British Antarctic Survey’s Post

February 8, 2024 - By University of Cambridge, "Researchers from the University of Cambridge and the British Antarctic Survey have uncovered the first direct evidence that the West Antarctic Ice Sheet shrunk suddenly and dramatically at the end of the Last Ice Age, around 8,000 years ago. The evidence, contained within an ice core, shows that in one location the ice sheet thinned by 450 metres — that’s more than the height of the Empire State Building — in just under 200 years. --- This is the first evidence anywhere in Antarctica for such a fast loss of ice. Scientists are worried that today’s rising temperatures might destabilize parts of the West Antarctic Ice Sheet in the future, potentially passing a tipping point and inducing a runaway collapse. The study, published (https://lnkd.in/e4nyXEas) in Nature Geoscience, sheds light on how quickly Antarctic ice could melt if temperatures continue to soar. “We now have direct evidence that this ice sheet suffered rapid ice loss in the past,” said Professor Eric Wolff, senior author of the new study from Cambridge’s Department of Earth Sciences. “This scenario isn’t something that exists only in our model predictions and it could happen again if parts of this ice sheet become unstable.” From west to east, the Antarctic ice sheets contain enough freshwater to raise global sea levels by around 57 metres. The #WestAntarctic #IceSheet is considered particularly vulnerable because much of it sits on bedrock below #sealevel. Model predictions suggest that a large part of the West Antarctic Ice Sheet could disappear in the next few centuries, causing sea levels to rise. Exactly when and how quickly the ice could be lost is, however, uncertain. One way to train ice sheet models to make better predictions is to feed them with data on ice loss from periods of warming in Earth’s history. At the peak of the Last Ice Age 20,000 years ago, Antarctic ice covered a larger area than today. As our planet thawed and temperatures slowly climbed, the West Antarctic Ice Sheet contracted to more or less its current extent “We wanted to know what happened to the West Antarctic Ice Sheet at the end of the Last Ice Age, when temperatures on Earth were rising, albeit at a slower rate than current #anthropogenicwarming,” said Dr Isobel Rowell, study co-author from the British Antarctic Survey. “Using ice cores we can go back to that time and estimate the ice sheet’s thickness and extent.” Ice cores are made up of layers of ice that formed as snow fell and was then buried and compacted into ice crystals over thousands of years. Trapped within each ice layer are bubbles of ancient air and contaminants that mixed with each year’s snowfall — providing clues as to the changing #climate and ice extent. The researchers drilled a 651-metre-long ice core from Skytrain Ice Rise in 2019. This mound of ice sits at the edge of the ice sheet, near the point where grounded ice flows into the floating Ronne Ice Shelf." Continue reading

Antarctic 'Doomsday Glacier' Melting Faster, Scientists Warn: A massive Antarctic glacier, dubbed the "Doomsday Glacier," is melting at an accelerating rate and could be approaching irreversible collapse, international researchers are reporting. The Thwaites Glacier, holding enough ice to raise global sea levels by over two feet, has seen rapid retreat in the past 30 years. Scientists from the International Thwaites Glacier Collaboration used ice-breaking ships and underwater robots to study the glacier up close since 2018. Their findings reveal warm ocean water funneling through deep cracks in the ice, causing unexpected melting patterns. While computer modeling suggests catastrophic cliff collapse is less likely than feared, researchers project Thwaites and the Antarctic Ice Sheet could disintegrate within 200 years. This collapse could ultimately lead to 10 feet of sea level rise, devastating coastal communities worldwide. Read more of this story at Slashdot.

Antarctic 'Doomsday Glacier' Melting Faster, Scientists Warn: A massive Antarctic glacier, dubbed the "Doomsday Glacier," is melting at an accelerating rate and could be approaching irreversible collapse, international researchers are reporting. The Thwaites Glacier, holding enough ice to raise global sea levels by over two feet, has seen rapid retreat in the past 30 years. Scientists from the International Thwaites Glacier Collaboration used ice-breaking ships and underwater robots to study the glacier up close since 2018. Their findings reveal warm ocean water funneling through deep cracks in the ice, causing unexpected melting patterns. While computer modeling suggests catastrophic cliff collapse is less likely than feared, researchers project Thwaites and the Antarctic Ice Sheet could disintegrate within 200 years. This collapse could ultimately lead to 10 feet of sea level rise, devastating coastal communities worldwide. Read more of this story at Slashdot.

So if the Antarctic only started to glaciate 34 Million years ago who was selling V8 muscle cars, private jets and rocket launch systems before that to keep the Earth warm ??? Whomever it was they seem to have re-emerged around 12,000 years ago at the end of the last ice age when the Earth warmed so rapidly that the land bridges between Britain and France and between Russia and Alaska disappeared due to rising sea levels?? In fact there have been 5-6 ice ages in the last 3 billion years, which means each ended due to rising temperatures. Humans have only been around for less than 1 million years and industrialised for a mere 400. https://lnkd.in/e5dkrzg6

Why repost this? After all, what can any of us do about it? We can do something about it though: 1) we can make a point of following climate news so that our descendants will be satisfied we were paying attention and did our part to change the outcome. 2) we can choose not to deny what is happening. 3) we can vote for politicians who fund #climatemitigation now and work toward a #justtransition to a more nature-centric civilization. 4) we can surround ourselves with others in community who are creatively working to imagine a more nature-centric civilization so that we find joy, fun, and creativity in the work. #GlobalClimateStrike, week 216 #SeaLevelRise #GlobalHeating #ClimateChange #ClimateEmergency #Sustainability

Climate crisis. "The Antarctic ice sheet* is melting in a new, worrying way that scientific models used to project future sea level rise have not taken into account, suggesting current projections could be significantly underestimating the problem, according to a new study. Scientists from the British Antarctic Survey found that warm ocean water is seeping beneath the ice sheet at its “grounding line” — the point at which the ice rises from the seabed and starts to float — causing accelerated melting which could lead to a tipping point, according to the report published Tuesday in the journal Nature Geoscience. A tipping point refers to the threshold at which a series of small changes accumulate to push a system beyond a point of no return. The melting works like this: relatively warm ocean water opens cavities in the ice, allowing more water to seep in, which causes more melting and larger cavities to form, and so on. A small increase in ocean temperatures can have a very big impact on the amount of melting, the study found. As climate change heats up the oceans, the process speeds up." * https://lnkd.in/eczUUbkR Read more https://lnkd.in/esQT4-pg #climatechange #globalwarming #sustainability #antartica #sealevelrise #future

NEW STUDY: For the first time, scientists combined geological samples from the seafloor with sophisticated modelling to reveal the origins of today's Antarctic ice sheet. Today's ice is melting faster than previously assumed—but more in West Antarctica than East Antarctica. The root for this disparity could lie in how the ice sheet formed 34 million years ago. ACEAS co-author Dr Katharina Hochmuth says the ice sheet did not cover the whole continent as scientists previously assumed. It was instead confined to East Antarctica for at least seven million years before advancing towards the West Antarctic coasts. The investigations highlight how different the two regions of the Antarctic ice sheet are, and how they react to external changes—including climate change. “Even a slight warming is enough to cause the ice in West Antarctica to melt again—and that's exactly where we are right now." STORY: https://lnkd.in/gDYMBKdN PAPER: https://lnkd.in/gS8CnVKU University of Tasmania British Antarctic Survey MARUM - Center for Marine Environmental Sciences, University of Bremen Heidelberg University Northumbria University Imperial College London Université de Fribourg - Universität Freiburg Universidad de Granada University of Leicester Texas A&M University Federal Institute for Geosciences and Natural Resources (BGR)

Like a magnifying glass on an anthill, excessive emissions from burning fossil fuels is melting the Antarctic ice sheet. The faster it liquefies, the more we're faced with the dire prospect of extreme sea level rise. Scientists have debated whether a "tipping point" exists for this ice sheet, or a moment when the effects of this melting would be suddenly both irreversible and catastrophic. Now a recent study in the journal Nature Geoscience reveals that such a tipping point may indeed exist. As it turns out, scientists have misunderstood a key aspect of the physical process behind the Antarctic ice sheet's ongoing melting, and therefore have underestimated the ultimate impact of climate change on Antarctica. The British Antarctic Survey researchers discovered that warm ocean water is seeping beneath the Antarctic ice sheet at its so-called "grounding line," or the point at which the ice from a large body rises from the seabed and begins to float. When warm water moves under a grounding line, the ice melts at an accelerated pace and could pass a threshold where the body's ultimate collapse is inevitable. While this process occurs, sea levels will rise at a much faster rate than currently predicted, resulting in millions of people from coastal communities being displaced over the upcoming decades and centuries. Continue reading… Source: https://flip.it/ijlW0k

The results of a survey by the British Antarctic Institute have been published in Nature Geoscience. The report states that warm ocean water is flowing under the ice sheet of Antarctica, which is causing the continent to melt faster than expected, and sea levels to rise faster than predicted. The report warns that if 150 billion tons of ice melts every year at that rate, sea levels will rise by 58 meters when it is all melted. I have written many times on Linkedin about the economic and urban policy issues caused by rising sea levels in coastal areas. I am not a science expert, so I tend to take such articles at face value, but if it is true, the economy, especially in developed countries, will suffer great damage. I would like to hear your various opinions.

Ice cores provide first documentation of rapid Antarctic ice loss in the past . Researchers have uncovered the first direct evidence that the West Antarctic Ice Sheet shrunk suddenly and dramatically at the end of the Last Ice Age, around eight thousand years ago. The evidence, contained within an ice core, shows that in one location the ice sheet thinned by 450 meters -- that's more than the height of the Empire State Building -- in just under 200 years. #ScienceDailynews #InnovativeResearch #NextGenScience #ExploringFrontiers