Glaciers - National Snow and Ice Data Center
网页Glaciers begin to form when snow remains in the same area year round, where enough snow accumulates to transform into ice. Each year, new layers of snow bury and compress the previous layers. This compression forces the snow to recrystallize, initially forming grains similar to the size and shape of sugar grains.
Learn - National Snow and Ice Data Center
网页Two categories of glaciers exist: ice sheets and alpine glaciers. Ice sheets cover vast areas of land in broad domes. Alpine glaciers, are smaller, and found not only at the poles, but in high mountain regions across the globe.
Glacier Quick Facts - National Snow and Ice Data Center
网页A glacier is an accumulation of ice and snow that slowly flows over land. Alpine glaciers are frozen rivers of ice, slowly flowing under their own weight down mountainsides and into valleys. Ice sheets exist only on Greenland and Antarctica, and they spread out in broad domes in multiple directions. A group of people explore the Perito Moreno ...
Science of Glaciers - National Snow and Ice Data Center
网页Glaciers move by internal deformation of the ice, and by sliding over the rocks and sediments at the base. The weight of overlying snow, firn, and ice, and the pressure exerted by upstream and downstream ice deforms glacier ice, in a phenomenon known as creep. A glacier may slide on a thin layer of water at its base.
Why Glaciers Matter - National Snow and Ice Data Center
网页Why they matter. Glaciers, slow-moving rivers of ice, have sculpted mountains and carved valleys throughout Earth's history. They continue to flow and shape the landscape in many places today. But glaciers affect much more than the landscape. Glacier melt delivers nutrients into lakes, rivers, and oceans. Those nutrients can drive blooms of ...
Homepage | National Snow and Ice Data Center
网页Snow Today. Monthly analyses and daily data images of snow conditions in near-real time across the Western United States using a combination of satellite data and surface observations. Since 2007, the Arctic sea ice minimum has dropped below 5 million square kilometers (1.93 million square miles) every year, except in 2009, 2013, and 2014, when ...
GLIMS - National Snow and Ice Data Center
网页GLIMS is an international project to inventory the world’s glaciers and to create a comprehensive, global database of land ice through repeat surveys. This data collection’s primary data product is the GLIMS Glacier Database. The glacier database includes measurements of glacier geometry, glacier area, snowlines, supraglacial lakes and rock ...
Seeking the world’s largest glaciers - National Snow and Ice Data …
网页2019年10月31日 · The takeaway. Windnagel spent five weeks working on her project at the WGMS office in Zurich. According to the GLIMS data set, the three largest glaciers in the world are Vatnajokull Glacier in Iceland, Flade Isblink Ice Cap in Greenland, and Seller Glacier in Antarctica. On the other hand, according to the RGI data set, the three largest ...
The story is in the ice: Documenting climate change through the …
网页2024年8月12日 · They were programmed to snap continuous shots of glaciers during every hour of daylight for months or years on end. These were the photos that would eventually end up at NSIDC. In addition to the time-lapse photography, the project also captured beauty shots, which focused on the character of ice, and repeat photographic sequences taken …
What are glacial lakes? | National Snow and Ice Data Center
网页2022年2月15日 · A glacial lake is a body of water that originates from a glacier. It typically forms at the foot of a glacier, but may form on, in, or under it. As Earth’s climate warms, the world’s glaciers are shrinking, increasing freshwater outputs to all kinds of glacial lakes. Some communities depend on glacial meltwater for seasonal irrigation or ...