Ice in Motion: 50 years of ice in motion.
How have the great glaciers changed? Alaska, Greenland or Antarctica ? NASA has the answers thanks to new images collected over nearly 50 years by its satellites.
The American Geophysical Union in San Francisco has published videos with these images using data from its satellites, including missions NASA-US Geological Survey Landsat from 1972.
Thanks to them we can verify the dramatic changes that are taking place in the glaciers. What can be deduced from them? The hubbard glacier is one of the largest in Alaska with 122km , and also one of the ones that has most attracted the attention of scientists, since it has not stopped advancing since 1980. This means that the faster a glacier advances, the faster it melts.
Furthermore, starting in the year 2000, NASA satellites record how the melting in Greenland occurs faster and faster , and how that ice ends up becoming lagoons. While in the Antarctica It can be seen from space how hidden lakes begin to be created under the snow during the winter.
Using mission images Landsat dating from 1972 , and continuing through 2019, the glaciologist Mark Fahnestock , from the University of Alaska Fairbanks, has stitched together six-second time-lapses of every glacier in Alaska and Canada's Yukon River, from winter to summer.
This video is the result of how have the glaciers advanced since then . “We are starting to get a historical record of glacier velocities. That way we'll be able to see how fast that surface is shrinking as things speed up, or where it's thickening and where it's rising to the surface,” says Mark.
From the result of the current climate, with global warming, you can see how the glaciers in Alaska respond in different ways. For example, some stop for a few years, others mutate into lakes; in short, they show patterns that give scientists clues about what drives these changes.
Another of the most striking glaciers is the Columbia In alaska. Is about one of the fastest moving in the world , and that since 1980 has begun to retreat. What the Landsat satellite shows is that in 2019 it was 12.4 miles (20 kilometers) upstream . By comparison, the Hubbard Glacier which has advanced 3 miles (5 km) in the last 48 years.
The images captured by NASA satellites on the glaciers.