.css-14iz86j-BoldText{font-weight:bold;}Scientists may just have identified Thwaites Glacier's Achilles heel. ITGC Thwaites Glacier. A look at maps … Maps and Graphics. 1). It was named by ACAN for Fredrik T. Thwaites, a glacial geologist, geomorphologist and professor emeritus at the University of Wisconsin–Madison. Warm circumpolar deep water is melting the underside of this floating shelf, leading to an ongoing speedup of Thwaites Glacier. British and American scientists have had to temporarily suspend their investigations at Thwaites because of the Covid-19 crisis. A new expedition hopes to change that. Its ice flow has accelerated by about 50-100 m per year since 2009. Flowing off the west of the Antarctic continent, Thwaites is almost as big as Great Britain. Latitude: -75° 29' 59.99" SLongitude: -106° 44' 59.99" W, Satellite map of Thwaites Glacier in Google Maps. The many faces of Thwaites ice shelf. Over the past 30 years, this glacier has undergone dramatic changes. These deviations reflected the seafloor's undulations beneath the shelf. This in turn will further accelerate thinning of the glacier and grounding line retreat.". Read about our approach to external linking. The cause of the melting is thought to be the influx of relatively warm bottom-water drawn in from the wider ocean. Supreme Court rejects Trump-backed election lawsuit, Covid: Homeless left struggling for shelter. The new information refines the volumes for ingressing warm water that can be considered possible under different scenarios. Thwaites Glacier is located on the Western border of the Antarctic continent. This is a high-resolution map of Thwaites Glacier's thinning ice shelf. Thwaites Glacier (75°30′S 106°45′W / 75.500°S 106.750°W ), sometimes referred to as the Doomsday Glacier, is an unusually broad and vast Antarctic glacier flowing into the Pine Island Bay, part of the Amundsen Sea, east of Mount Murphy, on the Walgreen Coast of Marie Byrd Land. But satellite monitoring indicates this glacier is melting at an accelerating rate. In the 1990s it was losing just over 10 billion tonnes of ice a year. This Antarctic colossus is melting at a rapid rate, dumping billions of tonnes of ice in the ocean every year and pushing up global sea-levels. .css-1xgx53b-Link{font-family:ReithSans,Helvetica,Arial,freesans,sans-serif;font-weight:700;-webkit-text-decoration:none;text-decoration:none;color:#FFFFFF;}.css-1xgx53b-Link:hover,.css-1xgx53b-Link:focus{-webkit-text-decoration:underline;text-decoration:underline;}Read about our approach to external linking. GHOST is an ice- and modeling-based project that will examine the bed and interior of Thwaites Glacier. "When the Eastern Ice Shelf becomes unpinned, the ice will spread out and thin, eventually breaking up, as we can see is happening right now on the (central) glacier tongue," he told BBC News. "And because they are so deep, and so wide - this allows a lot more water to get at, and melt, Thwaites' floating front as well as its ice that rests on the seabed," she told BBC News. The lawsuit sought to invalidate results in four states where President Trump lost the US election. Can shearing of Thwaites glacier slow or stop if humans control greenhouse gas emissions? Currently, Thwaites' ice loss contributes approximately 4% to the annual rise in global sea-levels, with the potential to add 65cm in total should the whole glacier collapse. Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos, .css-1hlxxic-PromoLink:link{color:inherit;}.css-1hlxxic-PromoLink:visited{color:#696969;}.css-1hlxxic-PromoLink:link,.css-1hlxxic-PromoLink:visited{-webkit-text-decoration:none;text-decoration:none;}.css-1hlxxic-PromoLink:link:hover,.css-1hlxxic-PromoLink:visited:hover,.css-1hlxxic-PromoLink:link:focus,.css-1hlxxic-PromoLink:visited:focus{color:#B80000;-webkit-text-decoration:underline;text-decoration:underline;}.css-1hlxxic-PromoLink:link::after,.css-1hlxxic-PromoLink:visited::after{content:'';position:absolute;top:0;right:0;bottom:0;left:0;z-index:2;}Supreme Court rejects Trump-backed election lawsuit. The urgency stems from observations and analyses showing that the amount of ice flowing from Thwaites—and contributing to sea level rise—has doubled in the span of three decades. Our geologists onboard captured most of what they need to reconstruct past ocean and ice changes at Thwaites Glacier, creating maps of geologic features on the seafloor, acquiring history records from marine sediment cores, and picking up a few penguin bones and rocks along the way to age-date past glacial changes. Main navigation. Thwaites Glacier, sometimes referred to as the Doomsday Glacier, is an unusually broad and vast Antarctic glacier flowing into the Pine Island Bay, part of the Amundsen Sea, east of Mount Murphy, on the Walgreen Coast of Marie Byrd Land. Thwaites glacier in West Antarctica are enormous in size and often referred to as the most dangerous glacier on Earth. They trace the path of a network of deep channels that cut through a ridge before joining up to form a major cavity under the ice shelf. Glaciers are huge sheets of ice moving very slowly, and contain vast amounts of … The bedrock below Thwaites and other glaciers is conducive to runaway melting that … Its surface speeds exceed 2 km/yr near its grounding line, and its fastest flowing grounded ice is centred between 50 and 100 km east of Mount Murphy. At 192,000 square kilometres, the Thwaites Glacier is the size of Great Britain or the US state of Florida. They wanted to understand how possible scenarios of future sea level rise might change over time as a result of marine ice sheet instability. The Palmer glides slowly, 400 meters from the face of the ice shelf in front of Thwaites Glacier. "The connected channels that we've mapped in detail for the first time are the potential pathways for deep-ocean warm water to get in and do damage at that point where the glacier is still grounded on the seabed, where it begins to lift up and float," explained BAS colleague Dr Tom Jordan, "but also to melt the base of the ice shelf, which if you weaken will make the ice further upstream in the glacier flow faster.". A plane was also flown back and forth across the shelf to measure small variations in the pull of gravity. Thwaites Glacier is one of the largest glaciers in West Antarctica covering a region of the size of Great Britain (see Fig. Today, it's more like 80 billion tonnes. Its ice flow has accelerated by about 50-100 m per year since 2009. US Pfizer Covid vaccine approved for emergency use, US faces bleak winter amid worst Covid wave yet, Trump's latest, legal longshot to challenge result, Covid: Homeless left struggling for shelter. It is also one of the most rapidly changing glaciers in Antarctica. It appears that costly and sophisticated research by these very dedicated climate scientists has made the amazing discovery that maps the deep channels on the seafloor bathymetry by which warm water reaches the underside of the Thwaites glacier and thus explains how this Doomsday glacier melts. This tells them about the sorts of speeds ice further back in the glacier can achieve as it slides across rock and sediment. At the moment, the eastern side of the ice shelf is hooked on to a large ridge, which gives it stability. Antarctica’s Thwaites Glacier has been in the spotlight in recent years, as scientists have undertaken a multi-part international project to study the vast glacier from all angles. A massive one that poses such risk it's been branded the 'Doomsday Glacier". No-one thinks this will happen in the short-to-medium term, but Thwaites is considered particularly vulnerable in a warming world, and scientists would like to know precisely how fast any changes might occur. It's a majestic sight, with its buoyant front, or "ice shelf", pushing far out to sea and kicking off huge icebergs. Over the past 30 years, the amount of ice flowing out of the region has nearly doubled, and computer models show that over the next several decades, the glacier may lose ice even more rapidly. Maps and Graphics. Thwaites Glacier (75°30′S106°45′W) is an unusually broad and fast Antarctic glacier flowing into Pine Island Bay, part of the Amundsen Sea, east of Mount Murphy, on the Walgreen Coast of Marie Byrd Land. Their scientists sailed a ship equipped with an echo-sounder right up to the glacier's ice cliffs, to trace the shape of the seabed below. "Even before ice shelf break-up, the unpinning and thinning will reduce the buttressing effect of the ice shelf on the glacier upstream of it, resulting in increased ice flow velocity. Read More. Officially called the Thwaites Glacier, this mass of ice nestled into the western edge of Antarctica is melting at an alarming rate. Arriving around 5 a.m., the Palmer begins to map the uncharted perimeter, the multibeam simultaneously mapping the seafloor in front and as far under the shelf as the angle of the sound pulse could extend. The International Thwaites Glacier Collaboration is performing some magnificent science, conducting the most ambitious fieldwork ever undertaken at the tip of what is one of the most significant glaciers on Earth. See the latest updates, context, and perspectives about this story. 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ITGC Logistics Outline, 2 May 2018. "These channels had not been mapped before in this kind of detail, and what we've discovered is that they're actually much bigger than anyone thought - up to 600m deep. By Jonathan AmosBBC Science Correspondent. Thwaites Glacier holds enough ice to drive up sea levels more than 2 feet. Thwaites Glacier (75°30′S 106°45′W) is an unusually broad and fast Antarctic glacier flowing into Pine Island Bay, part of the Amundsen Sea, east of Mount Murphy, on the Walgreen Coast of Marie Byrd Land.Its surface speeds exceed 2 km/yr near its grounding line, and its fastest flowing grounded ice is centred between 50 and 100 km east of Mount Murphy. The Thwaites Glacier is often considered one of the most important when it comes to changes in sea level, but it has been little studied. Thwaites Glacier. These hidden ducts lubricate its collapse into the ocean. Antarctica's Thwaites glacier has warm water from three directions well under it threatening to destroy the ice sheet and raise global sea levels by up to two feet. Video, Covid: Homeless left struggling for shelter, Zodiac Killer: Code-breakers solve San Francisco killer's cipher, US Supreme Court rejects Trump-backed bid to overturn election, Alfred Bourgeois: Second death row inmate executed in two days, Brexit: UK-EU talks continue as Navy boats put on standby, Space tourism: Virgin space plane to fly above new base, Prince William and Kate make red carpet debut with royal children, FKA twigs sues ex-boyfriend Shia LaBeouf over alleged abuse, Covid: Genes hold clues to why some people get severely ill, Aztec skull tower: Archaeologists unearth new sections in Mexico City, Ruhollah Zam: Iran executes journalist accused of fanning unrest, Thwaites: Journey to the 'doomsday glacier', Greenland and Antarctica ice loss accelerating, Deepest point on land found in Antarctica, Satellites record history of Antarctic melting, Coronavirus severely restricts Antarctic science, 'Stunning' seafloor ridges record Antarctic retreat. Thwaites Glacier covers 74,000 square miles—an area the size of Florida—and is particularly susceptible to climate and ocean changes. But the current melting trend would suggest this situation won't last much longer, says BAS's Dr Robert Larter. Now, a UK-US team has surveyed the deep seafloor channels in front of the glacier that almost certainly provide the access for warm water to infiltrate and attack Thwaites' underside. In conducting their survey, scientists also now have a better idea of the general roughness of the seafloor. Investigating Thwaites Glacier Educational Infographic. Thwaites Glacier (75°30′S 106°45′W) is an unusually broad and fast Antarctic glacier flowing into Pine Island Bay, part of the Amundsen Sea, east of Mount Murphy, on the Walgreen Coast of Marie Byrd Land.Its surface speeds exceed 2 km/yr near its grounding line, and its fastest flowing grounded ice is centred between 50 and 100 km east of Mount Murphy. "When we were there in 2019, we were able to get right up to the ice shelf cliffs, and the reason we could do that and make our observations was because the icebergs and sea-ice that have always been there historically are starting to disappear.". The UK and the US joined forces in 2019 to investigate Thwaites. Its fastest flowing grounded ice is centred between 50 and 100 kilometres (31 and 62 mi) east of Mount Murphy. It's information that will be used to try to predict the ice stream's future. New seafloor maps reveal the first clear view of a system of channels that may be helping to hasten the demise of West Antarctica’s vulnerable Thwaites Glacier. Maps That Peer Below Antarctic Ice Show Precarious Position of Key Glacier. A large area of the West Antarctic Ice Sheet flows to the ocean via Thwaites Glacier, which extends over 192,000 sq kms (74,000 sq miles), an area the size of Florida or the island of Britain. Thwaites: 'Doomsday Glacier' vulnerability seen in new maps The icebreaker, the Nathaniel B Palmer, mapped more than 2000 sq km of seafloor in front of the glacier Scientists may just have identified Thwaites Glacier's. Its surface speeds exceed 2 kilometres per year (1.2 miles per year) near its grounding line. Scientists may just have identified Thwaites Glacier's Achilles heel. Robel, along with scientists Helene Seroussi and Gerard Roe used mathematical analysis and computer models to make projections of sea levels in the future. 1).. Over the past 30 years, this glacier has undergone dramatic changes. The icebreaker, the Nathaniel B Palmer, mapped more than 2,000 sq km of seafloor in front of the glacierScientists may just have identified Thwaites Glacier's Achilles heel.This Antarctic colossus is melting at a rapid rate, dumping billions of tonnes of ice in the ocean every year and pushing up global sea-levels.Now, a UK-US team has surveyed the deep seafloor channels The channels are … The Thwaites Glacier is...a glacier. “Not only that… The rheology and topography of the bed affect how quickly Thwaites retreats and contributes to sea-level rise: it could rapidly collapse, or retreat might slow or pause on a subglacial ridge (GHOST Ridge) 70 kilometers inland of the current grounding line. About the ITGC; Thwaites Glacier Facts; ... Maps and Graphics. Velocity map of the Thwaites Glacier catchment, West Antarctica - Volume 50 Issue 168 - Oliver Lang, Bernhard T. Rabus, Stefan W. Dech Think of six football pitches back to back," said Dr Kelly Hogan from the British Antarctic Survey (BAS). Toggle navigation. West Antarctica’s Thwaites Glacier covers 70,270 square miles (182,000 square km), the approximate size of Florida. Currently, Thwaites' ice loss contributes approximately 4% to the annual rise in global sea-levels, with the potential to add 65cm in total should the whole glacier collapse. © 2020 BBC. Thwaites Glacier is one of the largest glaciers in West Antarctica covering a region of the size of Great Britain (see Fig. Currently, Thwaites’ ice loss contributes approximately 4% to the annual rise in global sea-levels, with the potential to add 65cm in total should the whole glacier collapse. Newsweek. “The more this marine ice sheet instability occurs, the wider the range of possible future sea level rise becomes,” Robel says. The latest research is published in two papers in the journal The Cryosphere, and can be accessed here and here. The BBC is not responsible for the content of external sites. The two datasets taken together now provide the best view yet of Thwaites' underlying topography. What the researchers have produced, if you like, is a kind of "stickiness index" to additionally constrain the computer models. Glaciers everywhere might be melting, but only one has earned the most terrifying nickname: the Doomsday Glacier. Thwaites Glacier The International Thwaites Glacier Collaboration. Scientists need real-world data to corral their models so that when they run simulations of possible future behaviour, they get realistic outcomes. By Peter Sinclair | Nov 20, 2020 Runaway sea-level rise resulting from retreat of Antarctica's Thwaites glacier depends on humans' substantially cutting GHG emissions. Teams were due to head back to the glacier this austral summer, but the location's remoteness means the risks are too great should anyone fall ill. 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