Latest news with #BritishAntarcticSurvey
The Guardian
a day ago
- Science
- The Guardian
‘It looks more likely with each day we burn fossil fuels': polar scientist on Antarctic tipping points
For more than 20 years, Louise Sime has worked at the British Antarctic Survey specialising in polar climate dynamics. She uses ice cores to reconstruct past conditions and predict future changes. She now leads several international Earth modelling projects. Why are the Arctic and Antarctic regions important for the rest of the world?They are one of the pillars of global climate stability, a giant store of frozen water, an essential 'biotic pump' that helps to store carbon, and an albedo shield that reflects much of the sun's light and heat back out to space. When and why did scientists become concerned about tipping points in Antarctica?It has become a major talking point in the past five to 10 years, though the possibility has been known for much longer. Up until 2016, the sea ice in Antarctica seemed relatively stable. Then everything started to change. At first, the decline was mostly in line with climate models. But suddenly, in 2023, there was an enormous drop. About 2.5 million sq km of Antarctic sea ice went missing relative to the average before 2023. The anomaly was of such a magnitude that it's quite hard for scientists to know what to make of it. It has been described as a five sigma event. What is a five sigma event?Something that may only happen once in 10,000 years, or higher, possibly once in several million years. It was so far outside of expectations that the statistics became really hard to handle. It was very startling. What was the cause? It's still not absolutely clear but it is probably associated with global warming and circulation changes in the oceans. In that year, there was an enormous atmospheric river event over East Antarctica, which was also a five sigma event. This coincided with the biggest heatwave on record, where we had a temperature anomaly in excess of 40C. What effect did this have on the region?When that much sea ice is lost, there are substantial knock-on impacts. While the ocean is covered by ice, the temperature above the surface can easily be -20C, -30C. But as soon as the water is exposed, then the surface temperature cannot go below -2C. And once the surface is opened to the atmosphere, then you start to get evaporation of water vapour. That means a sudden and substantial change of weather around Antarctica. What are the potential tipping points in the polar regions?Tipping points are broadly defined as abrupt changes that are irreversible, at least on human timescales. We know they are possible in polar ecosystems based on ice-core records going back 800,000 years. We are less sure where those tipping points are. That is because these regions are shaped by complex interactions. It also depends what scale we are talking about. Small, local tipping points may have already been passed on particular ice sheets or coastal ice shelves or possibly even sea ice. But it is less certain that the entire region is near a tipping point. What are ice sheets and why do they matter?Ice must cover at least 50,000 sq km of land to qualify as an ice sheet, also known as a continental glacier. They grow when there is more snow than melt-off, and shrink when there is more melt-off than snow or if they slide into the sea. We know this is a risk in Antarctica, because it's got a backward sloping bedrock. If the ice there is thinned, then at some point it starts floating in deep basins and begins melting from below. Then you would have a sort of catastrophic collapse. How do they differ from ice shelves?Ice shelves are floating tongues of ice that flow out from land glaciers over a cold coastal ocean. They range in thickness from 50 to 600 metres, and help to buttress land ice. We've seen examples where they catastrophically collapse because melt water accumulates over the surface and forces cracks into the shelves. An ice shelf that may have been there for hundreds or thousands of years can collapse within months, possibly even weeks. By themselves, the collapse of ice shelves doesn't add much to global sea-level rise, but it can remove the buttress on much bigger ice sheets, which can then slide faster into the ocean. West Antarctica appears to be the area of greatest concern. Why?This is the location of two huge and vulnerable glaciers: Pine Island and Thwaites. We know that their buttressing gate glaciers on the shore are thinning and retreating. That allows more of the ice sheet to flow into the ocean. Satellite images show this has been going on for some time and has accelerated at least since the year 2000. All of those glaciers are connected together so if they slipped into the ocean that would add about four metres to global ocean levels. But the key question is how long this will take. Looking at past records of change in Antarctica, it's likely to take hundreds of years. But a very large acceleration would be felt almost immediately and it would result in the global sea level going up much, much faster in the near future. How does this compare with the situation in the Arctic?The potential for Antarctica to increase global sea levels is scarier than for Greenland. Right now, they're both contributing similar amounts to sea-level rise, but in future, it could be Greenland goes up a bit and then Antarctica goes up catastrophically. Greenland has the potential to raise sea levels by five or six metres, but we don't expect this will come in the form of an absolutely catastrophic, abrupt loss. Most of the ice in Greenland is not below sea level so we can see what is happening and we expect it will melt in a linear fashion. By contrast, Antarctica has 80 metres of potential sea-level rise. We don't expect all of that, but it is harder to know exactly what is happening. Much of Antarctica is below sea level and affected by the ocean, which means it is less stable and harder to observe. We also know there are parts of Antarctica where warm water is encroaching on to unstable shelves and we know that ice could retreat in some of the sloping basins – for example in East Antarctica and Wilkes Land. We don't know where that tipping point is, but if we hit it, there will be an irreversible retreat of the West Antarctic sheet. How long may that take?It's safer to assume that parts of it could happen rapidly. We know that ice shelves can collapse in a matter of weeks or months. On a bigger scale, evidence from the past suggests West Antarctica is unlikely to catastrophically lose all its ice in tens of years. It could unfold over hundreds or even thousands of years, but once you cross the tipping point and initiate that process, it is possible that we'd immediately see a substantial acceleration and jumps in sea level. We need more study. Is it possible that this is already under way?Yes. Some studies have suggested we may have passed tipping points, so the loss of the West Antarctic ice sheet may now be inevitable because of the warming of the oceans. However, this is far from clear. Tipping points definitely exist and we may already have passed some of the minor ones, but there's also a good chance, in my view, that we haven't yet crossed the major ones in Antarctica. What would happen elsewhere if the Antarctic breaches these tipping points?A huge proportion of the global population lives very close to the sea level so if the oceans rise by several metres, I find it personally quite hard to think about the consequences. They would be devastating. How would it affect the climate?A huge amount of the carbon dioxide that is emitted today is being sequestered in the Southern Ocean. But that only happens if ecosystems work effectively as a biological pump that draws carbon dioxide into the depths via plankton, krill and other species. If we cross tipping points in Antarctica, it would undermine that ecosystem. That would change the trajectory of how much carbon dioxide remains in the atmosphere in the coming years, and likely increase global temperature, which will be felt by everyone. What is your gut feeling about whether we have crossed a tipping point in the Antarctic? It's unthinkable, but it's not impossible, and it looks more likely with each day that we continue burning fossil fuels. It's beyond worrying. What difference would it make if we stopped burning oil, gas, coal and trees? If we stop emitting carbon tomorrow, then it's quite likely that we would see no further decreases in Arctic sea ice. And it's quite likely that other parts of the global climate system would immediately stabilise and temperatures would stop going up. So even if we had passed some tipping points, it's very likely that we would not pass any others. Is there any way to reverse what's going on with a technological fix?Studies suggest geoengineering is speculative and could make things worse. I'm personally not against what-if modelling experiments: if we did have giant space mirrors, what would the climate of Earth look like at that point? But it's unlikely in my personal view that any of them actually would be usable. They shouldn't distract us from our primary goal which is to stop the burning of any fossil fuel as quickly as possible. How do you feel about the risk of a tipping point in the Antarctic?As a human being, I have so much trouble trying to think about the magnitude of the sea-level rise, that I'm not sure I have the capacity to really think it through. I really enjoy working on polar science generally. It's a privilege, but I don't really have a good answer for you. We scientists just do our best to encourage everyone to decarbonise, please, for my kids' future, as well as for everyone else's kids. Tipping points – in the Amazon, Antarctic, coral reefs and more – could cause fundamental parts of the Earth system to change dramatically, irreversibly and with devastating effects. In this series, we ask the experts about the latest science – and how it makes them feel. Tomorrow, Tim Lenton talks about positive social tipping points Read more
CBS News
a day ago
- Science
- CBS News
New report indicates emperor penguins are living on thin ice
Emperor penguins live in some of the most remote and environmentally pristine regions in the world. But that doesn't mean they're safe from the impacts of a warming planet. Just ask Dr. Birgitte McDonald, a researcher at Moss Landing Marine Laboratories. For 15 years, she's studied emperor penguins and how they dive, swim, and forage for food. A new report published in the journal Nature has deepened her concern about the penguins' survival. "This report wasn't too surprising but a little depressing at how fast it seems to be happening in one region," remarked McDonald. The report involved scientists from the British Antarctic Survey. For 15 years, they've monitored 16 colonies of emperor penguins via satellite imagery. These colonies represent roughly a third of all the emperor penguins on earth. Emperor penguin with chicks, Aptenodytes forsteri, Snow Hill Island, Antartic Peninsula, Antarctica Getty Images A new analysis of the satellite data has detected a higher and more dramatic decline in the birds' populations. Five years ago, the scientists found a 9.5% drop. The updated data shows a startling 22% drop. "Overall, the picture is quite poor. It's quite dire for the penguins," remarked Dr. Peter Fretwell, lead author of the new analysis. The warming of the planet is thinning and destabilizing the sea ice that is critical for the breeding and molting of the penguins. There is more competition for available food among all the creatures in the area. In addition, scientists are detecting more extreme weather in the form of more rainfall and storms. An increase in extreme weather is a hallmark of climate change. "The chicks are well insulated with their down, but the down only really works if they stay dry. And so, if there is a lot more rain, the chicks will have to spend more energy trying to stay warm," explained McDonald. "So, going out to sea for the first time at a lighter weight, and that could decrease their chance of survival." As to what we can do to slow the warming, McDonald offered some advice: fly less, try more carpooling and driving less, and eat less meat. These are all small steps, but if large enough people practice them, McDonald noted, there could be a difference. Here are more ideas on how you can reduce your carbon footprint. The Associated Press contributed to this report.
Yahoo
3 days ago
- Science
- Yahoo
Scientists make concerning discovery at 'Doomsday Glacier' in Antarctica: 'Usually made stronger by passing storms'
Scientists have discovered another cause for melting glaciers, and it's one that has been overlooked before. According to fast-moving winds in West Antarctica frequently blow over the Amundsen Sea; they're called low-level jets. A study by the Indian Institute of Technology and the British Antarctic Survey revealed "that the effects of low-level jets could be pivotal in shaping the future of the Thwaites and Pine Island glaciers. These are two of the fastest melting ice bodies on the planet." The Thwaites Glacier, in particular, is so concerning that it has been nicknamed the Doomsday Glacier. In 2014, scientists attached 22 sensor instruments to weather balloons and launched them near the coast. "We wanted to understand how often these LLJs happen and what causes them," lead author Sai Prabala Swetha Chittella said, per "These processes could potentially influence the rate at which Thwaites and Pine Island glaciers melt, and thus their contribution to sea-level rise." The data showed 11 LLJs. The researchers used a weather simulation tool to replicate eight of them. One of them was formed by dense, cold air that moves downhill. Six were caused when these winds were intensified by cyclones over the Bellingshausen Sea. "The most important thing we found is that LLJs happen often in this part of Antarctica and are usually made stronger by passing storms," co-author Andrew Orr of the British Antarctic Survey said, according to Researchers worry that LLJs could shift sea ice, allowing warmer water to be transferred under the ice and causing it to melt. Another phenomenon happening in West Antarctica is ice piracy, where one melting glacier steals ice from another. These reports of melting ice are a huge problem. For example, scientists warn that about 15 million people are at risk of severe flooding from glacial lake swells and bursts. Do you worry about air pollution in and around your home? Yes — always Yes — often Yes — sometimes No — never Click your choice to see results and speak your mind. While extreme weather events have always existed, the human-caused climate crisis has supercharged them, making them more frequent and more dangerous to communities and the environment. The ice loss is also transforming coastlines, threatening homes, and disrupting food sources. Additionally, coastal cities are at risk of flooding because of the melting of ice sheets. "We plan to continue our investigation of these extreme winds over this region of West Antarctica, including focusing on winter, when they are likely to be even stronger and more frequent," co-author Pranab Deb said, per Melting glaciers are a complex problem, which is why it's vital to explore critical climate issues to better understand how to handle them. Ultimately, environmentally harmful human activities — namely, burning dirty fuels — need to be reduced to help curb rising global temperatures. Switching to an electric vehicle, turning to native plants, and using clean energy can all help lead us to a brighter, safer future. Join our free newsletter for good news and useful tips, and don't miss this cool list of easy ways to help yourself while helping the planet.
Daily Maverick
4 days ago
- Politics
- Daily Maverick
Top Antarctic meeting kicks off behind ‘Ice Curtain' as transparency goes up in flames
Antarctica's fate is debated in secrecy behind closed doors and confusion in Milan. The world's premier meeting on the governance of Earth's most threatened continent — representing 10% of the planet — opened today in Milan behind closed doors. The 47th Antarctic Treaty Consultative Meeting (ATCM) involves 29 consultative states — including the US, China, Russia and South Africa — which gather annually to deliberate the future of the frozen, but melting, wilderness. There are also 29 observer states with no decision-making powers. During the course of the next week and a half, the decision-maker states will debate a range of governance matters relating to the Antarctic as part of a 1959 treaty which is devoted to peaceful activities like science and tourism. Under the treaty's environmental constitution, the Madrid Protocol, mining is banned. The live substance of the meeting, seen as diplomatically sensitive, has always been held behind closed doors. According to some sources, only 30 minutes of the 150-minute opening plenary of the ATCM on Tuesday morning were public. However, according to the meeting rules, the entire 'opening plenary session shall be held in public, other sessions shall be held in private, unless the Meeting shall determine otherwise'. No decisions have been published on the committee's website to indicate why the opening plenary was closed or partially closed. The meeting is hosted in alphabetical order by a different consultative state every year. This year hosted under a far-right coalition government led by Giorgia Meloni and her party, Brothers of Italy, the meeting's organising committee has yet to respond to Daily Maverick's repeated questions about how to access the now-concluded opening plenary — first sent in August 2024. And yet the British Antarctic Survey this month released science showing that it's not just South Pole transparency that seems to be going up in flames. According to the scientific agency, the population of emperor penguins — whose protection China and Russia have blocked at the consultative meeting in recent years — has declined 22% over the 15 years to 2024. The reported plunge in numbers of these iconic flightless ambassadors relates to a 'key sector of the continent' of the West Antarctic. 'This compares with an earlier estimate — 2009 and 2018 — of a 9.5% reduction across Antarctica as a whole,' the agency reports. In another study released this week, the agency reveals that Signy Island seal populations have sharply declined by about 50% over 50 years — a trend that is 'strongly linked to shifts in sea ice; when it forms and melts each year, and how long it lasts'. Next year, the meeting will be hosted by Japan. A prominent Japanese polar academic, Kobe University's Professor Akiho Shibata, is in Milan this week and reported on his Facebook page that multiple delegates were kicked out of the treaty's environmental protection committee session on Monday. 'A confusion at the beginning with just too small a room (Brown Hall) with too few chairs; those standing, including me, were ordered to leave the room for security reasons!' exclaimed Shibata, an Antarctic law expert. In a twist that would be farcical if the ecological and geopolitical stakes were not so high, Shibata added: 'Because of that, I could not observe an important discussion on 'Enhancing the Transparency in the ATCM and CEP [Committee for Environmental Protection] proposed by the Netherlands, Australia and Korea — more media access to the meetings; more proactive public outreach; and possible increase of experts).' Shibata, an accredited delegate, wrote earlier this week: 'Very difficult to find the way in, with a lot of construction going on.' He advised: 'Have extra time to come on Monday for CEP and Tuesday for plenary.' The meeting has been criticised by other experts for its 'Ice Curtain' approach — a phrase coined by Tasmania-based polar author and journalist Andrew Darby. Unlike the high-profile UN Ocean Conference held in Nice, France, earlier this month, the Antarctic meeting was not broadly advertised. The Antarctic Treaty is not part of the UN. When asked, South African official Ashley Johnson promptly replied to our queries, but seemed as mystified as the press. For streaming details of the opening plenary, Johnson suggested that we contact the organising committee, which has not responded to our questions. Despite being sent multiple unaddressed emails requesting information on media access to the public session, organising committee official Orazio Guanciale last month claimed that Italy was 'still waiting for … say … receiving the interest of members of the press to participate in the public session of Tuesday, 24 June'. 'Of course we are open to facilitate to the maximum extent possible the participation of the press and … say … the broadcasting of the public session.' He noted: 'The issue of transparency is really very, very important … say … the Antarctic Treaty embodies the principle of transparency… ' Per tradition, the documents discussed at the meeting are to be unlocked on the secretariat archive directly after the talks on 3 June — however, the actual live minutes will only be released after scrutiny by the consultative states some months later. 'Closed discussions can be useful for facilitating open discussion and exchange of ideas. However, this has to be balanced with the need for transparency and accountability,' Claire Christian, executive director of the Antarctic and Southern Ocean Coalition, a network of NGOs, told Daily Maverick. 'Other international organisations have implemented various practices to promote transparency without compromising their effectiveness or ability to have productive discussions. As an example, papers for the meeting could be made publicly available ahead of the meeting so that the public could better understand the issues that are being discussed.' DM
Daily Mail
7 days ago
- Science
- Daily Mail
King Charles pays tribute to 'resilience' of antarctic research scientists
The king has recorded a personal message for Antarctic researchers as the southern hemisphere marks the shortest day of the year. While the UK enjoys its longest day of sunlight on Saturday, British scientists at the South Pole experience 24 hours of darkness. In a morale-raising message recorded for the BBC World Service's midwinter broadcast, Charles praised the researchers' 'critically important' work as well as their 'resilience and commitment' to their jobs. 'With the sun shying away from your horizon today, I particularly wanted to send my warmest good wishes to all of those serving at British Antarctic research stations this midwinter's say and, above all, to express the greatest admiration for the critically important work you do.' He then went onto talk a little about the researchers' work. The king continued: 'The scientific research that the British Antarctic Survey undertakes, alongside teams from across the world, is today more vital than ever, telling us stories of the past, the present and possible futures. 'Each observation, measurement and calculation you undertake adds to the world's understanding of the Earth's fragile systems and the role humanity plays, as we struggle to live in harmony with nature. 'I very much appreciate the resilience and commitment to duty you all demonstrate so effectively, and which embody the pioneering spirit that has characterised British polar exploration for generations. 'On the 70th anniversary of this midwinter broadcast, I send countless special thoughts for your celebrations today.' It comes a month after the King, a longtime environmental advocate, urged people to help save the planet during a charity fundraiser. He told the crowd: 'Collaboration is far better than conflict.' The monarch said the charity's work comes at a time when efforts are under way to 'develop an even greater ability to manage the human and animal conflict'. Charles said: 'If we're going to rescue this poor planet (from) continuing degradation, and restore some degree of harmony to the proceedings, we must also understand that whatever we take and exploit from nature. 'We need to give something back in return to enable nature to sustain us.' The BBC World Service's midwinter broadcast is part of a day of celebrations for personnel at British Antarctic Survey stations. These personnel are based at at Rothera, Bird Island, and South Georgia, and they join colleagues at other international bases across the continent to mark the day. Alongside the King's message, the programme consists of music requests and messages from home to those at BAS research stations. They traditionally feast, exchange presents, and watch the classic 1982 horror film The Thing, set in the Antarctic. This year midwinter coincides with sweltering weather back on British soil. This means the UK is preparing for thunderstorms which are set to mix with continued high temperatures on Saturday. These temperatures could reach all the way up to 34C in some areas. A yellow thunderstorm weather warning covering all of northern England, from Nottingham up to above Newcastle, will come into force from 3pm and last until 4am on Sunday. The Met Office warned the most intense storms could produce 'frequent lightning, large hail and gusty winds', along with a chance of flooding. Parts of eastern England could also see temperatures peak high enough to eclipse the 32.2C seen on Thursday and become the hottest day of the year so far.
