It is a image.
Photographs from the 1930s were used to create a digital reconstruction of the glacier.
The glaciers of the Norwegian archipelago of Svalbard are the most affected by climate change on the planet.
Over the past three decades, Svalbard has warmed seven times the global average. That is causing the glaciers to melt at an alarming rate, threatening polar bears and other wildlife, and adding to rising sea levels around the globe.
Predicting how quickly the ice might retreat was difficult for a long time. In the mid-20th century, most field measurement started and satellite observations started.
Scientists are using advances in computing to bring old ice back to life. Using black-and-white photos taken during mapping expeditions nearly a century ago, they are creating three-dimensional digital models of how the glaciers looked before modern record-keeping, and illuminating the ways they have changed over a longer stretch of time.
It is a image.
A computer-reconstructed model of a glacier.
It is a image.
A model shows the extent of glacier loss in 2009.
It is a image.
The glacier was modeled in 1936.
It is a image.
The extent was modeled to show in 2009.
In the journal Nature, one of the largest reconstructions to date states that the glaciers of Svalbard could thin twice as fast as they did in the last century.
There is a new administration, an ongoing climate emergency, and a lot of news. Our newsletter will keep you up to date. It will be sent to your inbox.
Emily C. Geyman is a graduate student at the California Institute of Technology and the lead author of the new study. Scientists can use a deeper historical record to see how their models line up with the past.
Ward J.J. van Pelt is an associate professor at Uppsala University in Sweden.
The reconstruction of the glaciers in 1936 shows how much the ice caps shrank between then and 2010. The average rate of loss was over a foot a year.
Glacier change from 1936 to 2010
The model estimates the elevation change.
Glacier change from 1936 to 2010
The model estimates the elevation change.
Nature was published by The New York Times.
The coastline of Svalbard reflects glacier extents.
Geyman et al. are from Nature.
The New York Times has a story by Nadja Popovich.
Rapid warming is disrupting the vast wild landscapes across the planet. Shrinking sea ice and snow cover continued to transform the region last year. The glaciers have been collapsing. Home and infrastructure built atop the frozen ground have been disrupted by the thaw of the ground.
During the winter, the edge of the sea ice is located in Svalbard. Sea ice reflects a lot of the sun's light, so as the ice disappears, more solar energy gets absorbed by the ocean, heating the water. This is the main reason that Svalbard is warming faster than the rest of the globe.
Ms. Geyman and her co-authors used aerial images taken by a Norwegian mapping project in 1936 and 1938 to reconstruct the islands' past. The equipment was simple, a camera mounted to a scout plane.
The pictures owned and managed by the Norwegian Polar Institute capture the drama of the landscape. Ms. Geyman said she was enchanted by the photos.
It is a image.
A model of the glacier in 1936.
It is a image.
Emily Geyman and her colleagues from the Norwegian Polar Institute created a model of 2010 glaciers.
Ms. Geyman had to tell her computer how to see the faded negatives. Picking out points on different photos that show the same feature in the landscape is what this involves.
She placed over 67,000 points on the photos. It took two years. She pointed at her face and said, "I started to have to wear these glasses, I think, because of squinting so much at pixelated images on my screen."
She filled in the gaps with estimates because the terrain was hard to see in the photos.
When they had digital reconstructions of more than 1,500 glaciers, Ms. Geyman and her co-authors compared them with newer images to determine how much ice had melted.
They used these specifications to predict that the average elevation of the glaciers would shrink by between 2.2 and 3 feet a year by the year 2200 if greenhouse gases increase. The pace of retreat that occurred in the 20th century was 1.9 times greater than today's.
Researchers have been creating computer models of glaciers for a long time. Increased processing power has made it possible to reconstruct ice cover across the entire region.
He said that this is a new era where we can look at populations of glaciers.
Mr. Mannerfelt is working on a paper that uses photos taken by Swiss mountaineers between the two world wars to show changes in Switzerland's glaciers. He hopes that other image archives will be able to provide detailed reconstructions of the ice in South America and the Himalayas.
We can make better predictions for the future now that we know what happened.
All Rights Reserved © 2024
