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Geologic Monitoring


Wrangell-St Elias Mountains, Alaska
Wrangell-St Elias Mountains, Alaska. (Click photo to enlarge)

What are glaciers?

Glaciers are perennial snow or ice masses that move over land.

Why does the National Park Service monitor glaciers?

Glacial monitoring is important because:

  • significant change can occur within a relatively short amount of time (e.g. within a human lifetime).
  • changes in glacial conditions will strongly affect the hydrologic and ecological systems of the area in which the glacier(s) exist.
  • the sensitivity of glaciers to changes in temperature and precipitation make them excellent indicators of climate change.

  • Monitoring Book
  • Resource Facts
  • Case Study

Geological Monitoring Book

Vital Signs Monitored

  1. Glacier mass balance
  2. Glacier terminus position
  3. Glacier area
  4. Glacier velocity

Chapter 6
Glacier Monitoring Techniques (PDF - 1.01MB)

Glaciers are a significant natural resource in Alaska and the Western United States. A large percentage of these glaciers exist within the boundaries of lands managed by the U.S. federal government.

Long term monitoring of glacier change is important because it provides basic data for understanding and assessing past, current, and possible future conditions of the local, regional, and global environment. A basic understanding of local and regional environmental systems is critical for responsible land managment and decision-making.

NPS Glacier Facts

37 parks have active glacial features.

Approximately one fourth (4.6 million acres) of Alaska's glaciers occur within national parks.

More than 98% of Alaska's large, lower elevation glaciers are in retreat, thinning or stagnating (USGS, 2008).

Molnia, B.F., 2008, Glaciers of North America -- Glaciers of Alaska, in Williams, R.S., jr., and Ferrigno, J.G., eds., Satellite images of glaciers of the world: U.S. Geological Survey Professional Paper 1386-K, 525 p.

Monitoring Glaciers in the National Park Service

Case Study: North Cascades National Park, Washington

Photo of Oblique aerial view of Mt Spickard, Silver Glacier and Silver Lake looking south, North Cascades National Park, Washington.
North Cascades National Park, Washington. (click to enlarge)

A long-term glacier monitoring program has been in place at North Cascades National Park since 1993. Visit the park's Glacier Monitoring Program website for more information.

More information will be posted here soon...

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Last Updated: January 03, 2017