USGS scientist Louis Sass assesses an on-glacier weather station on the Kahiltna Glacier in Denali National Park, Alaska. This weather station is located at Kahiltna Base Camp, where climbers attempting to summit Denali begin their ascent. Sultana (Mt. Foraker) is visible in the background.
How many glaciers currently exist in Alaska?
Based on the most recent comprehensive survey in 2011, there were about 27,000 glaciers in Alaska. However, the number of glaciers is a misleading statistic. Scientists are more interested in total glacial land coverage as a measure. The number of glaciers is less important since large ones can split up into several as they retreat. The amount of area glaciers occupy in Alaska is trending downward.
Roughly a third of Alaska’s glaciers have been given official names that can be found in the online Geographic Names Information System.
Learn more: USGS Water Science School - Glaciers: Things to Know
Related
Which mountain in the conterminous U.S. has the most glaciers? Which mountain in the conterminous U.S. has the most glaciers?
Mount Rainier, Washington, at 14,410 feet (4,393 meters), the highest peak in the Cascade Range, is a dormant volcano whose glacier ice cover exceeds that of any other mountain in the conterminous United States. Mount Rainier has approximately 26 glaciers. It contains more than five times the glacier area of all the other Cascade volcanoes combined. Mount Baker (Washington) at 10,778 feet (3,285...
How old is glacier ice? How old is glacier ice?
The age of the oldest glacier ice in Antarctica may approach 1,000,000 years old The age of the oldest glacier ice in Greenland is more than 100,000 years old The age of the oldest Alaskan glacier ice ever recovered (from a basin between Mt. Bona and Mt. Churchill) is about 30,000 years old. Glacier flow moves newly formed ice through the entire length of a typical Alaskan valley glacier in 100...
Are today's glaciers leftovers from the Pleistocene ice age? Are today's glaciers leftovers from the Pleistocene ice age?
Yes and no. It depends on which glaciers you are considering. Parts of the Antarctic Continent have had continuous glacier cover for perhaps as long as 20 million years. Other areas, such as valley glaciers of the Antarctic Peninsula and glaciers of the Transantarctic Mountains may date from the early Pleistocene. For Greenland, ice cores and related data suggest that all of southern Greenland and...
Do ice worms exist? Do ice worms exist?
Yes, ice worms do, in fact, exist! They are small worms that live in glacial ice in Alaska, Washington, Oregon, and British Columbia; they have not been found in glaciers elsewhere. Contrary to stories and songs, they do not give glacier ice its blue color and they don't grow to lengths of 50 feet. These myths were made popular by poet Robert Service and the annual Cordova Iceworm Festival in...
Why is glacier ice blue? Why is glacier ice blue?
Glacier ice is blue because the red (long wavelengths) part of white light is absorbed by ice and the blue (short wavelengths) light is transmitted and scattered. The longer the path light travels in ice, the more blue it appears. Learn more: USGS Water Science School - Glaciers: Things to Know
Where are glaciers found in continental North America? Where are glaciers found in continental North America?
Glaciers exist in both the United States and Canada. Most U.S. glaciers are in Alaska; others can be found in Washington, Oregon, California, Montana, Wyoming, Colorado, and Nevada (Wheeler Peak Glacier in Great Basin National Park). Utah’s Timpanogos Glacier is now a rock glacier (in which the ice is hidden by rocks), and Idaho’s Otto Glacier has melted away. Canada has glaciers in Alberta...
Where on Earth are temperate glaciers located? Where on Earth are temperate glaciers located?
A temperate glacier (as opposed to a polar glacier) is a glacier that’s essentially at the melting point, so liquid water coexists with glacier ice. A small change in temperature can have a major impact on temperate glacier melting, area, and volume. Temperate glaciers exist on the continents of North America, South America, Europe, Africa, and Asia; on both islands of New Zealand; and on the...
How would sea level change if all glaciers melted? How would sea level change if all glaciers melted?
There is still some uncertainty about the full volume of glaciers and ice caps on Earth, but if all of them were to melt, global sea level would rise approximately 70 meters (approximately 230 feet), flooding every coastal city on the planet. Learn more: USGS Water Science School: Glaciers and Icecaps National Snow and Ice Data Center: Facts about Glaciers U.S. Global Change Research Program: Sea...
What are the impacts of glacier loss, other than losing an aesthetic landscape feature? What are the impacts of glacier loss, other than losing an aesthetic landscape feature?
Glaciers act as reservoirs of water that persist through summer. Continual melt from glaciers contributes water to the ecosystem throughout dry months, creating perennial stream habitat and a water source for plants and animals. The cold runoff from glaciers also affects downstream water temperatures. Many aquatic species in mountainous environments require cold water temperatures to survive. Some...
Is there a size criterion for a glacier? Is there a size criterion for a glacier?
While there is no global standard for what size a body of ice must be to be considered a glacier, USGS scientists in Glacier National Park use the commonly accepted guideline of 0.1 square kilometers (about 25 acres) as the minimum size of a glacier. Below this size, ice is generally stagnant and does not have enough mass to move. Learn more: Status of Glaciers in Glacier National Park
What is a glacier? What is a glacier?
A glacier is a large, perennial accumulation of crystalline ice, snow, rock, sediment, and often liquid water that originates on land and moves down slope under the influence of its own weight and gravity. Typically, glaciers exist and may even form in areas where: mean annual temperatures are close to the freezing point winter precipitation produces significant accumulations of snow temperatures...
Weather station on Kahiltna Glacier
USGS scientist Louis Sass assesses an on-glacier weather station on the Kahiltna Glacier in Denali National Park, Alaska. This weather station is located at Kahiltna Base Camp, where climbers attempting to summit Denali begin their ascent. Sultana (Mt. Foraker) is visible in the background.
Taku Range, Juneau Icefield, Alaska
Image of the Taku towers, among the Taku Range at Taku Glacier during the summer of 2019
Image of the Taku towers, among the Taku Range at Taku Glacier during the summer of 2019
Glacier off Sargent Icefield
Landscape view of an un-named glacier off the Sargent Icefield, directly across from Wolverine Glacier, above the Nellie Juan River, in Alaska. Taken during a visit to a wolverine glacier field site as part of a study to examine how alpine areas are changing as temperatures rise in Alaska.
Landscape view of an un-named glacier off the Sargent Icefield, directly across from Wolverine Glacier, above the Nellie Juan River, in Alaska. Taken during a visit to a wolverine glacier field site as part of a study to examine how alpine areas are changing as temperatures rise in Alaska.
Alaska Interior Mountain Range
Alaska Interior mountain range shot with snow capped mountains.
Alaska Interior mountain range shot with snow capped mountains.
South Crillon Glacier
Periodic calving of ice from the snout of South Crillon Glacier.
Periodic calving of ice from the snout of South Crillon Glacier.
Wolverine Glacier Ice
Photo of Wolverine Glacier ice. Wolverine Glacier is in the Kenai Mountains on the coast of south-central Alaska. In 1966 scientists with the USGS began making direct measurements of surface mass balance at Wolverine Glacier, a "benchmark glacier" in Alaska.
Photo of Wolverine Glacier ice. Wolverine Glacier is in the Kenai Mountains on the coast of south-central Alaska. In 1966 scientists with the USGS began making direct measurements of surface mass balance at Wolverine Glacier, a "benchmark glacier" in Alaska.
Columbia Glacier
Kittlitz’s Murrelets are often found in higher numbers near glaciers like the Columbia Glacier in Prince William Sound, Alaska
Kittlitz’s Murrelets are often found in higher numbers near glaciers like the Columbia Glacier in Prince William Sound, Alaska
Surprise Glacier
Surprise Glacier, Harriman Fiord, western Prince William Sound.
Surprise Glacier, Harriman Fiord, western Prince William Sound.
Cataract Glacier
Cataract Glacier, Harriman Fiord, western Prince William Sound, AK.
Cataract Glacier, Harriman Fiord, western Prince William Sound, AK.
Barry Glacier
Barry Glacier, Barry Arm, western Prince William Sound.
Barry Glacier, Barry Arm, western Prince William Sound.
Coxe Glacier
Coxe Glacier, Barry Arm, western Prince William Sound.
Coxe Glacier, Barry Arm, western Prince William Sound.
Portage, Burns and Shakespeare glaciers in Southcentral Alaska
Portage Glacier (right), Burns Glacier (center), Shakespeare Glacier (left) in Southcentral Alaska from the air.
Portage Glacier (right), Burns Glacier (center), Shakespeare Glacier (left) in Southcentral Alaska from the air.
Related
Which mountain in the conterminous U.S. has the most glaciers? Which mountain in the conterminous U.S. has the most glaciers?
Mount Rainier, Washington, at 14,410 feet (4,393 meters), the highest peak in the Cascade Range, is a dormant volcano whose glacier ice cover exceeds that of any other mountain in the conterminous United States. Mount Rainier has approximately 26 glaciers. It contains more than five times the glacier area of all the other Cascade volcanoes combined. Mount Baker (Washington) at 10,778 feet (3,285...
How old is glacier ice? How old is glacier ice?
The age of the oldest glacier ice in Antarctica may approach 1,000,000 years old The age of the oldest glacier ice in Greenland is more than 100,000 years old The age of the oldest Alaskan glacier ice ever recovered (from a basin between Mt. Bona and Mt. Churchill) is about 30,000 years old. Glacier flow moves newly formed ice through the entire length of a typical Alaskan valley glacier in 100...
Are today's glaciers leftovers from the Pleistocene ice age? Are today's glaciers leftovers from the Pleistocene ice age?
Yes and no. It depends on which glaciers you are considering. Parts of the Antarctic Continent have had continuous glacier cover for perhaps as long as 20 million years. Other areas, such as valley glaciers of the Antarctic Peninsula and glaciers of the Transantarctic Mountains may date from the early Pleistocene. For Greenland, ice cores and related data suggest that all of southern Greenland and...
Do ice worms exist? Do ice worms exist?
Yes, ice worms do, in fact, exist! They are small worms that live in glacial ice in Alaska, Washington, Oregon, and British Columbia; they have not been found in glaciers elsewhere. Contrary to stories and songs, they do not give glacier ice its blue color and they don't grow to lengths of 50 feet. These myths were made popular by poet Robert Service and the annual Cordova Iceworm Festival in...
Why is glacier ice blue? Why is glacier ice blue?
Glacier ice is blue because the red (long wavelengths) part of white light is absorbed by ice and the blue (short wavelengths) light is transmitted and scattered. The longer the path light travels in ice, the more blue it appears. Learn more: USGS Water Science School - Glaciers: Things to Know
Where are glaciers found in continental North America? Where are glaciers found in continental North America?
Glaciers exist in both the United States and Canada. Most U.S. glaciers are in Alaska; others can be found in Washington, Oregon, California, Montana, Wyoming, Colorado, and Nevada (Wheeler Peak Glacier in Great Basin National Park). Utah’s Timpanogos Glacier is now a rock glacier (in which the ice is hidden by rocks), and Idaho’s Otto Glacier has melted away. Canada has glaciers in Alberta...
Where on Earth are temperate glaciers located? Where on Earth are temperate glaciers located?
A temperate glacier (as opposed to a polar glacier) is a glacier that’s essentially at the melting point, so liquid water coexists with glacier ice. A small change in temperature can have a major impact on temperate glacier melting, area, and volume. Temperate glaciers exist on the continents of North America, South America, Europe, Africa, and Asia; on both islands of New Zealand; and on the...
How would sea level change if all glaciers melted? How would sea level change if all glaciers melted?
There is still some uncertainty about the full volume of glaciers and ice caps on Earth, but if all of them were to melt, global sea level would rise approximately 70 meters (approximately 230 feet), flooding every coastal city on the planet. Learn more: USGS Water Science School: Glaciers and Icecaps National Snow and Ice Data Center: Facts about Glaciers U.S. Global Change Research Program: Sea...
What are the impacts of glacier loss, other than losing an aesthetic landscape feature? What are the impacts of glacier loss, other than losing an aesthetic landscape feature?
Glaciers act as reservoirs of water that persist through summer. Continual melt from glaciers contributes water to the ecosystem throughout dry months, creating perennial stream habitat and a water source for plants and animals. The cold runoff from glaciers also affects downstream water temperatures. Many aquatic species in mountainous environments require cold water temperatures to survive. Some...
Is there a size criterion for a glacier? Is there a size criterion for a glacier?
While there is no global standard for what size a body of ice must be to be considered a glacier, USGS scientists in Glacier National Park use the commonly accepted guideline of 0.1 square kilometers (about 25 acres) as the minimum size of a glacier. Below this size, ice is generally stagnant and does not have enough mass to move. Learn more: Status of Glaciers in Glacier National Park
What is a glacier? What is a glacier?
A glacier is a large, perennial accumulation of crystalline ice, snow, rock, sediment, and often liquid water that originates on land and moves down slope under the influence of its own weight and gravity. Typically, glaciers exist and may even form in areas where: mean annual temperatures are close to the freezing point winter precipitation produces significant accumulations of snow temperatures...
Weather station on Kahiltna Glacier
USGS scientist Louis Sass assesses an on-glacier weather station on the Kahiltna Glacier in Denali National Park, Alaska. This weather station is located at Kahiltna Base Camp, where climbers attempting to summit Denali begin their ascent. Sultana (Mt. Foraker) is visible in the background.
USGS scientist Louis Sass assesses an on-glacier weather station on the Kahiltna Glacier in Denali National Park, Alaska. This weather station is located at Kahiltna Base Camp, where climbers attempting to summit Denali begin their ascent. Sultana (Mt. Foraker) is visible in the background.
Taku Range, Juneau Icefield, Alaska
Image of the Taku towers, among the Taku Range at Taku Glacier during the summer of 2019
Image of the Taku towers, among the Taku Range at Taku Glacier during the summer of 2019
Glacier off Sargent Icefield
Landscape view of an un-named glacier off the Sargent Icefield, directly across from Wolverine Glacier, above the Nellie Juan River, in Alaska. Taken during a visit to a wolverine glacier field site as part of a study to examine how alpine areas are changing as temperatures rise in Alaska.
Landscape view of an un-named glacier off the Sargent Icefield, directly across from Wolverine Glacier, above the Nellie Juan River, in Alaska. Taken during a visit to a wolverine glacier field site as part of a study to examine how alpine areas are changing as temperatures rise in Alaska.
Alaska Interior Mountain Range
Alaska Interior mountain range shot with snow capped mountains.
Alaska Interior mountain range shot with snow capped mountains.
South Crillon Glacier
Periodic calving of ice from the snout of South Crillon Glacier.
Periodic calving of ice from the snout of South Crillon Glacier.
Wolverine Glacier Ice
Photo of Wolverine Glacier ice. Wolverine Glacier is in the Kenai Mountains on the coast of south-central Alaska. In 1966 scientists with the USGS began making direct measurements of surface mass balance at Wolverine Glacier, a "benchmark glacier" in Alaska.
Photo of Wolverine Glacier ice. Wolverine Glacier is in the Kenai Mountains on the coast of south-central Alaska. In 1966 scientists with the USGS began making direct measurements of surface mass balance at Wolverine Glacier, a "benchmark glacier" in Alaska.
Columbia Glacier
Kittlitz’s Murrelets are often found in higher numbers near glaciers like the Columbia Glacier in Prince William Sound, Alaska
Kittlitz’s Murrelets are often found in higher numbers near glaciers like the Columbia Glacier in Prince William Sound, Alaska
Surprise Glacier
Surprise Glacier, Harriman Fiord, western Prince William Sound.
Surprise Glacier, Harriman Fiord, western Prince William Sound.
Cataract Glacier
Cataract Glacier, Harriman Fiord, western Prince William Sound, AK.
Cataract Glacier, Harriman Fiord, western Prince William Sound, AK.
Barry Glacier
Barry Glacier, Barry Arm, western Prince William Sound.
Barry Glacier, Barry Arm, western Prince William Sound.
Coxe Glacier
Coxe Glacier, Barry Arm, western Prince William Sound.
Coxe Glacier, Barry Arm, western Prince William Sound.
Portage, Burns and Shakespeare glaciers in Southcentral Alaska
Portage Glacier (right), Burns Glacier (center), Shakespeare Glacier (left) in Southcentral Alaska from the air.
Portage Glacier (right), Burns Glacier (center), Shakespeare Glacier (left) in Southcentral Alaska from the air.
Updated Date: March 25, 2025