral (branched corals) was transplanted, which are more vulnerable to bleaching. Researchers aim to introduce other coral species to enhance reef diversity.

Lange remarked, “There is no universal solution, but we hope this success story will inspire similar reef restoration projects worldwide.”

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Source: www.sciencefocus.com

Repaired coral reefs will swiftly recover from damage

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Hexagonal frames called Reef Stars are installed in disturbed areas to stabilize loose debris and encourage rapid coral growth.

Maritime Agency

Research findings from a restoration project in Indonesia suggest that restored coral reefs can develop at a rate comparable to healthy coral reefs in just four years. Although quick recovery rates are anticipated, restored reefs tend to have lower species diversity compared to undamaged reefs, raising questions about their long-term survival under more extreme conditions like heat waves. Further studies are required to validate these findings.

Global coral reefs confront a variety of threats, from escalating sea temperatures and ocean acidification to human-related activities such as overfishing.

In the vicinity of Indonesia’s Sulawesi island, coral reefs suffered severe damage approximately three decades ago due to dynamite fishing, a method involving the use of explosives in water to catch large quantities of fish.

According to Tim Lamont from Lancaster University in the UK, “recovery from dynamite fishing does not occur naturally.” The aftermath of this fishing technique leaves a substantial amount of fragmented dead coral skeletons floating, hindering natural coral settlement and growth.

To facilitate the recovery of coral reefs, the Mars Coral Reef Restoration Program has undertaken efforts to restore reefs. As part of Mars’ sustainability initiative, they have deployed sand-coated hexagonal steel structures on the seabed and transplanted them with cuttings from healthy corals. Known as reef stars, these structures stabilize loose debris and promote coral growth.

Simultaneously, Lamont and his team have been monitoring the progress of these initiatives.

One measure of coral health involves examining if the coral’s limestone skeleton grows faster than it erodes. This metric, known as the carbonate budget, signifies the reef’s overall growth rate.

“Four years post the commencement of the restoration process, the reef exhibited growth rates similar to those of healthy reefs,” noted Lamont. “It’s a remarkably rapid recovery.”

However, the composition of the restored coral reef differed from that of a healthy reef, predominantly comprising branched corals. This variance is primarily due to the restoration technique employing branch corals that can be sourced from living corals, entail less damage, and readily adhere to steel structures.

A local community attaches coral fragments to a steel frame as part of a restoration program in Indonesia

Maritime Agency

“Given that branching corals are generally more susceptible to bleaching, variations in communities could result in differing resilience to future stressors, particularly heat stress,” stated team member Ines Lange from the University of Exeter in the UK. “We anticipate that larger and more covered corals will naturally rejuvenate and recover in the restored areas over prolonged periods.”

Lamont emphasized that under stable climate conditions, it is feasible to reconstruct these vital ecosystems. Nevertheless, continued research is essential to assess the recovery of species diversity and the resilience of coral reefs when compared to healthy reefs.

While acknowledging the positive outcomes, members like Michael Bode from Queensland University of Technology, Australia, voiced concerns about the scalability of such projects amidst escalating climate change, the primary threat to coral reefs.

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Source: www.newscientist.com

Using underwater sounds to help coral reefs fight global warming

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2023 was the hottest year ever recorded on Earth. This included oceans around the world, where records fell like dominoes. Last week, about 5,000 scientists gathered in New Orleans for the American Geophysical Union’s biennial marine science conference. Environmental reporter James Dineen was there to take the temperatures of researchers who have been observing changes occurring in the ocean. You can listen to his segment around 05:00 in the embedded player or read the transcript below.

transcript

James Dineen: There was one thing on everyone’s mind at the world’s largest gathering of marine scientists. It’s heat.

England: “Warming over the past few decades, especially in 2023, is sweeping the sector.”

James: Matthew England is an oceanographer at the University of New South Wales in Australia. He was one of thousands of marine scientists who gathered in New Orleans to discuss the latest research on what’s happening in the ocean.

There will be presentations on everything from new species of octopus to robot flying fish. However, rising temperatures are gaining attention.

England: “The burning of fossil fuels, the emission of greenhouse gases into the atmosphere, we know that it is trapped heat, and we know that more than 90 per cent of it escapes into the ocean. I know.”

Last year’s average sea surface temperature broke previous records, rising about 0.2 degrees Celsius above 2022 levels. The amount of heat in the ocean at a depth of 2,000 meters also broke a new record. Then, an abnormal marine heat wave occurred from the Atlantic Ocean to the Sea of Japan.

England: “This was the first year on record where it was difficult to find waters that were not warmer than average.”

Researchers here are working to understand the causes and consequences of that fever.

Let’s consider the mystery of the extent of sea ice in Antarctica. It was surprisingly strong until 2016, but it declined sharply that year. The record low was set again in 2022, but then again in 2023 when the Antarctic winter ice did not recover.

But perhaps the most obvious victim of 2023 temperatures was coral reefs. Large areas of coral, especially around the Florida Keys in the Gulf of Mexico, bleached and died.

Ian Enox of the National Oceanic and Atmospheric Administration studies coral reefs in the Keys. He says seeing so many corals die was a painful experience, but it only drove home the urgency for action.

Enoch: “Some people will see this and feel downtrodden. And I’ve seen people come together and be motivated to actually do something meaningful and be able to confront this issue head on. I’ve seen the exact opposite situation.”

Amy Aprile of Woods Hole Oceanographic Institution in Massachusetts is working on different approaches to restoring coral ecosystems. There are many ideas. But one of her new approaches her team is working on is underwater use. sound.

Apryl: Sound is a basic signal used by coral reef organisms. We understand that it is part of their communication strategy and what they rely on to create a healthy environment. ”

In tests on coral reefs in the Virgin Islands, researchers found that broadcasting underwater recordings of healthy coral reef ecosystems increased the rate at which coral larvae attached to the reef. This could help make coral restoration more effective in the face of rising temperatures.

Apryl: This year has been unprecedented. But the thing that sticks with me and keeps me optimistic is that we’re just getting started and we’re just scratching the surface in putting these solutions into action.

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Source: www.newscientist.com