The realization that the West Antarctic ice sheet was gone in the past is the cause of great concern in the global warming era. This is important because our climate today is fast approaching temperatures like those of a few million years ago. But the ice here is warmer, and moving faster.Īs recently as 120,000 years ago, this area was probably an open ocean – and definitely so in the past 2 million years. Large islands made of volcanic mountain ranges are linked together by the thick blanket of ice. This area was once the ocean bottom, a region where the continent was stretched and broken into smaller blocks with deep seabed between. In West Antarctica the bedrock is far different, with parts that are far deeper. This is where the city-size Conger ice shelf collapsed amid an unusually intense heat wave in March 2022.īelow the ice, recent studies have mapped Antarctica’s bedrock and show much of the west side is below sea level. Most of East Antarctica’s bedrock sits above sea level. Some of these have alpine valleys, cut by the very first glaciers that formed on Antarctica 30 million years ago, when its climate resembled Alberta’s or Patagonia’s. In East Antarctica, the part closer to Australia, the continent is rugged and furrowed, with several small mountain ranges. It reveals two very different landscapes, divided by the Transantarctic Mountains. Recent efforts to combine data from hundreds of airplane and ground-based studies have given us a kind of map of the continent below the ice. What does the buried continent look like – and how does that rocky basement shape the future of the ice in a warming world? Visualizing the world below the ice For Antarctica, that means thinking about the landscape below the ice. Like many geoscientists, I think about how the Earth looks below the part that we can see. As these edges of the ice react, they send a powerful reminder: If even a small part of the ice sheet were to completely crumble into the sea, the impact for the world’s coasts would be severe. NASA's Goddard Space Flight Center Scientific Visualization Studioīut now, as the surrounding air and ocean warm, areas of the Antarctic ice sheet that had been stable for thousands of years are breaking, thinning, melting, or in some cases collapsing in a heap. I have gingerly crossed crevasses, trodden carefully on hard blue windswept ice, and driven for days over the most monotonous landscape you can imagine.Ī map of Antarctica seen from above, most of it the ice sheet, shows the velocity of the ice flow ice. coordinating scientist for a major international research effort on Antarctica’s riskiest glacier – more on that in a moment. As a polar scientist I’ve visited most areas of the ice sheet in more than 20 trips to the continent, bringing sensors and weather stations, trekking across glaciers, or measuring the speed, thickness and structure of the ice.Ĭurrently, I’m the U.S. Breaking, thinning, melting, collapsingĪntarctica is where I work. Its glaciers have always been in motion, but beneath the ice, changes are taking place that are having profound effects on the future of the ice sheet – and on the future of coastal communities around the world. The ice holds enough fresh water to raise sea level by nearly 200 feet. Ted ScambosĪntarctica is a continent comprising several large islands, one of them the size of Australia, all buried under a 10,000-foot-thick layer of ice. A sense of movement also emerges, in a way that no ice-free part of the Earth can convey – the entire landscape is in motion, and seemingly not very happy about it.īroken ice where Thwaites Glacier heads out to sea. It’s a twisted, torn, wrenched landscape. Cliffs and tears, rips in the white blanket emerge, indicating a force that can toss city blocks of ice around like so many wrecked cars in a pileup. These are not just cracks, but canyons large enough to swallow a jetliner, or spires the size of monuments. Cracks appear in the surface, sometimes organized like a washboard, and sometimes a complete chaos of spires and ridges, revealing the pale blue crystalline heart of the ice below.Īs the plane flies lower, the scale of these breaks steadily grows. Little swirls of snow dunes cover the surface.īut as you approach the edge of the ice sheet, a sense of tremendous underlying power emerges. Like a gigantic wedding cake, the frosting of snow on top of the world’s largest ice sheet looks smooth and unblemished, beautiful and perfectly white. Flying over Antarctica, it’s hard to see what all the fuss is about.
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