Latest news with #Bedmap2
Yahoo
21-03-2025
- Science
- Yahoo
New Map Shows What Ice-Free Antarctica Looks Like
Millions of years ago, the Antarctic continent was a lush jungle. Millions of years from now, it may be jungle again. But for all of human history, Antarctica has been ice-covered and desolate. Explorers struggled to survive, and researchers struggled to retrieve the few accessible geological samples, hoping to glimpse what lay under the ice. Now, a new model allows us to peel back the frozen white layers and see the land beneath. Called Bedmap3, the model is the most detailed and accurate map of the Antarctic continent ever completed. An International scientific team led by the British Antarctic Survey (BAS) used over 60 years of information gathered by plane, ship, satellite, and even dogsled. In total, they integrated 82 million data points, double the amount used in Bedmap2, the previous generation. To look beneath the 27 million cubic kilometers of ice, researchers used radar, sound waves, and gravity measurements. This leap forward is thanks to recent surveys in under-explored regions of East Antarctica, including the South Polar area. The map shows the location and size of the massive ice sheets based on 277 ice surveys over the past 60 years. The BAS team, led by glaciologist Hanish Pritchard, estimates a mean ice thickness of 1,948m. The area covered by ice is 13.63 million square kilometers, almost twice the size of Australia. The real importance of Bedmap3 is that it will improve predictions of ice loss and sea level rise. Pritchard says the map will help researchers "investigate how the ice will flow across the continent as temperatures rise." Already, the secrets of the continent's rocky underpinning have provided a worrying hint at Antarctica's future. Much of the ice rests on bedrock below sea level. This ice can melt quickly thanks to incursions of warm ocean water. Thanks to this latest research, if it melts, we know it would raise sea levels by 58m. Bedmap3 is a fascinating glimpse into a hidden world. But it's also a grave reminder of how that buried land is quickly rising to the surface.
Yahoo
19-03-2025
- Science
- Yahoo
This is what Antarctica looks like under the ice in most-detailed ever map of the continent
When you buy through links on our articles, Future and its syndication partners may earn a commission. Scientists have unveiled the most detailed map yet of the landscape hidden beneath Antarctica's ice. The high-resolution map reveals what the frozen continent looks like beneath its miles-thick blanket of ice and snow, and will help researchers predict how Antarctica might evolve in a fast-warming climate. "Imagine pouring syrup over a rock cake [or a chocolate chip cookie, if that's more familiar to you] — all the lumps, all the bumps, will determine where the syrup goes and how fast," Hamish Pritchard, a glaciologist at the British Antarctic Survey (BAS) and the lead author of a new study outlining the research, said in a statement. The same process will occur in Antarctica if a significant amount of the ice sheet melts, Pritchard said. "Some ridges will hold up the flowing ice; the hollows and smooth bits are where that ice could accelerate," he said. Related: When was the last time Antarctica was ice-free? Bedmap3 builds on two previous studies that digitally stripped Antarctica of its ice. The new map incorporates all of the data used for Bedmap1 and Bedmap2 — including measurements gathered by planes, satellites, ships and even dog-drawn sleds. But the team also sourced an extra 52 million data points to refine these previous results, according to the study, published March 10 in the journal Scientific Data. In total, more than six decades' worth of data was compiled to construct Bedmap3, the researchers said in the statement. "This is the fundamental information that underpins the computer models we use to investigate how the ice will flow across the continent as temperatures rise," Pritchard said. The new map is color coded to show the height of Antarctica's bedrock above sea level, highlighting the continent's tallest mountains and deepest valleys. The topography is revealed in the finest detail yet, providing new insight into understudied areas, including around the South Pole, according to the statement. The researchers used radar, seismic and gravity measurements to map the bedrock and estimate the thickness of the ice sheet above it. Against their expectations, they found that the place with the thickest ice in Antarctica is an unnamed canyon in Wilkes Land, a district in the east of the continent. Previous surveys placed Antarctica's thickest ice in the Astrolabe Basin in Adélie Land. The difference in ice thickness between the two areas is small: The Astrolabe Basin has a thickness of around 2.9 miles (4.7 kilometers), while Wilkes Land is almost 3 miles (4.8 km) thick, according to the study. The new research also reveals, in unprecedented detail, the shape of the ice sheet and ice shelves that float around the fringes of the continent. RELATED STORIES —Ocean's 'heart' is slowing down — and it will affect the entire planet's circulation —Massive Antarctic icebergs' split from glaciers may be unrelated to climate change —1st map of Antarctica's green space unveiled. Here's what it shows. "In general, it's become clear the Antarctic Ice Sheet is thicker than we originally realized and has a larger volume of ice that is grounded on a rock bed sitting below sea level," study co-author Peter Fretwell, a mapping specialist and geographic information officer at the BAS, said in the statement. Although thickness in itself is not a problem, the fact that much of the ice sits below sea level is concerning, because relatively warm seawater can flood into the ice sheet, Fretwell said. "This puts the ice at greater risk of melting," he added. "What Bedmap3 is showing us is that we have got a slightly more vulnerable Antarctica than we previously thought," Fretwell added.
