How waves, ponds and green algae are accelerating sea ice melt in Antarctica

Luke Bennetts, The University of Melbourne; Bonnie Light, University of Washington; Petteri Uotila, University of Helsinki; Philip Reid, Australian Bureau of Meteorology, and Rob Massom, Australian Antarctic Division

Picture sea ice in your mind. You probably imagine brilliant white, snow-covered floes floating on the surface of the ocean, home to penguins in the south of the globe or polar bears in the north.

But our new research shows Antarctic sea ice can turn into rafts of rotting floes (the free-floating pieces of ice) or an icy green slush when it interacts with waves in the stormiest ocean on the planet.

We now know the wave-driven processes that cause the surface of the sea ice to melt are a “missing link” in understanding what’s driving the increasing Antarctic sea ice melt each summer.

These processes can dramatically increase the rate the ice melts, with major implications for the global climate and Antarctic marine ecosystems.

Our planetary heartbeat

Each year, the sea ice that hugs the coast of Antarctica expands from 3 million square kilometres in summer to 19 million square kilometres in winter, stretching far north into the Southern Ocean. As the sun rises and the temperatures increase, it retreats again.

This remarkable seasonal change is like a heartbeat within our planet’s climate system, moderating global temperatures, driving ocean circulation and forming a unique habitat for a plethora of living organisms, all adapted to its seasonal rhythms.

The annual summer sea ice melt is particularly remarkable because it occurs over only three months. But even the most sophisticated climate models underestimate the rapid rate of sea ice retreat each summer.

 

A NASA image from space shows sea ice at its maximum in Antarctica. NASA, CC BY

How do waves melt sea ice?

Until now, the waves travelling from the ice-free ocean into the area covered in sea ice had only been studied for their role in breaking up ice floes. We knew these smaller floes were prone to melting around their sides and bottoms as the ocean was heated by the sun as summer progressed.

But this is not the full story.

We now know waves also flood over ice floes, washing away the bright snow cover that shields the underlying ice from sunlight and creating ponds of seawater on the floe surfaces.

Due to their reduced brightness, the snow-free ice and these “wave ponds” absorb substantially more solar heat than snow-covered ice, and this melts the ice from the top down. Moreover, the snow-free ice and wave ponds are oases in which algae thrive, turning the ice and ponds green and absorbing even more heat from the sun.

The waves also pulverise the floes into small fragments and slush. Under the right conditions, the combination of wave flooding, algal greening and pulverisation turns the sea ice cover into a slushy mixture, resembling a green soup.

We estimate that flooding, ponding and pulverisation can increase summer-time ice thinning by over 4 centimetres per day. Algal greening can add an additional 1 centimetre of thinning per day. These are extraordinary accelerators of ice melt, considering that most Antarctic sea ice is less than 1 metre thick at the end of winter.

Waves are also generated deep within the Antarctic sea-ice region by winds blowing over large openings in the ice cover. In this way, wave melt processes eat away at the ice cover from within, as well as from the edge throughout summer.

 

In this picture of sea ice you can see the effects of wave pulverisation and algae, which darkens the ice. Robert Massom, CC BY-ND

Feedbacks could trigger further melt

Our ice melt estimates are significant, yet they are likely underestimates. They do not account for amplifications to melting caused by so-called “positive feedbacks”.

For example, the ice darkening caused by waves removing the snow, ponding and pulverisation substantially increases the amount of sunlight absorbed by the ice. This causes additional surface and interior melting, which further reduces the ice brightness. And this causes more vertical melting, and so on, in an amplifying cycle.

We propose that this positive feedback is strengthened by algal greening that further darkens the ice, leading to further absorption of sunlight and melting.

Exactly how much these feedbacks would cause further ice melt is tricky to quantify, so we have left this as an exciting future research challenge.

Ponds at both poles

The Antarctic “wave ponds” we have observed are the seawater equivalent of “melt ponds”. These form extensively across Arctic sea ice in summer from pooling snow meltwater.

These freshwater melt ponds have been intensively studied and integrated into climate models, because of their important role in the rapid decline in the coverage and thickness of Arctic sea ice over recent decades.

Unlike melt ponds, seawater wave ponds occur year-round. Although they only occur in regions where sea ice interacts with ocean waves, this encompasses a large proportion of Antarctic sea ice over the course of a year.

The future of Antarctic sea ice

The effects of wave melt, greening and associated feedbacks are likely to intensify on sea ice around Antarctica over coming decades. Climate change is predicted to increase wind speeds and wave heights across the polar Southern Ocean.

This disruption of the annual sea ice cycle and further sea ice loss has serious consequences for global climate and marine ecosystems.

We need further observations using autonomous camera systems on icebreakers and modelling research to better understand these wave processes and their overall influence on Antarctica’s sea ice cycle.

These advances are vital to understanding the causes of recent dramatic sea-ice losses around Antarctica, and promise vital insights about the future of the icy south and our Earth system.

Luke Bennetts, Professor of Applied Mathematics, The University of Melbourne; Bonnie Light, Physicist, University of Washington; Petteri Uotila, Professor, University of Helsinki; Philip Reid, Scientist, Australian Bureau of Meteorology, and Rob Massom, Leader, Sea Ice Section, Antarctic Climate Program, Australian Antarctic Division

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Read More........→June 12, 2026

3 Teens Win Global Earth Prize for Inventing Tamarind Powder That Easily Removes Microplastics

The winners with their Plas-Stick invention, Avyana Mehta, Ariana Agarwal, Vivaan Chhawchharia, and their teacher Minal Jain – credit, the Earth Prize, released

In mid-May, GNN reported that 3 teens from India had won a major continental science prize for their brilliant use of an ingredient in Indian cuisine as the basis for a microplastic filter.

Now, from Geneva comes the announcement that 16-year-olds Vivaan Chhawchharia, Ariana Agarwal, and Avyana Mehta, have claimed the Global Earth Prize in addition to the Asian one, as voted by 23,000 experts from dozens of countries around the world.

“Being named the Global Winners of The Earth Prize is incredibly special for all of us, especially as the first team from India to receive this recognition,” the trio said in a statement.

“What started as an idea between students has now been recognised among thousands of projects from around the world, which feels both surreal and deeply motivating.

Their grand prize-winning invention is called Plas-Stick, and used powdered tamarind seed as the base for an all-natural microplastic clumping agent. After a short agitation period, the clumped microplastic-tamarind mass can be removed with nothing more than a magnet.

Notably, Plas-Stick is the first-ever Global Winner of The Earth Prize from India.

Designed for use in shared water containers, the biodegradable powder binds invisible plastic particles into visible clumps that can then be easily removed with a handheld magnet, offering a simple and low-cost alternative to complex filtration systems.

The idea was sparked by the team’s studies in environmental science and a visit to a rural community, where they observed how drinking water is often stored in shared containers without access to advanced filtration systems.

Globally, over 2.2 billion people lack safely managed drinking water infrastructure, increasing reliance on stored water that may contain microplastics. Microplastics may be the most significant environmental and human health contaminant on Earth. Particles ranging in size from the 1/1 to 1/1,000th the width of human hair have been found virtually everywhere anyone has thought to look for them, including on the summit of Everest and the bottom of the Marianna Trench.

They have been recorded in worryingly high quantities in every human organ and tissue, including the brain and even placenta. Though the full gamut of toxic damage related to microplastic exposure isn’t fully known, what’s certain is that they act as strong endocrine disrupters.

Determined to create a solution that is both effective and accessible, Chhawchharia, Agarwal, and Mehta developed a system that requires no electricity or complex infrastructure. It in fact requires only a crop that’s already used widely in South Asian cuisine, which is both cultivated and thrives in the wild.

“Plas-Stick was designed to be simple, affordable and accessible, and this support allows us to take it beyond pilot schools and scale it to many more communities that need it most!”

Now following their Global Winner recognition, the team plans to scale the solution through decentralised production hubs and expand to rural communities across India, making safer drinking water more accessible across rural Indian communities and beyond.The Earth Prize is run by The Earth Foundation, a non-profit based in Geneva, Switzerland, founded during the School Strike for Climate in 2019. At a time when climate anxiety affects a majority of young people—59% reporting they are very or extremely worried about the environment—the Prize provides a pathway from concern to action, equipping students with the tools to develop tangible, real-world solutions. 3 Teens Win Global Earth Prize for Inventing Tamarind Powder That Easily Removes Microplastics

Read More........→June 05, 2026

70% Drop in Levels of Forever Chemicals Observed in Seabird Eggs Tracks Regulatory Success

Northern gannets on Bonaventure Island – credit, CC 3.0. BY-SA Bodoklecksel

Content of several “forever chemicals” in seabird eggs were found to have sharply decreased over the last 55 years by a team of scientists.

While first rising exponentially from during the 1960s, the chemicals, classed as PFAS, peaked in the 1990s before decreasing in line with regulatory oversight by North American governments.

PFAS are a class of chemicals that form water, stain, and heat-resistant coatings in multiple products which substantially contaminate environments around the world, and are linked to multiple detrimental health outcomes.

A study published in the journal Applied Toxicology that looked at PFAS concentrations in the eggs of northern gannets on Bonaventure Island found that the content of some of the most commonly used PFAS has fallen 70% and sometimes more.

These include perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), which fell 74% and 40% respectively. Concentrations of perfluorohexanesulfonic acid, (PFHxS) another of these chemicals, was also 70% lower from baseline.

“We see this incredible rise to a peak where concentrations seem to be higher than toxicological threshold for those birds, then it really decreases in a nice way,” Raphael Lavoie, a co-author and ecotoxicologist with Environment and Climate Change Canada, told the Guardian. “The regulations are having a good effect.”

The seabird subjects and the long study period were notable strengths. The 55 years of data spans the rise in PFAS production, and the eventual decline as the environmental groups and regulators caught on to the toxicity in the late 90s and early 2000s.

Bonaventure Island is the world’s largest northern gannet breeding colony. These pescatarian birds are directly exposed to PFAS contamination due to the island’s position near the St. Lawrence Seaway, which, being connected to the Great Lakes manufacturing centers north and south of the border, was exposed to substantial amounts of PFAS during the 20th century.

The PFAS got into the fish which got into the gannets and then into their eggs. Tom Perkins for the Guardian wrote that in the late 90s, the chemical corporation M3 dramatically scaled back its production of commercial PFAS in the face of regulatory scrutiny. In 2015, the chemical sector struck an agreement with the EPA to phase out production of PFOA and PFOS, while 6 years earlier at the United Nations’ Stockholm Convention, several of the chemicals tested for in the study were subjected to elimination.

This included PFOA and PFHxS, while PFOS was restricted in everything but firefighting foam.

The study is a comprehensive demonstration of how these regulations are working to reduce the toxic load presented by PFAS in the environment. PFAS are referred to shorthanded as “forever chemicals,” however, and so the authors stress the need for continual environmental and regulatory vigilance, since any similar chemicals entering the environment today will remain, presumably forever. 70% Drop in Levels of Forever Chemicals Observed in Seabird Eggs Tracks Regulatory Success

Read More........→June 01, 2026

Climate change‑related heat increases the risk of premature birth in 13 countries – new study

Dominic Royé, Consejo Superior de Investigaciones Científicas (CSIC); Ana M Vicedo-Cabrera, University of Bern; Aurelio Tobias, Instituto de Diagnóstico Ambiental y Estudios del Agua (IDAEA - CSIC); Carmen Íñiguez, Universitat de València, and Coral Salvador, University of Bern

Picture a sweltering summer’s day. Now imagine enduring the heat while eight months pregnant. Uncomfortable, to say the absolute least.

But in pregnancy, heat is more than just a nuisance, as for many women it can trigger early labour. A premature baby – meaning one born before 37 weeks of gestation – faces a significantly higher risk of mortality, as well as health complications that can affect them for the rest of their lives.

Decades of research has documented the link between exposure to heat and preterm births. However, most studies have been limited to a single city or country, using different methods that yielded results which were difficult to compare.

So how many premature births are actually caused by heat in different parts of the world? Are all pregnant women equally vulnerable? Our new study, published in Environment International, provides the most comprehensive answers to these questions to date.

13 countries, 36 million births

We analysed 36.6 million births that took place during the summer in 250 towns and cities, across 13 countries (Australia, Brazil, Canada, Chile, Ecuador, Estonia, Israel, Italy, Japan, Paraguay, Spain, Switzerland and the United States) between 1979 and 2019. This is the most extensive multi-site analysis conducted on this topic to date.

To estimate the relationship between temperature and the risk of preterm birth, we used cutting edge statistical models that allowed us to see the delayed and non-linear effects of heat exposure in the days leading up to delivery.

The findings are clear: the risk of preterm birth increases linearly as temperatures rise. On days of moderate heat, this risk increases by 2.8%. On days of extreme heat, the increase reaches 3.8%.

855 extra premature births per million

Translating these risks into specific figures provides a clearer picture of the scale of the problem. We estimate that 1.41% of all premature births occurring during the summer are attributable to heat. In absolute terms, this equates to 855 extra premature births per million births.

The magnitude is comparable to that of other well-established factors. For example, it far exceeds the contribution of maternal smoking in low and middle-income countries, and is on a par with that of malaria. And heat is already a major environmental risk factor for reproductive health.

The differences between countries are also revealing. Paraguay has the highest rate, with 1,347 preterm births per million, while Switzerland has the lowest, with 628. Spain falls in the upper-middle range, with 1,080 per million. This variability suggests that climate, the level of socio-economic development, and each country’s capacity to adapt significantly influence the vulnerability of pregnant women.

Not all pregnancies have the same risk

One of our study’s most significant findings suggests that heat may not affect all women equally. Young single mothers with lower levels of education who are in a vulnerable socio-economic situation may be at greater risk of heat-induced preterm birth.

Female foetuses also appear to be more susceptible than male foetuses. However, most of these subgroup analyses were not statistically significant, so further research is needed to confirm them.

There are specific mechanisms behind these differences. People who are economically disadvantaged are more likely to live in particularly hot areas due to the urban heat island effect. They are also more likely to work outdoors, and to lack access to air conditioning or other means of protection against the heat. Social inequality and climate inequality overlap, and the most vulnerable pregnant women pay the highest price.

Heat also speeds up births at term

Perhaps the most surprising finding of our research is that the effect of heat is not limited to preterm births. We have also observed a significant increase in the risk of delivery in pregnancies that would be considered clinically normal, between weeks 37 and 42. Specifically, extreme heat increases the risk of delivery in weeks 37-38 by 3.66%, and in pregnancies of 39 weeks or more by 2.97%.

This means that heat can act as a trigger for labour in foetuses that, under other circumstances, would have continued to develop normally. The most sensitive gestational window is from week 31 to week 40, spanning late preterm and early term births.

Root causes

There are many biological mechanisms at play here. Heat can raise body temperature and trigger uterine contractions. The dehydration caused by heat also disrupts the electrolyte balance and reduces blood flow to the placenta. Furthermore, heat triggers inflammatory processes and oxidative stress, which can compromise foetal development and accelerate cervical ripening.

Pregnant women are particularly vulnerable because their bodies generate more heat than usual due to foetal growth, while also having a reduced ability to dissipate that heat because of weight gain.

Global warming

These findings are particularly worrying in light of climate change. Over the coming decades, heatwaves will become more frequent, more intense, and will last longer. If we fail to act, the burden of preterm births attributable to high temperatures will only increase, undermining decades of progress in neonatal and child health.

A proper response requires action on several fronts. In the clinical setting, health systems must incorporate heat as a risk factor in antenatal care, particularly for socially vulnerable women. In the urban sphere, it is urgent to develop adaptation strategies – green spaces, climate shelters, early warning systems – that protect pregnant women during episodes of extreme heat. And at the policy level, these findings must be translated into ambitious emissions reduction targets.

Extreme heat is no longer just a matter of comfort. It is a question of public health, social equity and climate justice. And pregnant women are on the front line.

Dominic Royé, Investigador Ramon y Cajal, Consejo Superior de Investigaciones Científicas (CSIC); Ana M Vicedo-Cabrera, Head Climate Change & Health research group, University of Bern; Aurelio Tobias, Associate professor, Instituto de Diagnóstico Ambiental y Estudios del Agua (IDAEA - CSIC); Carmen Íñiguez, Profesora en el Departamento de Estadística e Investigación Operativa, Universitat de València, and Coral Salvador, Senior Research Assistant, University of Bern

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Read More........→May 27, 2026

Nest‑building chimpanzees seem to anticipate future weather

Fabiana Rizzi / Unsplash Hassan Al Razi, The University of Western Australia

Every evening, as they move from place to place through the forest, chimpanzees stop to build a nest – most often in a tree – to sleep in. Using a selection of branches, leaves and twigs, they create comfortable and safe spaces to get some shuteye.

Like human beds, these are places to rest – but they also help chimps stay warm or cool and protect themselves against the weather. As you might expect, how and where chimpanzees build their nests depends on things like temperature, humidity, wind and rainfall.

But how do they make these choices? Previous research has shown the construction is related to the conditions at the time when the creatures are building the nest.

In new research, published today in Current Biology, my colleagues and I show that chimps are a little bit cleverer than you might expect: they seem to build their nests in ways that anticipate what the overnight weather will be.

A year in Rwanda

We conducted a field study on eastern chimpanzees in Nyungwe National Park, Rwanda, a cool and humid mountain forest. Over a 12-month period, we collected detailed data on the structure of nests, the characteristics of their chosen sites, and the kinds of trees the chimps chose.

We also measured how well different kinds of nests insulate against cold and heat. At the same time, we made detailed records of weather conditions when the nests were being built and throughout the night.

This let us test whether chimpanzees respond primarily to immediate environmental conditions, or whether their nesting decisions are better explained by the conditions they experience later during the night.

Chimpanzees are always adjusting their behaviour

Our results show chimpanzees consistently adjust their nesting behaviour in relation to environmental conditions. They preferred to build nests in places that were warmer, more humid and less exposed to wind than surrounding areas.

Nest structure and insulation varied systematically with environmental conditions. In cooler and wetter conditions, nests were thicker and deeper – indicating the chimpanzees put more effort into insulation when conditions are tougher.

We also found that factors such as the width and depth of the nest influenced its insulating ability.

The chimpanzees tended to build more insulating nests when weather was colder and when it was more humid, both during nest-building and overnight.

In cooler and wetter conditions, the chimps also built their nests higher, in taller trees with denser leaf cover. This makes sense: it would be a more stable microclimate with more shelter from rain.

Are chimps thinking ahead?

Importantly, nesting decisions aligned more closely with overnight environmental conditions than with those at the time of construction. When we took overnight weather into account, we found we could explain the variation in nesting behaviour much better than if we used only the current conditions.

One possible explanation is that chimpanzees use environmental cues, such as shifts in temperature, humidity or atmospheric pressure, that are linked to upcoming weather.

These cues may allow them to adjust nest-building behaviour in advance. Does this mean they predict or forecast future weather? Not quite.

But it does show their behaviour is consistent with reacting to environmental signals that are associated with later conditions. Either way, the chimps display a remarkable sensitivity to their environment – and a grasp of how to live in it.

Hassan Al Razi, PhD Student, School of Human Sciences, The University of Western Australia

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Read More........→May 01, 2026

How birds are spreading plastic pollution

White storks and gulls feeding at a landfill. Enrique García Muñoz (FotoConCiencia), CC BY-NC-ND

Andy J. Green, Estación Biológica de Doñana (EBD-CSIC); Manchester Metropolitan University

Hungry gulls do not only steal our chips and sandwiches. They learn our habits, and look for reliable sources of food. That includes waste treatment centres, landfill or anywhere food waste is concentrated. Many gull populations have moved inland from the coast to exploit these sources of food.

Wherever our waste is processed, gulls and other birds can forage. At landfills, gulls feed on waste before it is covered up. If there are plastic or glass pieces covered in food that are small enough, gulls will swallow them whole. Only the food itself gets digested, and when the gull flies back to its roost site, the waste gets regurgitated, polluting that site. This movement of pollutants is known as “biovectoring”.

For the first time, scientists like me are now quantifying just how much plastic and other waste is being leaked into important nature areas through the daily movements of birds.

Many lesser black-backed gulls breeding in the UK and other parts of northern Europe migrate to Andalusia in southern Spain, where they form a wintering population of over 100,000 feeding mainly in rice fields and landfills. Fortunately, many of these birds are fitted with GPS tags while breeding. This enables detailed tracking of their movements.

Fuente de Piedra lake in Málaga is a hotspot for migrating lesser black-backed gulls. This wetland has such special natural significance, it’s designated as an internationally important site under a global convention known as Ramsar. It’s most famous for the largest breeding colony of flamingos in Spain. Gulls fly up to 50 miles to landfills to feed, then fly back to roost.

By combining GPS data with waterbird counts, and analyses of regurgitated pellets, scientists have estimated that an average of 400kg of plastics, plus more than two tonnes of other debris such as glass, textiles or ceramics, are deposited by this gull species into the lake each year. This lake has no outflow, making it salty and hence flamingo friendly. Those imported plastics remain in the lake, breaking down into microplastics. They can be ingested by flamingo chicks, aquatic insects and other animals.

Two yellow-legged gulls chase a white stork that is carrying plastic in its bill, which it picked up at a landfill. Enrique García Muñoz (FotoConCiencia), CC BY-NC-ND

In coastal Andalusia, these gulls join the resident yellow-legged gulls (equivalent to our herring gulls) and a mixture of migratory and resident white storks as the three major waterbird visitors to landfills.

In the Cádiz Bay wetlands (another Ramsar site), surrounding the historical city that is now a favourite stop for cruise ships, the three species combine to spread different types and sizes of plastics into different microhabitats. Annually, 530kg of plastics are deposited into wetlands via regurgitated pellets. Although a stork is bigger, so transports more waste per bird, most of the plastic is again moved by the lesser black-backed gulls that winter there in larger numbers.

Plastic film regurgitated by a gull roosting in a field in Atherton, Greater Manchester. Kane Brides, CC BY-NC-ND

This waste ingestion has strong effects on the birds themselves, through direct mortality from diseases, choking or becoming entangled with plastics, and toxic effects of the additives within them. Then after regurgitation in pellets, those plastics are a threat to all fauna and readily enter our food supply through aquaculture and table salt production, both important in Cádiz Bay.

These studies in Spain address a problem that is ongoing all over Europe. There are no comparable quantitative studies yet in the UK, but similar problems occur wherever gulls concentrate to feed on our waste. If white storks become abundant in the UK future, they will probably visit our landfills, together with gulls and perhaps cattle egrets.

The sealing of many landfills, and improvements in waste management may have contributed to recent declines in many gull populations in the UK and elsewhere. But these problems of plastic leakage will continue so long as our consumer society generates so much waste. Reducing waste, and reusing things is better than recycling, partly because food containers may get eaten by birds before they can be recycled. Cleaning our food containers before we bin them, and composting our own food waste, can also help to reduce this phenomenon.

Andy J. Green, Professor of Freshwater Ecology, Estación Biológica de Doñana (EBD-CSIC); Manchester Metropolitan University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Read More........→March 28, 2026

The future remains bleak for corals – but not all reefs are doomed

 

Christopher Cornwall, CC BY-NC-ND

Christopher Cornwall, Te Herenga Waka — Victoria University of Wellington and Orlando Timmerman, University of Cambridge

A recent report on global tipping points warned that coral reefs face widespread dieback and have reached a point from which they cannot recover.

But in our new research, we show this might not be the case for some reefs if corals can gain tolerance to rising temperatures, or if we can cut greenhouse gas emissions and restore reefs with heat-tolerant corals at scale.

Nevertheless, the outlook likely remains bleak.

 

All coral reefs are under threat but some may be more tolerant to warming waters. Christopher Cornwall, CC BY-NC-ND

Coral reefs provide habitat for thousands of other species in tropical oceans. They deliver economic value through fisheries and tourism and provide shoreline protection from storm surges and extreme weather by dampening the impact of waves.

However, coral reefs are vulnerable to the effects of climate change. Our study combines previously published assessments of climate impacts on different coral reefs and reviews the scientific consensus to examine how long reef structures could persist as climate change intensifies.

Ocean warming, acidification, darkening and deoxygenation all threaten the persistence of coral reefs. Ocean warming brings marine heatwaves, which are the leading cause of mass coral bleaching that has led to a global decline in coral cover.

Marine heatwaves have already led to a global decline in coral reefs. Christopher Cornwall, CC BY-NC-ND

Corals are animals that house microalgae within their tissues that provide sugar in exchange for nitrogen. When temperatures become too hot, corals expel these symbiotic microalgae, leaving behind white skeletons.

Ocean acidification reduces the ability of corals to build their skeletons through a process called calcification. Warming, darkening and deoxygenation can also reduce calcification.

When corals expel their symbiotic algae, all that remains are bleached skeletons. Chris Perry, CC BY-NC-ND

Coral reefs are built by adding calcium carbonate, coming mostly from corals but also coralline algae and other calcareous seaweeds. But as the ocean’s pH (a measure of acidity) is reduced, processes called bio-erosion and dissolution act to remove calcium carbonate.

Our meta-analysis examined how climate change affects the calcification and bio-erosion of coral reefs and we then applied these results to a global data set of reef growth.

There is no scientific consensus on which organisms will build future coral reefs. We explore four most likely scenarios:

1. Present-day extreme reefs represent the future of coral reefs. These are locations where temperatures are already warmer, waters are becoming more acidic and oxygen has dropped to conditions similar to those expected at the end of the century. These reefs are dominated by coralline algae and slow-growing heat-resistant corals.

Some reefs already experience conditions expected at the end of the century. Steeve Comeau, CC BY-NC-ND

2. Presently degraded reefs take over future reefs. These reefs are dominated by bio-eroders such as sponges and sea urchins and have low coral cover.

3. Corals can gain heat tolerance to an extent that keeps pace with low to moderate greenhouse gas emissions scenarios. Under these scenarios, only about 36% of global corals would be lost and there would be a moderate reduction in growth. These heat-tolerant reefs are dominated by faster growing corals with symbiotic microalgae that can evolve heat tolerance.

4. Reefs where restoration practices include using heat-tolerant corals that can then disperse to other regions. These restored reefs would have lower coral cover in remote regions lacking restoration or with unsuccessful restoration practices. This kind of reef restoration would need to cover half of global coral reefs to maintain net growth – an unlikely scenario.

We found coral reefs transition to net erosion under all scenarios, even under low to moderate greenhouse gas emissions, meaning they are dissolving or being eaten faster than they can grow. Only reefs with heat-tolerant corals could prevent this from occurring.

The next step for the scientific community is to determine which reefs can persist in the future using global efforts to combine information. The major issues is that we are missing measurements from large parts of the Pacific, and we do not know how deoxygenation or coastal darkening will impact coral reefs. The processes of reef bioerosion and dissolution are also poorly described.

Although the climate has been altered to the point of threatening the future survival of coral reefs, their fate is not doomed yet if we act now.

Another question is how long reef structures will persist after living corals are removed. We do not have an answer yet. It will take global efforts to rapidly obtain these measurements to better manage and protect coral reefs before climate change intensifies.

It is up to governments everywhere, including New Zealand, to better support these initiatives before it is too late.

Christopher Cornwall, Lecturer in Marine Biology, Te Herenga Waka — Victoria University of Wellington and Orlando Timmerman, Doctoral Candidate in Earth Sciences, University of Cambridge

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Read More........→March 16, 2026

Microbes in Antarctica survive the freezing and dark winter by living on air

Ry Holland, Monash University

Winter in Antarctica is long and dark. Temperatures remain well below freezing. In many places, the Sun sets in April and does not rise above the horizon again until August. Without sunlight, photosynthetic life such as plants, mosses and algae cannot make energy.

But that’s not to say all life stops.

In a new study published in The ISME Journal, my colleagues and I show that Antarctic microbes make energy from the air at temperatures as low as –20°C. This finding improves our understanding of how life survives at temperature extremes in Antarctica – and how climate change will affect this important process.

How to make energy from air

In 2017, scientists showed that a large number of Antarctic microbes can generate energy from atmospheric gases present at very low concentrations.

This process is called “aerotrophy”. By using enzymes that are very finely tuned to “sniff out” the hydrogen and carbon monoxide in the atmosphere, these microbes have found a way to make energy from the air itself – a huge advantage in Antarctica’s nutrient-poor desert soils.

What remained unknown until now was the temperature limits of this process. Could aerotrophy be a way to power the continent’s soil communities through the winter?

Taking the lab down south

Measuring how quickly these microbes consume such a small amount of fuel can be difficult.

From 2022–24, we collected surface soil samples from different areas across East Antarctica and analysed them in our lab.

We measured how quickly they can use the atmospheric gases. We also extracted all the DNA from the soil microbes and sequenced it. This tells us what microbes are present, what genes they have, and what they are capable of using as energy sources.

We showed aerotrophy happening in the lab at representative summer (4°C) and winter (–20°C) temperatures. This means hydrogen and carbon monoxide are a viable food source not just over the summer months, but year-round. What was even more surprising though, was the upper temperature limit.

Soil temperatures in Antarctica rarely rise above 20°C. Yet we found microbes in these soils that continued to generate energy from hydrogen up to a staggering 75°C. It seems as though microbes in Antarctic soils are well adapted to the continent’s cold temperatures, but not restricted to them. It’s a bit like seeing a penguin thrive in a tropical jungle.

We also wanted to see this process occurring in Antarctica itself, so two years ago we brought the lab down south. We collected fresh soil samples, sealed them in the glass vials, and took gas samples.

For the first time, it was clear that under real-world conditions these soil microbes were still munching their way through hydrogen.

The primary producers of Antarctica

DNA sequencing has showed us that the vast majority of microbes in Antarctic soils encode the genes to gain energy from hydrogen. Many of these bacteria also have genes to take carbon from the atmosphere.

These aerotrophs are “primary producers”, generating new biomass from the air itself.

In most land-based ecosystems, photosynthesis is thought to be the bottom of the food chain. Photosynthesis takes energy from sunlight and carbon from the atmosphere and turns it into yummy organic compounds.

It’s what makes plants grow. Plants are primary producers that are eaten by herbivores, which are then eaten by carnivores.

In Antarctica’s desert soils, photosynthesis is relatively rare. Instead, we hypothesise that aerotrophy fulfils the primary producer role in many places.

This makes sense because, unlike sunlight-dependent photosythesis, we now know that aerotrophy can happen year-round. Another benefit is that it doesn’t require liquid water, whereas photosynthesis does.

Hydrogen in a heating world

Aerotrophy clearly has an important role in Antarctic ecosystems. So next, we wanted to determine how global warming might affect this process.

Under low-emissions scenarios, we predict a 4% increase in how quickly aerotrophs use atmospheric hydrogen. Under very high-emissions scenarios, this increase rises to 35%. The numbers are similar for carbon monoxide.

Although hydrogen isn’t a greenhouse gas itself, it is important because it affects how long some greenhouse gases, including methane, hang around in the atmosphere.

Soils (including the microbes that live in them) are responsible for 82% of all hydrogen consumed on Earth globally. In other words, they are a hydrogen sink. This is a crucial component in the global hydrogen cycle.

There are a lot of factors that determine how microorganisms will respond to climate change. Temperature is just one of them. This study is an important piece of the puzzle as scientists figure out how resilient Antarctica’s unique microbal ecosystems are.

Ry Holland, Research Fellow in Microbial Ecology, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Read More........→March 12, 2026

Planting Billions of Trees Turned Barren Desert into a Carbon Sink That Lowers CO2

A mixed-species section of the Green Great Wall – Credit: 中国新闻网 CC 3.0. BY

China’s multi-decade long, successful effort to plant a ring of trees around one of the world’s most hostile deserts has sprouted an unexpected benefit to humanity.

Along with protecting the nation’s grasslands and agriculture from the spreading sands of the dismal Taklamakan Desert, the giant ring of trees has turned previous unproductive land into a carbon sink that draws CO2 out of the atmosphere.

It’s thought, and some isolated research has indeed demonstrated, that humans can prevent the worst effects of a rise in average global temperatures by planting trees to absorb more CO2 from the atmosphere.

This strategy has limits, however, when viewed on a global scale. Atmospheric CO2 levels continue to rise, while there is a limit in the amount of land that can be turned over to forests.

One-third of our planet is covered in deserts, where vegetation is sparse or absent, and rainfall is scarce, yet despite their vast acreage they collectively hold less than one-tenth of the world’s carbon stock, or the amount of carbon that is held underground.

A study conducted by NASA and California Technical Institute (Caltech) has used satellite data to demonstrate that the “sea of death” as the Taklamakan Desert was called in antiquity, could be utilized to store carbon and reduce the greenhouse effect.

The Taklamakan Desert. Credit: NASA World Wind 1.4.

Starting in 1978, China’s Three-North Shelter Belt program aimed to plant trees along the borders of the great Taklamakan to stop sandstorms from ruining adjacent pasture and agriculture land. As the world’s single farthest point from any ocean, the Taklamakan is one of the driest and most hostile landscapes on our planet.

The massive Himalayas rise to the south and east, the Pamirs to the southwest, and a pair of mountains known as the Tian Shan and the Altai to the west, leaving landscape completely isolated from moisture.

66 billion trees have been planted by estimates since the start of the Shelter Belt program, which finished in 2024. Monikered the “Green Great Wall,” this incredible increase in greenery has raised average rainfall by several millimeters, resulting in a natural growth of foliage during the wet season that boosts photosynthesis along the tree line, leading to greater degrees of sequestration.

“We found, for the first time, that human-led intervention can effectively enhance carbon sequestration in even the most extreme arid landscapes, demonstrating the potential to transform a desert into a carbon sink and halt desertification,” study co-author Yuk Yung, a professor of planetary science at Caltech and a senior research scientist in NASA’s Jet Propulsion Laboratory, told Live Science in an email.

By precise numbers, it has reduced the average carbon content in the desert air from 416 parts per million to 413 ppm. Parts per million is used as a measurement for the greenhouse effect. Worldwide, the number is 429.3. It was 350 in before the advent of industrialization.If more shelter belt-style tree planting efforts could be used to reclaim desert landscapes, it could open vast areas to absorbing carbon. With little to no vegetation, deserts in their natural state have precious little ability to do so. Planting Billions of Trees Turned Barren Desert into a Carbon Sink That Lowers CO2

Read More........→March 10, 2026

Heat with no end: climate model sets out an unbearable future for parts of Africa

Luis Graterol/Unsplash

Oluwafemi E. Adeyeri, Australian National University

People often think of a heatwave as a temporary event, a brutal week of sun that eventually breaks with a cool breeze. But as the climate changes globally, in parts of Africa, that level of heat is becoming a permanent part of the weather.

Research shows Africa’s exposure to dangerous heat is rising rapidly. Until now, estimating how severe this heat would become was challenging. This was because many widely used global climate models struggled to capture the local factors that shape heat in Africa’s diverse climate zones and habitats (humid tropics, dry savannas and rapidly changing agricultural areas).

It is very important to analyse how these different local factors cause dangerous heat because they all play a role in causing it. For example, rapid changes to the way land is used, such as deforestation, alter soil moisture and humidity. Turning forests into crop land therefore becomes a driver of extreme heat.

We are a team of hydroclimate and land-atmosphere scientists who study heat extremes, water resources, the way land use changes, and hydroclimate risk. We set out to produce reliable, locally relevant projections of future heatwaves. Our team realised that to understand the true heatwave risk in Africa, we had to look down as well as up. It is not only the warming atmosphere from above, it is also the way people are transforming the land below.

To better understand how heat is likely to affect African countries, and to avoid relying on any single climate model, we developed a framework built on four pillars:

• To get the most accurate data, we studied 10 global climate models rather than betting on one model.

• The global climate model outputs were adjusted so they matched observed heatwave patterns (the frequency, duration, magnitude, amplitude, number and timing of heatwaves) and showed the links between temperature, wind, radiation and humidity.

• Artificial intelligence (AI) was used to quantify how much the different drivers of heat (such as temperature, humidity, soil moisture, wind, radiation, land use) contributed to heatwave changes. We also used AI to highlight how these drivers made heat worse when they interacted.

• We compared what would happen in a high-pollution future as opposed to one where governments and industry managed to reduce carbon emissions.

Our research found that by the late 21st century, most regions in Africa will stop having occasional heatwaves and will suffer from extreme heat lasting most of the year. The study shows that by 2065-2100, many parts of Africa (apart from Madagascar) could experience heatwaves on 250-300 days per year.

Some areas, such as the western side of southern Africa, will experience heatwaves that are 12 times as long and frequent as they are now, even if global emissions are reduced. Many heatwaves will last longer than 40 days at a time.

This is not just a slight warming; it is a fundamental change in how people will have to survive on the continent. Once regions in Africa enter a state of almost continuous heatwaves, the human body will have no window of time to recover.

Africa’s heat risk comes from global emissions and local land choices. This means that cutting greenhouse gases matters, and so does protecting and restoring the land’s natural ways of cooling the planet down.

How heat will build dramatically across Africa

In places with intact forests that cool the air, heat and humidity usually remain below a deadly limit. Forests act like natural air-conditioners, preventing fatal heat.

But when forests are cut down and replaced with cropland, the local climate changes. Crops release large amounts of moisture into the air, raising humidity. Heat and moisture build, and the surface heats up faster during the day and stays warmer at night. The land becomes a heat trap. A hot spell that would have been tolerable under forest cover becomes a prolonged, hazardous heatwave.

Rising background heat can affect entire regions. Rural communities, including smallholder farmers, are also highly exposed because they work outdoors and often have limited access to cooling, healthcare or heat-resilient infrastructure.

Heatwaves will affect shack or informal settlement areas more because they generally lack trees and vegetation, and homes built from metal are harder to cool. Without shade, heat will build and linger.

A ‘deadly threshold’ will be reached

Our modelling shows that there is a specific combination of heat and humidity where conditions can intensify heatwaves very quickly, especially in landscapes dominated by cropland.

This is a different kind of heat risk. It is not the familiar “dry heat” driven by parched soils. It is a crop‑driven humidity effect that pushes the atmosphere into a danger zone. For example, in west Africa, extreme heat will peak at about 26.5°C-26.8°C with 74%-75% humidity, producing heatwaves that last 30-35 days.

In southern east Africa, heatwaves will happen even at lower temperatures (23.6°C-23.8°C) and humidity (70%-72%). The danger there is that even small increases in heat or moisture, including those caused by cutting down forests, will make heatwaves more common and longer.

Across all nine African climate regions, our research found that heatwaves will stop being rare events and start becoming a regular part of the year.

The good news is that local land choices will offer immediate protection. Keeping forests, restoring vegetation and using climate-smart farming (where animals and crops are farmed with trees) are not just environmental actions. They are public health defences that weaken the intensity and duration of heatwaves.

What needs to happen next

This research highlights something simple but powerful: a forest is a shield.

This study also shows how planning in cities and in rural areas can keep “nature’s air‑conditioner” working.

Protecting the continent means acting on two fronts. Globally, we need to keep reducing fossil fuel emissions, because even moderate cuts lower the chance of long, near-permanent heatwaves.

Locally, every land-clearing decision matters. Removing natural vegetation adds heat to communities, but keeping forests and cover on the land helps hold temperatures down.

The message is straightforward. Countries cannot control global warming on their own, but they can control how the land responds to it.

Oluwafemi E. Adeyeri, Research Fellow in Climate Science, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Read More........→February 18, 2026

Polar bears are adapting to climate change at a genetic level – and it could help them avoid extinction

Alice Godden, University of East Anglia: The Arctic Ocean current is at its warmest in the last 125,000 years, and temperatures continue to rise. Due to these warming temperatures more than two-thirds of polar bears are expected to be extinct by 2050 with total extinction predicted by the end of this century.

But in our new study my colleagues and I found that the changing climate was driving changes in the polar bear genome, potentially allowing them to more readily adapt to warmer habitats. Provided these polar bears can source enough food and breeding partners, this suggests they may potentially survive these new challenging climates.

We discovered a strong link between rising temperatures in south-east Greenland and changes in polar bear DNA. DNA is the instruction book inside every cell, guiding how an organism grows and develops. In processes called transcription and translation, DNA is copied to generate RNA (molecules that reflect gene activity) and can lead to the production of proteins, and copies of transposons (TEs), also known as “jumping genes”, which are mobile pieces of the genome that can move around and influence how other genes work.

In carrying out our recent research we found that there were big differences in the temperatures observed in the north-east, compared with the south-east regions of Greenland. Our team used publicly available polar bear genetic data from a research group at the University of Washington, US, to support our study. This dataset was generated from blood samples collected from polar bears in both northern and south-eastern Greenland.

Our work built on the Washington University study which discovered that this south-eastern population of Greenland polar bears was genetically different to the north-eastern population. South-east bears had migrated from the north and became isolated and separate approximately 200 years ago, it found.

Researchers from Washington had extracted RNA from polar bear blood samples and sequenced it. We used this RNA sequencing to look at RNA expression — the molecules that act like messengers, showing which genes are active, in relation to the climate. This gave us a detailed picture of gene activity, including the behaviour of TEs. Temperatures in Greenland have been closely monitored and recorded by the Danish Meteorological Institute. So we linked this climate data with the RNA data to explore how environmental changes may be influencing polar bear biology.

Does temperature change anything?

From our analysis we found that temperatures in the north-east of Greenland were colder and less variable, while south-east temperatures fluctuated and were significantly warmer. The figure below shows our data as well as how temperature varies across Greenland, with warmer and more volatile conditions in the south-east. This creates many challenges and changes to the habitats for the polar bears living in these regions.

In the south-east of Greenland, the ice-sheet margin, which is the edge of the ice sheet and spans 80% of Greenland, is rapidly receding, causing vast ice and habitat loss.

The loss of ice is a substantial problem for the polar bears, as this reduces the availability of hunting platforms to catch seals, leading to isolation and food scarcity. The north-east of Greenland is a vast, flat Arctic tundra, while south-east Greenland is covered by forest tundra (the transitional zone between coniferous forest and Arctic tundra). The south-east climate has high levels of rain, wind, and steep coastal mountains.

Temperature across Greenland and bear locations

Author data visualisation using temperature data from the Danish Meteorological Institute. Locations of bears in south-east (red icons) and north-east (blue icons). CC BY-NC-ND

How climate is changing polar bear DNA

Over time the DNA sequence can slowly change and evolve, but environmental stress, such as warmer climate, can accelerate this process.

TEs are like puzzle pieces that can rearrange themselves, sometimes helping animals adapt to new environments. In the polar bear genome approximately 38.1% of the genome is made up of TEs. TEs come in many different families and have slightly different behaviours, but in essence they all are mobile fragments that can reinsert randomly anywhere in the genome.

In the human genome, 45% is comprised of TEs and in plants it can be over 70%. There are small protective molecules called piwi-interacting RNAs (piRNAs) that can silence the activity of TEs.

Despite this, when an environmental stress is too strong, these protective piRNAs cannot keep up with the invasive actions of TEs. In our work we found that the warmer south-east climate led to a mass mobilisation from these TEs across the polar bear genome, changing its sequence. We also found that these TE sequences appeared younger and more abundant in the south-east bears, with over 1,500 of them “upregulated”, which suggests recent genetic changes that may help bears adapt to rising temperatures.

Some of these elements overlap with genes linked to stress responses and metabolism, hinting at a possible role in coping with climate change. By studying these jumping genes, we uncovered how the polar bear genome adapts and responds, in the shorter term, to environmental stress and warmer climates.

Our research found that some genes linked to heat-stress, ageing and metabolism are behaving differently in the south-east population of polar bears. This suggests they might be adjusting to their warmer conditions. Additionally, we found active jumping genes in parts of the genome that are involved in areas tied to fat processing – important when food is scarce. This could mean that polar bears in the south-east are slowly adapting to eating the rougher plant-based diets that can be found in the warmer regions. Northern populations of bears eat mainly fatty seals.

Overall, climate change is reshaping polar bear habitats, leading to genetic changes, with south-eastern bears evolving to survive these new terrains and diets. Future research could include other polar bear populations living in challenging climates. Understanding these genetic changes help researchers see how polar bears might survive in a warming world – and which populations are most at risk.

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Alice Godden, Senior Research Associate, School of Biological Sciences, University of East Anglia

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Read More........→December 23, 2025

What our missing ocean float revealed about Antarctica’s melting glaciers

Pete Harmsen, CC BY-ND

Steve Rintoul, CSIRO; Esmee van Wijk, CSIRO; Laura Herraiz Borreguero, CSIRO, and Madelaine Gamble Rosevear, University of Tasmania

Sometimes, we get lucky in science. In this case, an oceanographic float we deployed to do one job ended up drifting away and doing something else entirely.

Equipped with temperature and salinity sensors, our Argo ocean float was supposed to be surveying the ocean around the Totten Glacier, in eastern Antarctica. To our initial disappointment, it rapidly drifted away from this region. But it soon reappeared further west, near ice shelves where no ocean measurements had ever been made.

Drifting in remote and wild seas for two-and-a-half years, the float spent about nine months beneath the massive Denman and Shackleton ice shelves. It survived to send back new data from parts of the ocean that are usually difficult to sample.

Measurements of the ocean beneath ice shelves are crucial to determine how much, and how quickly, Antarctica will contribute to sea-level rise.

Argo floats are autonomous floats used in an international program to measure ocean conditions like temperature and salinity. Peter Harmsen, CC BY-ND

What are Argo ocean floats?

Argo floats are free-floating robotic oceanographic instruments. As they drift, they rise and fall through the ocean to depths of up to 2 kilometres, collecting profiles of temperature and salinity. Every ten days or so they rise to the surface to transmit data to satellites.

These floats have become a mainstay of our global ocean observing system. Given that 90% of the extra heat stored by the planet over the past 50 years is found in the ocean, these measurements provide the best thermometer we have to track Earth’s warming.

Little buoy lost

We deployed the float to measure how much ocean heat was reaching the rapidly changing Totten Glacier, which holds a volume of ice equivalent to 3.5 metres of global sea-level rise. Our previous work had shown enough warm water was reaching the base of the ice shelf to drive the rapid melting.

To our disappointment, the float soon drifted away from Totten. But it reappeared near another ice shelf also currently losing ice mass and potentially at risk of melting further: the Denman Glacier. This holds ice equivalent to 1.5m of global sea-level rise.

The configuration of the Denman Glacier means it could be potentially unstable. But its vulnerability was difficult to assess because few ocean measurements had been made. The data from the float showed that, like Totten Glacier, warm water could reach the cavity beneath the Denman ice shelf.

Our float then disappeared under ice and we feared the worst. But nine months later it surfaced again, having spent that time drifting in the freezing ocean beneath the Denman and Shackleton ice shelves. And it had collected data from places never measured before.

The Denman Glacier in east Antarctica. Pete Harmsen, CC BY-ND

Why measure under ice?

As glaciers flow from the Antarctic continent to the sea, they start to float and form ice shelves. These shelves act like buttresses, resisting the flow of ice from Antarctica to the ocean. But if the giant ice shelves weaken or collapse, more grounded ice flows into the ocean. This causes sea level to rise.

What controls the fate of the Antarctic ice sheet – and therefore the rate of sea-level rise – is how much ocean heat reaches the base of the floating ice shelves. But the processes that cause melting in ice-shelf cavities are very challenging to observe.

Ice shelves can be hundreds or thousands of metres thick. We can drill a hole through the ice and lower oceanographic sensors. But this is expensive and rarely done, so few measurements have been made in ice-shelf cavities.

The Denman and Shackleton glaciers. NASA, CC BY-ND

What the float found

During its nine-month drift beneath the ice shelves, the float collected profiles of temperature and salinity from the seafloor to the base of the shelf every five days. This is the first line of oceanographic measurements beneath an ice shelf in East Antarctica.

There was only one problem: because the float was unable to surface and communicate with the satellite for a GPS fix, we didn’t know where the measurements were made. However, it returned data that provided an important clue. Each time it bumped its head on the ice, we got a measurement of the depth of the ice shelf base. We could compare the float data to satellite measurements to work out the likely path of the float beneath the ice.

These measurements showed the Shackleton ice shelf (the most northerly in East Antarctica) is, for now, not exposed to warm water capable of melting it from below, and therefore less vulnerable.

However, the Denman Glacier is exposed to warm water flowing in beneath the ice shelf and causing the ice to melt. The float showed the Denman is delicately poised: a small increase in the thickness of the layer of warm water would cause even greater melting.

What does this mean?

These new observations confirm the two most significant glaciers (Denman and Totten) draining ice from this part of East Antarctica are both vulnerable to melt caused by warm water reaching the base of the ice shelves.

Between them, these two glaciers hold a huge volume of ice, equivalent to five metres of global sea level rise. The West Antarctic ice sheet is at greater risk of imminent melting, but East Antarctica holds a much larger volume of ice. This means the loss of ice from East Antarctica is crucial to estimating sea level rise.

Both the Denman and Totten glaciers are stabilised in their present position by the slope of the bedrock on which they sit. But if the ice retreated further, they would be in an unstable configuration where further melt was irreversible. Once this process of unstable retreat begins, we are committed. It may take centuries for the full sea-level rise to be realised, but there’s no going back.

In the future, we need an array of floats spanning the entire Antarctic continental shelf to transform our understanding of how ice shelves react to changes in the ocean. This would give us greater certainty in estimating future sea-level rise.

Steve Rintoul, CSIRO Fellow, CSIRO; Esmee van Wijk, Vanwijk, CSIRO; Laura Herraiz Borreguero, Physical oceanographer, CSIRO, and Madelaine Gamble Rosevear, Postdoctoral Fellow in Physical Oceanography, University of Tasmania

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Read More........→December 16, 2025