Scale of microplastics in Antarctic revealed in preliminary survey results

(Image: IAEA)

By Alex Hunt, World Nuclear News, in Vienna

The first results of the pioneering scientific research project launched earlier this year have catalogued microplastic particles in the sea water, sediment and animals in Antarctica.

The preliminary results were outlined during an International Atomic Energy Agency (IAEA) General Conference session focusing on the study, which is supported by Argentina and forms part of the wider IAEA NUTEC plastics initiative, which aims to use nuclear technologies to tackle plastic pollution.

Nathalie Bernard, from the IAEA Marine Environment Laboratories and University of Buenos Aires, unveiling the results, said that "sadly we have found microplastics everywhere, on every sample, every matrix". She said that the concentrations of microplastics varied by location and by day.

More than 250 samples were collected from the Almirante Irizer icebreaker, which sailed 27,209 kilometres over 125 days covering 84 sampling stations. Over the course of a week 166 samples were collected from Argentina's Carlini research station base as part of what was described as the first study of microplastics pollution from South America to Antarctica.

The samples were of water, of sediment and also of penguin droppings and shellfish. Bernard said: "All of these results were possible thanks to nuclear techniques, specifically vibrational microspectroscopy which allows us not only to count, but also identify polymers. We were able to analyse particles as small as 20 microns (WNN note: for comparison a human hair is about 100 microns) and this is important because we found out that almost 90% of the particles we analysed were smaller than 100 microns and ... most of the studies conducted before have focused on larger particles, larger than 300 microns, which clearly overlooks the larger majority."

The preliminary results - with 30% of the samples analysed so far, found that in terms of distribution in water, in Buenos Aires it was 256 microplastic particles per litre, compared with 5 microplastics particles per litre in the Antarctic Ocean and 21 microplastics particles per litre at Carlini Station in the Antarctic.

The Carlini samples found 6000-15,000 microplastic particles per kilogramme of sediment, 15 microplastic particles per square metre of sand and 200-4000 microplastic particles per biological sample of shellfish or penguin droppings.

The prevalence and type of microplastics was shown to the session (Image: WNN photo/IAEA/Bernard slide)

There were 11 different types of plastics found in the samples, 62% were "Teflon-like microplastics" and 29% were polyethylene-like. Examples of the types of products using the types of plastics found included frying pans, PVC pipes and plastic drinks bottles.

The early theories about the possible sources of the pollution in Antarctica include fisheries, local human activities and global sources, via the atmosphere or ocean currents.

Bernard said that the conclusions of the preliminary study was that "we know now that microplastics are everywhere, that we can find different levels and types between the sites and that the levels in Antarctica are relatively low if we compare them with highly populated industrial zones - but they are far away from zero, which is what it was thought to be until recently in Antarctica.".

The next steps are to finalise the analysis and do extra checks before sharing the results globally and using the figures as a baseline for future surveys, to assess possible pollution sources and inform policy makers for local and global actions in line with the Antarctic Treaty.

The meeting also heard progress reports on the United Nations actions to end plastics pollution and how the NUTEC initiative can help with plastics upcycling using irradiation to allow plastic waste to not just be traditionally recycled, but also used in cement or in wood/plastic composits - one of the examples given was Argentina using radiation-modified railway sleepers from plastic waste.

Argentina's Foreign Affairs Minister Diana Mondino said that the country was one of the original signatories of the Antarctic Treaty and said: "There's growing concern in understanding the impact in the Antarctic ecosystem from plastics and microplastics." She said the results had prompted the creation of a regional group in Latin America led by Argentina to focus on the issue.

IAEA Director General Rafael Mariano Grossi said the NUTEC initiative had been well received because "we do have a serious problem with microplastics, nanoplastics and we did also have a scarcity of information, objective information". He said having the facts was important so people can take "informed decisions when it comes to the protection of this environment, which is so pristine and that we all care for".

"This is not a simple environmental endeavour that we take for the sake of knowing a little bit more - the idea is that we provide important information that is relevant for fisheries, relevant for very important economic activities in all our countries."

Australia's ambassador Ian Biggs said that Australia had a major stake in the international effort in Antarctica and he said that according to projections there could soon be a tonne of plastic in the ocean for every three tonnes of fish, saying this showed the necessity of action to tackle plastic pollution and he said Australia believed that the NUTEC programme was "making a real difference in helping countries address pressing global challenges on plastic pollution".

More than 400 samples were taken during the study (Image: Still from IAEA video)

The background

The IAEA's NUTEC plastics scheme was established in 2020 and uses a series of monitoring laboratories to use nuclear technology to sample and analyse microplastics - which are bits of plastic less than 5 millimetres in diameter - in the environment. There are more than 60 countries participating in monitoring of microplastics in the sea, and the goal is to equip more than 50 laboratories with the technology to form a global monitoring network.

The aim is to then be able to take action to bring in measures designed to reduce the sources of the pollution - at least 30 countries are involved in developing innovative recycling technology, including using irradiation to treat plastics and make them fit for reuse, or for a wider range of reuses. This process uses gamma and electron beam radiation technologies to modify certain types of plastic waste, breaking down plastic polymers judged not to be of sufficient quality into smaller components and then allowing them to be used to generate new plastic products.

The IAEA cites studies suggesting that only around 10% of plastic produced between 1950 and 2015 has been recycled, with the majority (about 60%) going to landfill, meaning action is imperative given estimates that there will be one tonne of plastic for every three tonnes of fish within a few years.

Grossi visited an IAEA mission in Antarctica in January with Argentina's president to see the start of work for the project, with the IAEA explaining that "there is still almost no information available on where and how much microplastics arrive in the Antarctic and how much is taken up by Antarctic organisms. There is also very little data existing on the types of microplastics reaching this pristine area through ocean currents, atmospheric deposition and the presence of humans in the Antarctic".It also said the "presence of microplastics can contribute to accelerating the ice-loss in Antarctica by reducing ice reflectivity, altering surface roughness, promoting microbial activity, acting as thermal insulators, and contributing to mechanical weakening of the ice structure". Scale of microplastics in Antarctic revealed in preliminary survey results

Read More........→August 14, 2025

Antarctica has a huge, completely hidden mountain range. New data reveals its birth over 500 million years ago

Jacqueline Halpin, University of Tasmania and Nathan R. Daczko, Macquarie University

Have you ever imagined what Antarctica looks like beneath its thick blanket of ice? Hidden below are rugged mountains, valleys, hills and plains.

Some peaks, like the towering Transantarctic Mountains, rise above the ice. But others, like the mysterious and ancient Gamburtsev Subglacial Mountains in the middle of East Antarctica, are completely buried.

The Gamburtsev Mountains are similar in scale and shape to the European Alps. But we can’t see them because the high alpine peaks and deep glacial valleys are entombed beneath kilometres of ice.

How did they come to be? Typically, a mountain range will rise in places where two tectonic plates clash with each other. But East Antarctica has been tectonically stable for millions of years.

Our new study, published in Earth and Planetary Science Letters, reveals how this hidden mountain chain emerged more than 500 million years ago when the supercontinent Gondwana formed from colliding tectonic plates.

Our findings offer fresh insight into how mountains and continents evolve over geological time. They also help explain why Antarctica’s interior has remained remarkably stable for hundreds of millions of years.

A radar image showing the Gamburtsev mountain range under layers of ice. Creyts et al., Geophysical Research Letters (2014), CC BY-SA

A buried secret

The Gamburtsev Mountains are buried beneath the highest point of the East Antarctica ice sheet. They were first discovered by a Soviet expedition using seismic techniques in 1958.

Because the mountain range is completely covered in ice, it’s one of the least understood tectonic features on Earth. For scientists, it’s deeply puzzling. How could such a massive mountain range form and still be preserved in the heart of an ancient, stable continent?

Most major mountain chains mark the sites of tectonic collisions. For example, the Himalayas are still rising today as the Indian and Eurasian plates continue to converge, a process that began about 50 million years ago.

Plate tectonic models suggest the crust now forming East Antarctica came from at least two large continents more than 700 million years ago. These continents used to be separated by a vast ocean basin.

A map of the topography (a) and surface elevation (b) of Antarctica, measured in metres above sea level; (c) shows ice thickness in metres. Pritchard et al., Scientific Data (2025), CC BY

The collision of these landmasses was key to the birth of Gondwana, a supercontinent that included what is now Africa, South America, Australia, India and Antarctica.

Our new study supports the idea that the Gamburtsev Mountains first formed during this ancient collision. The colossal clash of continents triggered the flow of hot, partly molten rock deep beneath the mountains.

As the crust thickened and heated during mountain building, it eventually became unstable and began to collapse under its own weight.

Deep beneath the surface, hot rocks began to flow sideways, like toothpaste squeezed from a tube, in a process known as gravitational spreading. This caused the mountains to partially collapse, while still preserving a thick crustal “root”, which extends into Earth’s mantle beneath.

Mountain building causes deep crustal rocks to deform, fold and partially melt. Jacqueline Halpin

Crystal time capsules

To piece together the timing of this dramatic rise and fall, we analysed tiny zircon grains found in sandstones deposited by rivers flowing from the ancient mountains more than 250 million years ago. These sandstones were recovered from the Prince Charles Mountains, which poke out of the ice hundreds of kilometres away.

Zircons are often called “time capsules” because they contain minuscule amounts of uranium in their crystal structure, which decays at a known rate and allows scientists to determine their age with great precision.

These zircon grains preserve a record of the mountain-building timeline: the Gamburtsev Mountains began to rise around 650 million years ago, reached Himalayan heights by 580 million years ago, and experienced deep crustal melting and flow that ended around 500 million years ago.

Most mountain ranges formed by continental collisions are eventually worn down by erosion or reshaped by later tectonic events. Because they’ve been preserved by a deep layer of ice, the Gamburtsev Subglacial Mountains are one of the best-preserved ancient mountain belts on Earth.

While it’s currently very challenging and expensive to drill through the thick ice to sample the mountains directly, our model offers new predictions to guide future exploration.

Geologists Jacqueline Halpin and Jack Mulder stand on the Denman Glacier during recent fieldwork. Jacqueline Halpin

For instance, recent fieldwork near the Denman Glacier on East Antarctica’s coast uncovered rocks that may be related to these ancient mountains. Further analysis of these rock samples will help reconstruct the hidden architecture of East Antarctica.

Antarctica remains a continent full of geological surprises, and the secrets buried beneath its ice are only beginning to be revealed.

Jacqueline Halpin, Associate Professor of Geology, University of Tasmania and Nathan R. Daczko, Professor of Earth Science, Macquarie University

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

Read More........→May 14, 2025

Scientists in Antarctica: why they’re there and what they’ve found

David William Hedding, University of South Africa

A media storm blew up in mid-March 2025 when a researcher at South Africa’s isolated Sanae IV base in Antarctica accused one of its nine team members of becoming violent.

The Conversation Africa asked geomorphologist David William Hedding, who has previously carried out research from the frozen continent, about the work researchers do in Antarctica, what conditions are like and why it matters.

What do researchers focus on when they’re working in Antarctica?

Currently, the main focus of research in the Antarctic revolves around climate change because the White Continent is a good barometer for changes in global cycles. It has a unique and fragile environment. It’s an extreme climate which makes it highly sensitive to any changes in global climate and atmospheric conditions. Importantly, the Antarctic remains relatively untouched by humans, so we are able to study processes and responses of natural systems.

Also, the geographic location of Antarctic enables science that is less suitable elsewhere on the planet. An example of this is the work on space weather (primarily disturbances to the Earth’s magnetic field caused by solar activity). Studying space weather is significant because the magnetic field of the Earth can impact communication platforms, technology, infrastructure and even human health.

How many countries have teams working there? Where does South Africa fit in?

Currently, about 30 countries have research stations in the Antarctic but these bases serve a far wider community of researchers. Collaboration is a key component of research in the Antarctic because many study sites are isolated, logistics are a challenge and resources are typically limited.

The South African base in Antarctica, named SANAE IV usually has between 10 and 12 researchers and base personnel. This research station is situated on a nunatak (a mountain piercing through the ice) in Western Dronning Maud Land. It is an extremely remote location approximately 220km inland from the ice-shelf.

The researchers and base personnel remain in Antarctica for approximately 15 months working through the cold and dark winter months.

What have been some of the biggest ‘finds’?

The biggest research finding from the Antarctic was the discovery of the ozone hole in 1985 by scientists from the British Antarctic Survey. This discovery led to the creation and implementation of the Montreal Protocol, a treaty to phase out chlorofluorocarbons (synthetic chemical compounds composed of chlorine, fluorine, and carbon) which destroy ozone. This was a major breakthrough in terms of slowly healing the ozone layer.

The second most significant piece of research to come from the Antarctic has been the use of ice cores to reconstruct past climates. Ice cores preserve air bubbles which provide a wealth of information about the conditions of the atmosphere over time. Importantly, ice cores provide an uninterrupted and detailed window into the past 1.2 million years. This is important because only by understanding past climates and the earth’s responses to those changes are we able to predict future responses. This is significant because of the imminent threats resulting from anthropogenic (human-induced) climate change.

What conditions do scientists work under?

Conducting research in the Antarctic is extremely difficult for three primary reasons: remoteness, the cold and daylight.

The remoteness of many study sites makes it difficult to reach. Distances are vast from the limited number of bases in the Antarctic. Thus, logistics for science in the Antarctic is a major challenge and requires collaboration and planning. For example, the geologists from the University of Johannesburg, who work from the SANAE IV base in Antarctica, often spend weeks in the field collecting samples. They travel significant distances via snow mobile and remain self-sufficient while conducting science in tough conditions.

These tough conditions relate specifically to the cold. Most science only occurs in the austral summer months when temperatures become marginally bearable. Also, the summer season only provides a short window in which to operate because access to Antarctic by sea is limited by extent and thickness of the sea ice.

Lastly, during summer there is 24 hours of daylight which lengthens the working day but these conditions are also short-lived.

Why it is important to do scientific work in the area?

The Antarctic is intricately linked to global systems and plays a major role in influencing these systems.

For example, climate change will cause significant melting of land-based ice in Antarctica which when added to the oceans will cause sea-level rise and disruptions to global oceanic currents. Therefore, it is critical that we obtain a better understanding of how responses of terrestrial systems, such as the Antarctic, will impact oceanic systems because ultimately changes in ocean currents will impact the oceanic food web.

In the context of climate change, sea-level rise is a major concern as it will have global impacts for society, so it is critical that the impacts are investigated to enable society to build resilience and adapt.

David William Hedding, Associate Professor in Geography, University of South Africa

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

Read More........→April 03, 2025

Scientists in Antarctica: why they’re there and what they’ve found

David William Hedding, University of South Africa

A media storm blew up in mid-March 2025 when a researcher at South Africa’s isolated Sanae IV base in Antarctica accused one of its nine team members of becoming violent.

The Conversation Africa asked geomorphologist David William Hedding, who has previously carried out research from the frozen continent, about the work researchers do in Antarctica, what conditions are like and why it matters.

What do researchers focus on when they’re working in Antarctica?

Currently, the main focus of research in the Antarctic revolves around climate change because the White Continent is a good barometer for changes in global cycles. It has a unique and fragile environment. It’s an extreme climate which makes it highly sensitive to any changes in global climate and atmospheric conditions. Importantly, the Antarctic remains relatively untouched by humans, so we are able to study processes and responses of natural systems.

Also, the geographic location of Antarctic enables science that is less suitable elsewhere on the planet. An example of this is the work on space weather (primarily disturbances to the Earth’s magnetic field caused by solar activity). Studying space weather is significant because the magnetic field of the Earth can impact communication platforms, technology, infrastructure and even human health.

How many countries have teams working there? Where does South Africa fit in?

Currently, about 30 countries have research stations in the Antarctic but these bases serve a far wider community of researchers. Collaboration is a key component of research in the Antarctic because many study sites are isolated, logistics are a challenge and resources are typically limited.

The South African base in Antarctica, named SANAE IV usually has between 10 and 12 researchers and base personnel. This research station is situated on a nunatak (a mountain piercing through the ice) in Western Dronning Maud Land. It is an extremely remote location approximately 220km inland from the ice-shelf.

The researchers and base personnel remain in Antarctica for approximately 15 months working through the cold and dark winter months.

What have been some of the biggest ‘finds’?

The biggest research finding from the Antarctic was the discovery of the ozone hole in 1985 by scientists from the British Antarctic Survey. This discovery led to the creation and implementation of the Montreal Protocol, a treaty to phase out chlorofluorocarbons (synthetic chemical compounds composed of chlorine, fluorine, and carbon) which destroy ozone. This was a major breakthrough in terms of slowly healing the ozone layer.

The second most significant piece of research to come from the Antarctic has been the use of ice cores to reconstruct past climates. Ice cores preserve air bubbles which provide a wealth of information about the conditions of the atmosphere over time. Importantly, ice cores provide an uninterrupted and detailed window into the past 1.2 million years. This is important because only by understanding past climates and the earth’s responses to those changes are we able to predict future responses. This is significant because of the imminent threats resulting from anthropogenic (human-induced) climate change.

What conditions do scientists work under?

Conducting research in the Antarctic is extremely difficult for three primary reasons: remoteness, the cold and daylight.

The remoteness of many study sites makes it difficult to reach. Distances are vast from the limited number of bases in the Antarctic. Thus, logistics for science in the Antarctic is a major challenge and requires collaboration and planning. For example, the geologists from the University of Johannesburg, who work from the SANAE IV base in Antarctica, often spend weeks in the field collecting samples. They travel significant distances via snow mobile and remain self-sufficient while conducting science in tough conditions.

These tough conditions relate specifically to the cold. Most science only occurs in the austral summer months when temperatures become marginally bearable. Also, the summer season only provides a short window in which to operate because access to Antarctic by sea is limited by extent and thickness of the sea ice.

Lastly, during summer there is 24 hours of daylight which lengthens the working day but these conditions are also short-lived.

Why it is important to do scientific work in the area?

The Antarctic is intricately linked to global systems and plays a major role in influencing these systems.

For example, climate change will cause significant melting of land-based ice in Antarctica which when added to the oceans will cause sea-level rise and disruptions to global oceanic currents. Therefore, it is critical that we obtain a better understanding of how responses of terrestrial systems, such as the Antarctic, will impact oceanic systems because ultimately changes in ocean currents will impact the oceanic food web.

In the context of climate change, sea-level rise is a major concern as it will have global impacts for society, so it is critical that the impacts are investigated to enable society to build resilience and adapt.

David William Hedding, Associate Professor in Geography, University of South Africa

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

Read More........→March 26, 2025

Melting Antarctic ice will slow the world’s strongest ocean current – and the global consequences are profound

Taimoor Sohail, The University of Melbourne and Bishakhdatta Gayen, The University of Melbourne

Flowing clockwise around Antarctica, the Antarctic Circumpolar Current is the strongest ocean current on the planet. It’s five times stronger than the Gulf Stream and more than 100 times stronger than the Amazon River.

It forms part of the global ocean “conveyor belt” connecting the Pacific, Atlantic, and Indian oceans. The system regulates Earth’s climate and pumps water, heat and nutrients around the globe.

But fresh, cool water from melting Antarctic ice is diluting the salty water of the ocean, potentially disrupting the vital ocean current.

Our new research suggests the Antarctic Circumpolar Current will be 20% slower by 2050 as the world warms, with far-reaching consequences for life on Earth.

The Antarctic Circumpolar Current keeps Antarctica isolated from the rest of the global ocean, and connects the Atlantic, Pacific and Indian oceans. Sohail, T., et al (2025), Environmental Research Letters., CC BY

Why should we care?

The Antarctic Circumpolar Current is like a moat around the icy continent.

The current helps to keep warm water at bay, protecting vulnerable ice sheets. It also acts as a barrier to invasive species such as southern bull kelp and any animals hitching a ride on these rafts, spreading them out as they drift towards the continent. It also plays a big part in regulating Earth’s climate.

Unlike better known ocean currents – such as the Gulf Stream along the United States East Coast, the Kuroshio Current near Japan, and the Agulhas Current off the coast of South Africa – the Antarctic Circumpolar Current is not as well understood. This is partly due to its remote location, which makes obtaining direct measurements especially difficult.

Understanding the influence of climate change

Ocean currents respond to changes in temperature, salt levels, wind patterns and sea-ice extent. So the global ocean conveyor belt is vulnerable to climate change on multiple fronts.

Previous research suggested one vital part of this conveyor belt could be headed for a catastrophic collapse.

Theoretically, warming water around Antarctica should speed up the current. This is because density changes and winds around Antarctica dictate the strength of the current. Warm water is less dense (or heavy) and this should be enough to speed up the current. But observations to date indicate the strength of the current has remained relatively stable over recent decades.

This stability persists despite melting of surrounding ice, a phenomenon that had not been fully explored in scientific discussions in the past.

What we did

Advances in ocean modelling allow a more thorough investigation of the potential future changes.

We used Australia’s fastest supercomputer and climate simulator in Canberra to study the Antarctic Circumpolar Current. The underlying model, ACCESS-OM2-01, has been developed by Australian researchers from various universities as part of the Consortium for Ocean-Sea Ice Modelling in Australia.

The model captures features others often miss, such as eddies. So it’s a far more accurate way to assess how the current’s strength and behaviour will change as the world warms. It picks up the intricate interactions between ice melting and ocean circulation.

In this future projection, cold, fresh melt water from Antarctica migrates north, filling the deep ocean as it goes. This causes major changes to the density structure of the ocean. It counteracts the influence of ocean warming, leading to an overall slowdown in the current of as much as 20% by 2050.

Far-reaching consequences

The consequences of a weaker Antarctic Circumpolar Current are profound and far-reaching.

As the main current that circulates nutrient-rich waters around Antarctica, it plays a crucial role in the Antarctic ecosystem.

Weakening of the current could reduce biodiversity and decrease the productivity of fisheries that many coastal communities rely on. It could also aid the entry of invasive species such as southern bull kelp to Antarctica, disrupting local ecosystems and food webs.

A weaker current may also allow more warm water to penetrate southwards, exacerbating the melting of Antarctic ice shelves and contributing to global sea-level rise. Faster ice melting could then lead to further weakening of the current, commencing a vicious spiral of current slowdown.

This disruption could extend to global climate patterns, reducing the ocean’s ability to regulate climate change by absorbing excess heat and carbon in the atmosphere.

Ocean currents around the world (NASA)

Need to reduce emissions

While our findings present a bleak prognosis for the Antarctic Circumpolar Current, the future is not predetermined. Concerted efforts to reduce greenhouse gas emissions could still limit melting around Antarctica.

Establishing long-term studies in the Southern Ocean will be crucial for monitoring these changes accurately.

With proactive and coordinated international actions, we have a chance to address and potentially avert the effects of climate change on our oceans.

The authors thank Polar Climate Senior Researcher Dr Andreas Klocker, from the NORCE Norwegian Research Centre and Bjerknes Centre for Climate Research, for his contribution to this research, and Professor Matthew England from the University of New South Wales, who provided the outputs from the model simulation for this analysis.

Taimoor Sohail, Postdoctoral Researcher, School of Geography, Earth and Atmospheric Sciences, The University of Melbourne and Bishakhdatta Gayen, ARC Future Fellow & Associate Professor, Mechanical Engineering, The University of Melbourne

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

Read More........→March 17, 2025

DNA detectives in Antarctica: probing 6,000 years of penguin poo for clues to the past

Jamie Wood, University of Adelaide and Theresa Cole, University of Adelaide

Studies of ancient DNA have tended to focus on frozen land in the northern hemisphere, where woolly mammoths and bison roamed. Meanwhile, Antarctica has received relatively little attention. We set out to change that.

The most suitable sediments are exposed near the coast of the icy continent, where penguins like to breed. Their poo is a rich source of DNA, providing information about the health of the population as well as what penguins have been eating.

Our new research opens a window on the past of Adélie penguins in Antarctica, going back 6,000 years. It also offers a surprise glimpse into the shrinking world of southern elephant seals over the past 1,000 years.

Understanding how these species coped with climate change in the past can help us prepare for the future. Wildlife in Antarctica faces multiple emerging threats and will likely need support to cope with the many challenges ahead.

A unique marine ecosystem

Adélie penguins are particularly sensitive to changes in their environment. This makes them what we call a “sentinel species”, providing an early warning of imbalance or dysfunction in the coastal ecosystem. Their poo also provides a record of how they responded to changes in the past.

In our new research, we excavated pits up to 80cm deep at ten Adélie penguin colonies along the 700km Ross Sea coastline. We then collected 156 sediment samples from different depths in each excavation.

Six of these colonies were still active, meaning birds return annually to breed. The other four had been abandoned at various times over the past 6,000 years.

From these sediments we generated 94 billion DNA sequences, which provided us with an unparalleled window into the past lives of Adélie penguins and their ecosystem.

We detected the DNA of several animal species besides Adélie penguins. These animals included two other birds, three seals and two soil invertebrates.

Not all of this DNA came from penguin poo. Our samples also contained DNA from feathers, hairs or skin cells of other species in the environment at the time.

Sediment samples were taken from ten penguin colonies of various ages, six active (white dot) and four abandoned (coloured dot), on the coast of Ross Sea in Antarctica. Wood, J., et al (2025) Nature Communications, CC BY-NC-ND

Penguin population size and diet

When we took a closer look at the DNA from penguins of the present day, we found more genetic diversity in samples from larger colonies.

Recognising this relationship between genetic diversity and colony size enabled us to estimate the size of former colonies. We could also reconstruct population trends through time.

For example, in samples from active colonies, we found penguin genetic diversity increased as we sampled closer and closer to the surface. This may reflect population growth over the past century.

The DNA also revealed changes in penguin diets over time. Over the past 4,000 years, the penguins in the southern Ross Sea switched from mainly eating one type of fish – the bald notothen – to another, Antarctic silverfish.

The bald notothen lives beneath the sea ice, so this prey-switching was likely driven by a change in sea ice extent compared with the past.

Surprise! Elephant seals

We made an unexpected discovery at Cape Hallett, in the northern Ross Sea. This is the site of an active penguin colony.

Samples of sediment from close to the surface contained lots of penguin DNA and eggshell. But samples from further down, where penguin DNA and eggshell were scarce, contained DNA from southern elephant seals.

Today, elephant seals are uncommon visitors to the Antarctic continent, and breed on subantarctic islands including Macquarie, Campbell and Antipodes Islands. Yet, bones of elephant seal pups found along the Ross Sea coast indicate the species used to breed in the area.

Carbon dating of these bones indicate elephant seal colonies began disappearing from the southern Ross Sea around 1,000 years ago. Over the following 200 years, colonies in the northern Ross Sea began vanishing too.

As the climate cooled and the extent of sea ice increased, elephant seals could no longer access suitable breeding sites. These sites were then taken over by Adélie penguins who expanded into areas once occupied by seals.

Our DNA evidence suggests Cape Hallett was one of the last strongholds of southern elephant seals on the icy continent. But we may yet again see elephant seals breeding on the Antarctic mainland as the world warms and sea ice melts.

Even more ancient DNA in Antarctica

Our study spans the past 6,000 years, but our research suggests it would be possible to go even further back.

The DNA fragments we found were very well preserved, showing little of the damage expected in warmer climates.

So it should be possible to obtain much older DNA from sediments on land in Antarctica – maybe even 1 million-year-old DNA, as recently reported from Antarctic sediments beneath the ocean floor.

Worthy of lasting protection

In December 2017, 2.09 million square kilometres of the Ross Sea and adjoining Southern Ocean became the world’s largest marine protected area. Establishing the protection was a major achievement, yet it was only afforded for 35 years.

After 2052, continuation of the region’s protected status will require international agreement. Knowledge of the vulnerability of local species and their risk in the face of change will play a key role in informing the decision. Our research provides a case study for how ancient environmental DNA can contribute towards this understanding.

Jamie Wood, Senior Lecturer in Ecology and Evolution, University of Adelaide and Theresa Cole, Postdoctoral technician in environmental DNA, University of Adelaide

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

Read More........→March 11, 2025

More Than 50,000 Pounds of Trash Removed from the Arctic in 2023

credit – Protection of the Arctic Marine Environment

Over 50,000 pounds of trash have been removed from the Arctic in 2023 after a multilateral effort flooded critical northern ecosystems with volunteers.

Working during the brief Arctic summer, clean-up operations were carried out in Alaska, Greenland, Norway, and Iceland.

Nearly 2,000 volunteers were enlisted across the treaty nations of the Arctic Council, an inter-governmental panel on peaceful and sustainable use and protection of the Arctic zone formed by the nations that pierce its frozen borders, and the indigenous peoples that call it home.

The council is divided into working groups that address certain issues, and the Protection of the Arctic Marine Environment (PAME), founded in 1991, partnered with the Ocean Conservancy and various local groups like Keep Norway Clean to organize this sizable operation through its Arctic Cleanup initiative.

These annual clean-ups have removed over 100,000 pounds of trash between 2021 and 2023. The overwhelming majority of trash originates in the fishing industry, Keep Norway Clean reports.

Arctic cleanup is both challenging and costly, the government-funded nonprofit writes. Long distances, difficult-to-access areas, scattered populations, short cleanup seasons, and limited access to waste management, are the main challenges for voluntary cleanup in Arctic areas. More Than 50,000 Pounds of Trash Removed from the Arctic in 2023

Read More........→February 25, 2025

Antarctica Yields Intact Skull — An Ancestor of Today’s Waterfowl That Survived Dinosaur Extinction

An artist’s impression of Vegavis iaai, an ancestor of modern waterfowl – credit: Mark Witton / SWNS

A modern-looking diving bird was living somewhere in Antarctica when a massive asteroid struck the Earth and caused the dinosaurs to go extinct.

But unlike the dinosaurs, this early ancestor of today’s waterfowl survived that mass extinction event, and a nearly complete skull has now been recovered by a special paleontological project on the southern continent.

The animal is called Vegavis iaai—a Late Cretaceous diving bird which lived at the same time that Tyrannosaurus rex was dominating North America.

The skull exhibits a long, pointed beak and a brain shape unique among all known birds previously discovered from the Mesozoic Era—the epoch stretching from 252 to 66 million years ago, and comprising the Triassic, Jurassic, and Cretaceous Periods.

Researchers say the features place Vegavis in the group that includes all modern birds, representing the earliest evidence of a now widespread and successful evolutionary radiation across the planet.

Assistant Professor of Biology Chris Torres from the University of the Pacific acquired the fragments of the animal’s skull from a geology sample obtained during a 2011 expedition by the Antarctic Peninsula Paleontology Project.

Meticulously extracted and scanned into a 3D rendering, Torres said it was like trying to complete a 3D jigsaw puzzle without having a box to use as a reference.

“The pieces that are left, some of them are torn in half, some of those are missing pieces. Even then—you don’t know the picture on the box, right?” he told the Univ. of the Pacific press. “You know what other pictures on other boxes look like, and you’re using those to predict what this one looked like. I think it scratches the same itch a jigsaw puzzle does, but the stakes are much higher.”

The professor, who recently published an analytical study on the skull, added that the scale of the discovery is likely to trigger sizeable debates about where it fits in the story of modern birds.

Professor Christopher Torres at University of the Pacfic, and lead author on the discovery – credit: Ben Spiegel, UoP

“Few birds are as likely to start as many arguments among paleontologists as Vegavis,” he said. “Chief among them: where is Vegavis perched in the bird tree of life?”

Vegavis was first reported 20 years ago by study co-author Dr. Julia Clarke, of the University of Texas, Austin, and several colleagues. At that time, it was proposed as an early member of modern birds that was evolutionarily nested within waterfowl.

But modern birds are exceptionally rare before the Cretaceous extinction, and more recent studies have cast doubt on the evolutionary position of Vegavis. Several traits—including the shape of the brain and beak bones—are consistent with modern birds, specifically waterfowl.

Unlike most of today’s waterfowl, the research team says the skull preserves traces of powerful jaw muscles useful for overcoming water resistance while diving to snap up fish. It also leans more towards the feeding patterns of today’s grebes and loons rather than that of ducks or geese, as the features of its feet are more consistent with underwater propulsion.

Antarctica may have served as a refuge, protected by its distance from the turmoil taking place elsewhere on the planet and enriched by a temperate climate with lush vegetation.

“This fossil underscores that Antarctica has much to tell us about the earliest stages of modern bird evolution,” said professor at Ohio University and co-author Patrick O’Connor.

He says birds known from elsewhere on the planet at around the same time are “barely recognizable” by modern bird standards.

“And those few places with any substantial fossil record of Late Cretaceous birds, like Madagascar and Argentina, reveal an aviary of bizarre, now-extinct species with teeth and long bony tails, only distantly related to modern birds.”“Something very different seems to have been happening in the far reaches of the Southern Hemisphere, specifically in Antarctica.” Antarctica Yields Intact Skull — An Ancestor of Today’s Waterfowl That Survived Dinosaur Extinction

Read More........→February 21, 2025

Scientists Drill Ice Core–2 Miles Down–Extracting 1.2 Million Years of Climate Record On Earth

Antarctica ice core – PNRA / IPEV via SWNS

An international team of scientists in the Antarctic has successfully extracted what is believed to be the world’s oldest ice—a historic milestone for climate science.

They drilled down almost two miles to extract 2.8-km of ice core, reaching the actual bedrock beneath the Antarctic ice sheet.

The air bubbles trapped inside the ice are “like tiny time capsules of Earth’s atmospheric past”. The samples equate to a continuous record of climate history dating back to 1.2 million years ago, which could illuminate the mysteries of glacial climate cycles.

This was the fourth Antarctic field mission for the Europeans behind the ‘Beyond EPICA – Oldest Ice’ project, funded by the European Commission.

They achieved more than 200 days of successful drilling and ice core processing operations across four seasons in the harsh environment of the central Antarctic plateau, working at an altitude of 3,200 meters above sea level with an average summer temperature of -35°C.

The ice core from Beyond EPICA will offer unprecedented insights into the Mid-Pleistocene Transition, a remarkable period between 900,000 and 1.2 million years ago when glacial cycles slowed down from 41,000-years to 100,000-year intervals.

The reasons behind this shift remain one of climate science’s enduring mysteries, one which this project seeks to unravel.

Collecting and classifying ice core samples in Antarctic – PNRA / IPEV via SWNS

“We have marked a historic moment for climate and environmental science,” said Carlo Barbante, Coordinator of Beyond EPICA and professor at Ca’ Foscari University of Venice, a member of the Institute of Polar Sciences of the National Research Council of Italy (Cnr-Isp).

“This is the longest continuous record of our past climate from an ice core, and it can reveal the interlink between the carbon cycle and temperature of our planet.”The team speculated that even older ice—dating back 2.58 million years ago—may be discovered within the core’s base. Scientists Drill Ice Core–2 Miles Down–Extracting 1.2 Million Years of Climate Record On Earth

Read More........→February 07, 2025

First major chunk breaks off world's biggest iceberg

PARIS - An enormous chunk has broken off the world's largest iceberg, in a possible first sign the behemoth from Antarctica could be crumbling.

The colossal iceberg -- which is more than twice the size of Greater London and weighs nearly one trillion tonnes -- had largely stayed intact since it started slowly moving north in 2020.

It has been drifting toward the remote island of South Georgia in the South Atlantic, raising the prospect it could run aground in shallower water and disrupt feeding for baby penguins and seals.

But a chunk about 19 kilometres (12 miles) long has cleaved off, said Andrew Meijers from the British Antarctic Survey, who encountered the iceberg in late 2023 and has tracked its fate via satellite ever since.

"This is definitely the first significant clear slice of the iceberg that's appeared," the physical oceanographer told AFP.

Soledad Tiranti, a glaciologist currently on an Argentinian exploration voyage in the Antarctic, also told AFP that a section had "broken" away.

The jagged piece has an area of roughly 80 square kilometres (31 square miles) -- huge in its own right, but just a fraction of the approximately 3360 square kilometres that remained.

Meijers said icebergs were full of deep fractures, and although this monumental specimen had shrunk over time and lost a much smaller piece, it had "held together pretty nicely".

"This is a sign that those rifts in it are starting to break up," he said.

In the past, other mega-icebergs had fallen apart "relatively quickly over the course of several weeks" once they started losing big pieces, he said.

It was hard to say if this was "a loose tooth just waiting to come out" or evidence of a much bigger change underway.

"I'm sorry to say but it's not really an exact science how these things fall apart... it's really hard to say if this is going to blow apart now, or it's going to hang together for longer," Meijers said.

Known as A23a, the world's biggest and oldest iceberg calved from the Antarctic shelf in 1986.

It remained stuck for over 30 years before finally breaking free in 2020, its lumbering journey north sometimes delayed by ocean forces that kept it spinning in place.

This monster block of freshwater was being whisked along by the world's most powerful ocean "jet stream" -- the Antarctic Circumpolar Current.

Meijers said its trajectory toward South Georgia, a crucial feeding ground for seals and penguins, would unlikely change because it had lost this chunk.

But should it collapse further it would pose "much less of a threat for wildlife" because foraging animals could manoeuvre unimpeded between the smaller chunks to find food, he added.

Icebergs had grounded there in the past and caused significant mortality to penguin chicks and seal pups.Tiranti said the iceberg was expected to keep plodding its way north but its exact course depended greatly on how local currents influenced its movements. First major chunk breaks off world's biggest iceberg

Read More........→February 06, 2025

Scale of microplastics in Antarctic revealed in preliminary survey results

(Image: IAEA)

The first results of the pioneering scientific research project launched earlier this year have catalogued microplastic particles in the sea water, sediment and animals in Antarctica.

The preliminary results were outlined during an International Atomic Energy Agency (IAEA) General Conference session focusing on the study, which is supported by Argentina and forms part of the wider IAEA NUTEC plastics initiative, which aims to use nuclear technologies to tackle plastic pollution.

Nathalie Bernard, from the IAEA Marine Environment Laboratories and University of Buenos Aires, unveiling the results, said that "sadly we have found microplastics everywhere, on every sample, every matrix". She said that the concentrations of microplastics varied by location and by day.

More than 250 samples were collected from the Almirante Irizer icebreaker, which sailed 27,209 kilometres over 125 days covering 84 sampling stations. Over the course of a week 166 samples were collected from Argentina's Carlini research station base as part of what was described as the first study of microplastics pollution from South America to Antarctica.

The samples were of water, of sediment and also of penguin droppings and shellfish. Bernard said: "All of these results were possible thanks to nuclear techniques, specifically vibrational microspectroscopy which allows us not only to count, but also identify polymers. We were able to analyse particles as small as 20 microns (WNN note: for comparison a human hair is about 100 microns) and this is important because we found out that almost 90% of the particles we analysed were smaller than 100 microns and ... most of the studies conducted before have focused on larger particles, larger than 300 microns, which clearly overlooks the larger majority."

The preliminary results - with 30% of the samples analysed so far, found that in terms of distribution in water, in Buenos Aires it was 256 microplastic particles per litre, compared with 5 microplastics particles per litre in the Antarctic Ocean and 21 microplastics particles per litre at Carlini Station in the Antarctic.

The Carlini samples found 6000-15,000 microplastic particles per kilogramme of sediment, 15 microplastic particles per square metre of sand and 200-4000 microplastic particles per biological sample of shellfish or penguin droppings.

The prevalence and type of microplastics was shown to the session (Image: WNN photo/IAEA/Bernard slide)

There were 11 different types of plastics found in the samples, 62% were "Teflon-like microplastics" and 29% were polyethylene-like. Examples of the types of products using the types of plastics found included frying pans, PVC pipes and plastic drinks bottles.

The early theories about the possible sources of the pollution in Antarctica include fisheries, local human activities and global sources, via the atmosphere or ocean currents.

Bernard said that the conclusions of the preliminary study was that "we know now that microplastics are everywhere, that we can find different levels and types between the sites and that the levels in Antarctica are relatively low if we compare them with highly populated industrial zones - but they are far away from zero, which is what it was thought to be until recently in Antarctica.".

The next steps are to finalise the analysis and do extra checks before sharing the results globally and using the figures as a baseline for future surveys, to assess possible pollution sources and inform policy makers for local and global actions in line with the Antarctic Treaty.

The meeting also heard progress reports on the United Nations actions to end plastics pollution and how the NUTEC initiative can help with plastics upcycling using irradiation to allow plastic waste to not just be traditionally recycled, but also used in cement or in wood/plastic composits - one of the examples given was Argentina using radiation-modified railway sleepers from plastic waste.

Argentina's Foreign Affairs Minister Diana Mondino said that the country was one of the original signatories of the Antarctic Treaty and said: "There's growing concern in understanding the impact in the Antarctic ecosystem from plastics and microplastics." She said the results had prompted the creation of a regional group in Latin America led by Argentina to focus on the issue.

IAEA Director General Rafael Mariano Grossi said the NUTEC initiative had been well received because "we do have a serious problem with microplastics, nanoplastics and we did also have a scarcity of information, objective information". He said having the facts was important so people can take "informed decisions when it comes to the protection of this environment, which is so pristine and that we all care for".

"This is not a simple environmental endeavour that we take for the sake of knowing a little bit more - the idea is that we provide important information that is relevant for fisheries, relevant for very important economic activities in all our countries."

Australia's ambassador Ian Biggs said that Australia had a major stake in the international effort in Antarctica and he said that according to projections there could soon be a tonne of plastic in the ocean for every three tonnes of fish, saying this showed the necessity of action to tackle plastic pollution and he said Australia believed that the NUTEC programme was "making a real difference in helping countries address pressing global challenges on plastic pollution".

More than 400 samples were taken during the study (Image: Still from IAEA video)

The background

The IAEA's NUTEC plastics scheme was established in 2020 and uses a series of monitoring laboratories to use nuclear technology to sample and analyse microplastics - which are bits of plastic less than 5 millimetres in diameter - in the environment. There are more than 60 countries participating in monitoring of microplastics in the sea, and the goal is to equip more than 50 laboratories with the technology to form a global monitoring network.

The aim is to then be able to take action to bring in measures designed to reduce the sources of the pollution - at least 30 countries are involved in developing innovative recycling technology, including using irradiation to treat plastics and make them fit for reuse, or for a wider range of reuses. This process uses gamma and electron beam radiation technologies to modify certain types of plastic waste, breaking down plastic polymers judged not to be of sufficient quality into smaller components and then allowing them to be used to generate new plastic products.

The IAEA cites studies suggesting that only around 10% of plastic produced between 1950 and 2015 has been recycled, with the majority (about 60%) going to landfill, meaning action is imperative given estimates that there will be one tonne of plastic for every three tonnes of fish within a few years.

Grossi visited an IAEA mission in Antarctica in January with Argentina's president to see the start of work for the project, with the IAEA explaining that "there is still almost no information available on where and how much microplastics arrive in the Antarctic and how much is taken up by Antarctic organisms. There is also very little data existing on the types of microplastics reaching this pristine area through ocean currents, atmospheric deposition and the presence of humans in the Antarctic".It also said the "presence of microplastics can contribute to accelerating the ice-loss in Antarctica by reducing ice reflectivity, altering surface roughness, promoting microbial activity, acting as thermal insulators, and contributing to mechanical weakening of the ice structure". Scale of microplastics in Antarctic revealed in preliminary survey results

Read More........→January 10, 2025

First Antarctic amber discovery sheds light on ancient forests

Berlin, (IANS): Scientists in Germany have discovered amber in Antarctica for the first time, revealing that around 90 million years ago, the continent's climate conditions supported resin-producing forests, Germany's Alfred Wegener Institute (AWI) reported.

This southernmost discovery of amber offers new insights into Cretaceous forests near the South Pole, AWI said in a press release.

The amber was discovered in a sediment core retrieved from the Amundsen Sea at a depth of 946 meters, using a seabed drilling device during a 2017 expedition aboard the icebreaker Polarstern. For analysis, the source material was carefully air-dried and sliced into pieces about 1 mm in diameter to extract the amber. Potential remnants of tree bark were also identified, offering further clues about the ancient forests near the South Pole.

"The analyzed amber fragments provide direct insights into the environmental conditions that prevailed in West Antarctica 90 million years ago," AWI marine geologist Johann P. Klages said. "It was very exciting to realize that, at some point in their history, all seven continents had climates that allowed resin-producing trees to survive."The research team, led by scientists from AWI and the TU Bergakademie Freiberg, has published their findings in the journal Antarctic Science, Xinhua news agency reported. First Antarctic amber discovery sheds light on ancient forests | MorungExpress | morungexpress.com

Read More........→November 14, 2024

Scale of microplastics in Antarctic revealed in preliminary survey results

The first results of the pioneering scientific research project launched earlier this year have catalogued microplastic particles in the sea water, sediment and animals in Antarctica. (Image: IAEA)

By Alex Hunt: The preliminary results were outlined during an International Atomic Energy Agency (IAEA) General Conference session focusing on the study, which is supported by Argentina and forms part of the wider IAEA NUTEC plastics initiative, which aims to use nuclear technologies to tackle plastic pollution.

Nathalie Bernard, from the IAEA Marine Environment Laboratories and University of Buenos Aires, unveiling the results, said that "sadly we have found microplastics everywhere, on every sample, every matrix". She said that the concentrations of microplastics varied by location and by day.

More than 250 samples were collected from the Almirante Irizer icebreaker, which sailed 27,209 kilometres over 125 days covering 84 sampling stations. Over the course of a week 166 samples were collected from Argentina's Carlini research station base as part of what was described as the first study of microplastics pollution from South America to Antarctica.

The samples were of water, of sediment and also of penguin droppings and shellfish. Bernard said: "All of these results were possible thanks to nuclear techniques, specifically vibrational microspectroscopy which allows us not only to count, but also identify polymers. We were able to analyse particles as small as 20 microns (WNN note: for comparison a human hair is about 100 microns) and this is important because we found out that almost 90% of the particles we analysed were smaller than 100 microns and ... most of the studies conducted before have focused on larger particles, larger than 300 microns, which clearly overlooks the larger majority."

The preliminary results - with 30% of the samples analysed so far, found that in terms of distribution in water, in Buenos Aires it was 256 microplastic particles per litre, compared with 5 microplastics particles per litre in the Antarctic Ocean and 21 microplastics particles per litre at Carlini Station in the Antarctic.

The Carlini samples found 6000-15,000 microplastic particles per kilogramme of sediment, 15 microplastic particles per square metre of sand and 200-4000 microplastic particles per biological sample of shellfish or penguin droppings.

The prevalence and type of microplastics was shown to the session (Image: WNN photo/IAEA/Bernard slide)

There were 11 different types of plastics found in the samples, 62% were "Teflon-like microplastics" and 29% were polyethylene-like. Examples of the types of products using the types of plastics found included frying pans, PVC pipes and plastic drinks bottles.

The early theories about the possible sources of the pollution in Antarctica include fisheries, local human activities and global sources, via the atmosphere or ocean currents.

Bernard said that the conclusions of the preliminary study was that "we know now that microplastics are everywhere, that we can find different levels and types between the sites and that the levels in Antarctica are relatively low if we compare them with highly populated industrial zones - but they are far away from zero, which is what it was thought to be until recently in Antarctica.".

The next steps are to finalise the analysis and do extra checks before sharing the results globally and using the figures as a baseline for future surveys, to assess possible pollution sources and inform policy makers for local and global actions in line with the Antarctic Treaty.

The meeting also heard progress reports on the United Nations actions to end plastics pollution and how the NUTEC initiative can help with plastics upcycling using irradiation to allow plastic waste to not just be traditionally recycled, but also used in cement or in wood/plastic composits - one of the examples given was Argentina using radiation-modified railway sleepers from plastic waste.

Argentina's Foreign Affairs Minister Diana Mondino said that the country was one of the original signatories of the Antarctic Treaty and said: "There's growing concern in understanding the impact in the Antarctic ecosystem from plastics and microplastics." She said the results had prompted the creation of a regional group in Latin America led by Argentina to focus on the issue.

IAEA Director General Rafael Mariano Grossi said the NUTEC initiative had been well received because "we do have a serious problem with microplastics, nanoplastics and we did also have a scarcity of information, objective information". He said having the facts was important so people can take "informed decisions when it comes to the protection of this environment, which is so pristine and that we all care for".

"This is not a simple environmental endeavour that we take for the sake of knowing a little bit more - the idea is that we provide important information that is relevant for fisheries, relevant for very important economic activities in all our countries."

Australia's ambassador Ian Biggs said that Australia had a major stake in the international effort in Antarctica and he said that according to projections there could soon be a tonne of plastic in the ocean for every three tonnes of fish, saying this showed the necessity of action to tackle plastic pollution and he said Australia believed that the NUTEC programme was "making a real difference in helping countries address pressing global challenges on plastic pollution".

More than 400 samples were taken during the study (Image: Still from IAEA video)

The background

The IAEA's NUTEC plastics scheme was established in 2020 and uses a series of monitoring laboratories to use nuclear technology to sample and analyse microplastics - which are bits of plastic less than 5 millimetres in diameter - in the environment. There are more than 60 countries participating in monitoring of microplastics in the sea, and the goal is to equip more than 50 laboratories with the technology to form a global monitoring network.

The aim is to then be able to take action to bring in measures designed to reduce the sources of the pollution - at least 30 countries are involved in developing innovative recycling technology, including using irradiation to treat plastics and make them fit for reuse, or for a wider range of reuses. This process uses gamma and electron beam radiation technologies to modify certain types of plastic waste, breaking down plastic polymers judged not to be of sufficient quality into smaller components and then allowing them to be used to generate new plastic products.

The IAEA cites studies suggesting that only around 10% of plastic produced between 1950 and 2015 has been recycled, with the majority (about 60%) going to landfill, meaning action is imperative given estimates that there will be one tonne of plastic for every three tonnes of fish within a few years.

Grossi visited an IAEA mission in Antarctica in January with Argentina's president to see the start of work for the project, with the IAEA explaining that "there is still almost no information available on where and how much microplastics arrive in the Antarctic and how much is taken up by Antarctic organisms. There is also very little data existing on the types of microplastics reaching this pristine area through ocean currents, atmospheric deposition and the presence of humans in the Antarctic".It also said the "presence of microplastics can contribute to accelerating the ice-loss in Antarctica by reducing ice reflectivity, altering surface roughness, promoting microbial activity, acting as thermal insulators, and contributing to mechanical weakening of the ice structure". Scale of microplastics in Antarctic revealed in preliminary survey results

Read More........→September 20, 2024

Antarctica’s hidden threat: meltwater under the ice sheet amplifies sea-level rise

Chen Zhao, University of Tasmania and Ben Galton-Fenzi, Australian Antarctic Division

One of the biggest challenges in predicting Antarctica’s deeply uncertain future is understanding exactly what’s driving its ice loss.

A vast network of lakes and streams lies beneath the thick ice sheet. This water can lubricate the ice, allowing it to slide more rapidly toward the ocean.

Our new research shows “subglacial water” plays a far larger role in Antarctic ice loss than previously thought. If it’s not properly accounted for, future sea-level rise may be vastly underestimated.

Including the effects of evolving subglacial water in ice sheet models can triple the amount of ice flowing to the ocean. This adds more than two metres to global sea levels by 2300, with potentially enormous consequences for coastal communities worldwide.

How hidden lakes threaten Antarctic Ice Sheet stability. (European Space Agency)

Understanding the role of subglacial water

Subglacial water forms when the base of the ice sheet melts. This occurs either due to friction from the movement of the ice, or geothermal heat from the bedrock below.

The presence of subglacial water enables ice to slide over the bedrock more easily. It can also cause further melting under ice shelves, leading to even faster ice loss.

So it’s crucial to understand how much subglacial water is generated and where it goes, as well as its effect on ice flow and further melting.

But subglacial water is largely invisible. Being hidden underneath an ice sheet more than two kilometres deep makes it incredibly difficult to observe.

Scientists can drill boreholes through hundreds to thousands of metres of ice to get to it. But that’s an expensive and logistically challenging process.

Alternatively, they can use ice-penetrating radar to “see” through the ice. Another technique called laser altimetry examines changes in the height of the ice at the surface. Bulges might appear when lakes under the ice sheet fill, or disappear when they empty.

More than 140 active subglacial lakes have been identified beneath Antarctica over the past two decades. These discoveries provide valuable insights. But vast regions — especially in East Antarctica — remain unexplored. Little is known about the connections between these lakes.

What we did and what we found

We used computer simulations to predict the influence of subglacial water on ice sheet behaviour.

We used two computer models:

• an advanced ice sheet model that simulates how the ice sheet flows and responds to climate.
• a specialised hydrology model that predicts subglacial water production and flow.

Then we explored how different assumptions about subglacial water pressure affect ice sheet dynamics. Specifically, we compared scenarios where water pressure was allowed to change over time against scenarios where it remained constant.

When the effects of changing subglacial water pressure were included in the model, the amount of ice flowing into the ocean under future climate nearly tripled.

These findings suggest many existing sea-level rise projections may be too low, because they do not fully account for the dynamic influence of subglacial water.

Our research highlights the urgent need to incorporate subglacial water dynamics into these models. Otherwise we risk significantly underestimating the rate and magnitude of future sea-level rise.

In the video below, the moving dark lines show where grounded ice begins to float. The left panel is a scenario where subglacial water is not included in the ice sheet model and the right panel is a scenario that includes the effects of evolving subglacial water.

Simulated Antarctic ice velocity over 1995–2300, using the Elmer/Ice model of ice sheets.

A looming threat

Failing to account for subglacial water means global sea-level rise projections are underestimated by up to two metres by 2300.

A two-metre rise would put many coastal cities in extreme danger and potentially displace millions of people. The economic damage could reach trillions of dollars, damaging vital infrastructure and reshaping coastlines worldwide.

It also means the timing of future tipping points are underestimated too. This is the point at which the ice sheet mass loss becomes much more rapid and likely irreversible. In our study, most regions cross this threshold much earlier, some as soon as 2050. This is deeply concerning.

The way forward

Understanding Antarctica’s hidden water system is challenging. The potential for rapid, catastrophic and irreversible ice loss remains.

More observations are needed to improve our models, particularly from remote regions such as East Antarctica. Continuing to gather information from boreholes, ice-penetrating radar and satellites will help us better understand how the underside of the ice sheet behaves. These techniques can then be combined with computer simulations to enable more accurate projections of future ice loss and sea-level rise.

Our new research shows integrating subglacial water dynamics into ice sheet models is a top priority. Understanding this hidden threat is crucial as the world grapples with the consequences of global warming especially rising seas.

Chen Zhao, ARC DECRA Senior Research Fellow, Institute for Marine and Antarctic Studies, University of Tasmania and Ben Galton-Fenzi, Principal Scientist, Australian Antarctic Division

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

Read More........→June 05, 2024