How do we know glaciers are shrinking?
Repeat photography and aerial / satellite photo analysis provide evidence of glacier loss in terms of shape and area. The USGS Benchmark Glacier project has collected mass balance data on a network of glaciers in Alaska, Washington, and Montana for decades, quantifying trends of mass loss at all sites. Extensive field data collection at these sites includes twice yearly visits to measure seasonal change of snow/ice at ablation stakes and snow-pit analysis to measure snow density for extrapolating ice gain or loss across the glacier surface.
Emerging technologies, complemented by the availability of satellite imagery, allow USGS scientists to create Digital Elevation Models (DEMs) that provide data on the elevation of glacier ice. By comparing DEMS from different times, scientists calculate ice volume change on a regional scale, broadening the understanding of ice loss and its link to climate.
Learn more: USGS Water Science School: Glaciers and Icecaps
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Glacier retreat in Glacier National Park, Montana
Currently, the volume of land ice on Earth is decreasing, driving consequential changes to global sea level and local stream habitat. Glacier retreat in Glacier National Park, Montana, U.S.A., is one example of land ice loss and glacier change. The U.S. Geological Survey Benchmark Glacier Project conducts glaciological research and collects field...
Florentine, Caitlyn
State of the Earth’s cryosphere at the beginning of the 21st century : glaciers, global snow cover, floating ice, and permafrost and periglacial environments: Chapter A in Satellite image atlas of glaciers of the world
This chapter is the tenth in a series of 11 book-length chapters, collectively referred to as “this volume,” in the series U.S. Geological Survey Professional Paper 1386, Satellite Image Atlas of Glaciers of the World. In the other 10 chapters, each of which concerns a specific glacierized region of Earth, the authors used remotely...
Williams, Richard S.; Ferrigno, Jane G.; Williams, Richard S.; Ferrigno, Jane G.
The United States National Climate Assessment - Alaska Technical Regional Report
The Alaskan landscape is changing, both in terms of effects of human activities as a consequence of increased population, social and economic development and their effects on the local and broad landscape; and those effects that accompany naturally occurring hazards such as volcanic eruptions, earthquakes, and tsunamis. Some of the most prevalent...
Markon, Carl J.; Trainor, Sarah F.; Chapin, F. Stuart; Markon, Carl J.; Trainor, Sarah F.; Chapin, F. Stuart
Fifty-Year Record of Glacier Change Reveals Shifting Climate in the Pacific Northwest and Alaska, USA
Fifty years of U.S. Geological Survey (USGS) research on glacier change shows recent dramatic shrinkage of glaciers in three climatic regions of the United States. These long periods of record provide clues to the climate shifts that may be driving glacier change. The USGS Benchmark Glacier Program began in 1957 as a result of research efforts...
A Century of Retreat at Portage Glacier, South-Central Alaska
Introduction: The Portage Glacier, in south-central Alaska, is viewed by thousands of visitors annually who come to the U.S. Forest Service Begich, Boggs Visitor Center located on the road system between Anchorage and Whittier, Alaska. During the past century, the terminus of the glacier has retreated nearly 5 kilometers to its present location (...
Kennedy, Ben W.; Trabant, Dennis C.; Mayo, Lawrence R.
Satellite Image Atlas of Glaciers of the World
In 1978, the USGS began the preparation of the 11-chapter USGS Professional Paper 1386, 'Satellite Image Atlas of Glaciers of the World'. Between 1979 and 1981, optimum satellite images were distributed to a team of 70 scientists, representing 25 nations and 45 institutions, who agreed to author sections of the Professional Paper concerning either...
Williams, Richard S.; Ferrigno, Jane G.
Hubbard Glacier, Alaska: growing and advancing in spite of global climate change and the 1986 and 2002 Russell Lake outburst floods
Hubbard Glacier, the largest calving glacier on the North American Continent (25 percent larger than Rhode Island), advanced across the entrance to 35-mile-long Russell Fiord during June 2002, temporarily turning it into a lake. Hubbard Glacier has been advancing for more than 100 years and has twice closed the entrance to Russell Fiord during the...
Trabant, Dennis C.; March, Rod S.; Thomas, Donald S.
Satellite image atlas of glaciers of the world -- North America
Williams, Richard S.; Ferrigno, Jane G.
Photogrammetric Data Set, 1957-2000, and Bathymetric Measurements for Columbia Glacier, Alaska
Major changes in the length, speed, surface altitude, and calving rate of Columbia Glacier, Alaska have been recorded with stereo vertical photography acquired on 119 dates from 1957 to 2000. Photogrammetric analysis of this photographic record has resulted in precise measurement of these changes. From 1982 to 2000 Columbia Glacier retreated 12...
Krimmel, Robert M.
Global ice-core research: Understanding and applying environmental records of the past
One way to study Earth’s past environmental conditions is to look at ice cores recovered from glaciers. Every year a layer of snow accumulates on glaciers, like a page in a history book, and eventually turns to ice. Like reading the pages of a history book, analyzing the layers in a glacial ice core for specific chemical and physical components is...
Cecil, L. DeWayne; Green, Jaromy R.; Naftz, David L.
A strategy for monitoring glaciers
Glaciers are important features in the hydrologic cycle and affect the volume, variability, and water quality of runoff. Assessing and predicting the effect of glaciers on water resources require a monitoring program to provide basic data for this understanding. The monitoring program of the U.S. Geological Survey employs a nested approach whereby...
Fountain, Andrew G.; Krimmel, Robert M.; Trabant, Dennis C.
Columbia Glacier, Alaska; research on tidewater glaciers
Krimmel, Robert M.
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.
