How do we know glaciers are shrinking?
In addition to qualitative methods like Repeat Photography, USGS scientists collect quantitative measurements of glacier area and mass balance to track how some glaciers are retreating (Glacier Monitoring Studies). For example, ablation stakes show the seasonal gain and loss of snow, snow-pit analyses measure density of snow, and precision GPS measurements document the glacier margin. Also, because on-site GPS measurement of individual glaciers is expensive and labor intensive, aerial photograph analysis is used to determine glacier area through digitization of glacier margins.
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Does the USGS monitor global warming?
What is the difference between global warming and climate change?
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How many glaciers currently exist in Alaska?
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Was all of Alaska covered by glaciers during the Pleistocene Ice Age?
Is glacier ice a type of rock?
How much of the Earth's water is stored in glaciers?
How does present glacier extent and sea level compare to the extent of glaciers and global sea level during the Last Glacial Maximum (LGM)?
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Glaciers Rapidly Shrinking and Disappearing: 50 Years of Glacier Change in Montana
The warming climate has dramatically reduced the size of 39 glaciers in Montana since 1966, some by as much as 85 percent, according to data released by the U.S. Geological Survey and Portland State University.
EarthView–As Glaciers Worldwide Are Retreating, One Defies the Trend
In this Landsat EarthView, one glacier in Chile bucks the global trend:
Fifty Years of Glacier Change Research in Alaska
ANCHORAGE, Alaska — This year marks the 50th anniversary of one of the longest continuous glacier research efforts in North America.
From Icefield to Ocean - What Glacier Change Might Mean for the Future of Alaska
Frozen bodies of ice cover nearly 10 percent of the state of Alaska, but the influence of glaciers on the environment, tourism, fisheries, hydropower, and other important Alaska resources is rarely discussed.
Melting Glaciers Increase the Flow of Carbon to Downstream Ecosystems
ANCHORAGE, Alaska Melting glaciers are not just impacting sea level, they are also affecting the flow of organic carbon to the world’s oceans, according to new research that provides the first ever global-scale estimates for the storage and release of organic carbon from glaciers.
Rare Insect Found Only in Glacier National Park Imperiled by Melting Glaciers
The persistence of an already rare aquatic insect, the western glacier stonefly, is being imperiled by the loss of glaciers and increased stream temperatures due to climate warming in mountain ecosystems, according to a new study released in Freshwater Science.
Washington’s Benchmark Glacier Still Shrinking
TACOMA, Wash. — Washington’s only “benchmark” glacier continues to lose mass as a result of changes in climate, according to a report by the U.S. Geological Survey.
Glaciers Retreating in Asia
Many of Asia’s glaciers are retreating as a result of climate change.
Salazar Releases Long-Term Report Detailing Glaciers Shrinking in Alaska and Washington
A report on long-term glacier measurements released today by Secretary of the Interior Ken Salazar shows that glaciers are dramatically changing in mass, length and thickness as a result of climate change.
Most Alaskan Glaciers Retreating, Thinning, and Stagnating, Says Major USGS Report
Most glaciers in every mountain range and island group in Alaska are experiencing significant retreat, thinning or stagnation, especially glaciers at lower elevations, according to a new book published by the U.S. Geological Survey. In places, these changes began as early as the middle of the 18th century.
Decline of World's Glaciers Expected to Have Global Impacts Over This Century
The great majority of the world’s glaciers appear to be declining at rates equal to or greater than long-established trends, according to early results from a joint NASA and United States Geological Survey (USGS) project designed to provide a global assessment of glaciers. At the same time, a small minority of glaciers are advancing.
Melting Glaciers to Methane Gasses
Nearly 300 scientists from the U.S. Geological Survey will present papers and posters describing their earth-science research, during the annual meeting of the American Geophysical Union (AGU), at the Moscone Convention Center in San Francisco, December 10 – 14.
Grinnell Glacier Ridge animation
Animated gif of Grinnell Glacier Rdige 1910 - 2017
Sperry Glacier perimeter: 1966,1998, 2005, 2015.
This image shows the perimeter of Sperry Glacier in Glacier National Park in 1966,1998, 2005, and 2015.
Chaney Glacier perimeter: 1966, 1998, 2005, 2015.
This image shows the perimeter of Chaney Glacier in Glacier National Park in 1966, 1998, 2005, and 2015.
Rainbow Glacier perimeter: 1966, 1998, 2005, 2015.
This image shows the perimeter of Rainbow Glacier in Glacier National Park: 1966, 1998, 2005, 2015.
Swiftcurrent Glacier 1910 - 2016 animation
Swiftcurrent Glacier 1910 - 2016 animation
USGS Public Lecture: Warm Ice—Dynamics of Rapidly Changing Glaciers
- Glacier Numerology – The how big, how long, how thick, how much, how often, of glacier science.
- Glacier Photography – While a picture may be worth a thousand words, a collection of images may tell a complete forensic story.
- Glacier Geophysics – How new technologies are being introduced to reexamine and refine decades old glacier analyses.
