The surface of South Cascade Glacier, Washington is mostly exposed ice at the end of summer melt season.
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 years or less. Based on flow rates, it takes less than 400 years for ice to transit the entire 140 + mile length of Bering Glacier, Alaska’s largest and longest glacier.
Learn more: USGS Water Science School - Glaciers: Things to Know
Related
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
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...
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...
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 long can we expect the present Interglacial period to last?
No one knows for sure. In the Devils Hole, Nevada paleoclimate record, the last four interglacials lasted over ~20,000 years with the warmest portion being a relatively stable period of 10,000 to 15,000 years duration. This is consistent with what is seen in the Vostok ice core from Antarctica and several records of sea level high stands. These data suggest that an equally long duration should be...
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...
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...
Was all of Alaska covered by glaciers during the Pleistocene Ice Age?
No--most of interior Alaska, south of the Brooks Range and north of the Alaska Range, was a non-glaciated grassland refuge habitat for a number of plant and animal species during the maximum Pleistocene glaciation. This ice-free corridor also provided one route for humans to move into North America. Learn more: USGS Water Science School - Glaciers: Things to Know
Is glacier ice a type of rock?
Glacier ice, like limestone (for example), is a type of rock. Glacier ice is actually a mono-mineralic rock (a rock made of only one mineral, like limestone which is composed of the mineral calcite). The mineral ice is the crystalline form of water (H 2O). Most glacier ice forms through the metamorphism of tens of thousands of individual snowflakes into crystals of glacier ice. Each snowflake is a...
Where are Earth’s glaciers located?
Glaciers exist on every continent except Australia. Approximate distribution is: 91% in Antarctica 8% in Greenland Less than 0.5% in North America (about 0.1% in Alaska) 0.2% in Asia Less than 0.1% are in South America, Europe, Africa, New Zealand, and Indonesia.
South Cascade Glacier, Washington
The surface of South Cascade Glacier, Washington is mostly exposed ice at the end of summer melt season.
Ice core extracted from Wolverine Glacier, Alaska
USGS scientist, Chris McNeil, measures and weighs an ice core extracted from Wolverine Glacier to determine the density of the firn layer.
USGS scientist, Chris McNeil, measures and weighs an ice core extracted from Wolverine Glacier to determine the density of the firn layer.
Drilling an Ice Core
Researchers start drilling an ice core in the Greater Yellowstone Ecosystem.
Researchers start drilling an ice core in the Greater Yellowstone Ecosystem.
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 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.
Researchers Pulling a Deep Ice Core Segment
Mike Jayred, Nathan Challman, Rachel Reckin, and Danny Stahle work to lift an section of ice core from several meters deep in the ice patch.
Mike Jayred, Nathan Challman, Rachel Reckin, and Danny Stahle work to lift an section of ice core from several meters deep in the ice patch.
Mapping the glacier's edge in Glacier National Park.
Mapping the glacier's edge in Glacier National Park.
Mapping the glacier's edge in Glacier National Park.
Layered Ice
An ice jam on the East Branch Wesserunsett Stream in Athens, Maine in January 2014 left 3-5 ft ice walls on the riverbanks. On a January 21, 2014 site visit Nick Stasulis and Charlie Culbertson chisled away some of the ice wall so a discharge measurement could be made.
An ice jam on the East Branch Wesserunsett Stream in Athens, Maine in January 2014 left 3-5 ft ice walls on the riverbanks. On a January 21, 2014 site visit Nick Stasulis and Charlie Culbertson chisled away some of the ice wall so a discharge measurement could be made.
Surprise Glacier
Surprise Glacier, Harriman Fiord, western Prince William Sound.
Surprise Glacier, Harriman Fiord, western Prince William Sound.
PubTalk 2/2008 — Alaska's Rivers of Ice
USGS scientist Bruce Molnia, discusses the impact of changing climate and conditions on Earth's glaciers
By Bruce Molnia, Geologist
See excerpts from this full-length film feature showing:
USGS scientist Bruce Molnia, discusses the impact of changing climate and conditions on Earth's glaciers
By Bruce Molnia, Geologist
See excerpts from this full-length film feature showing:
PubTalk 12/2005 — Frozen in Time
How Ice Cores Are Revealing the Composition and Temperature of Earth's Atmosphere During the Past Million Years
by Todd Hinkley, Geologist
How Ice Cores Are Revealing the Composition and Temperature of Earth's Atmosphere During the Past Million Years
by Todd Hinkley, Geologist
Layers of Ice, Hayden Glacier
This picture was taken from the base of the Hayden Glacier in the Three Sisters Wilderness Area.
This picture was taken from the base of the Hayden Glacier in the Three Sisters Wilderness Area.
Ice Queen
Block of Ice on Vitus Lake, from Bering Glacier, Alaska
Block of Ice on Vitus Lake, from Bering Glacier, Alaska
Related
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
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...
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...
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 long can we expect the present Interglacial period to last?
No one knows for sure. In the Devils Hole, Nevada paleoclimate record, the last four interglacials lasted over ~20,000 years with the warmest portion being a relatively stable period of 10,000 to 15,000 years duration. This is consistent with what is seen in the Vostok ice core from Antarctica and several records of sea level high stands. These data suggest that an equally long duration should be...
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...
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...
Was all of Alaska covered by glaciers during the Pleistocene Ice Age?
No--most of interior Alaska, south of the Brooks Range and north of the Alaska Range, was a non-glaciated grassland refuge habitat for a number of plant and animal species during the maximum Pleistocene glaciation. This ice-free corridor also provided one route for humans to move into North America. Learn more: USGS Water Science School - Glaciers: Things to Know
Is glacier ice a type of rock?
Glacier ice, like limestone (for example), is a type of rock. Glacier ice is actually a mono-mineralic rock (a rock made of only one mineral, like limestone which is composed of the mineral calcite). The mineral ice is the crystalline form of water (H 2O). Most glacier ice forms through the metamorphism of tens of thousands of individual snowflakes into crystals of glacier ice. Each snowflake is a...
Where are Earth’s glaciers located?
Glaciers exist on every continent except Australia. Approximate distribution is: 91% in Antarctica 8% in Greenland Less than 0.5% in North America (about 0.1% in Alaska) 0.2% in Asia Less than 0.1% are in South America, Europe, Africa, New Zealand, and Indonesia.
South Cascade Glacier, Washington
The surface of South Cascade Glacier, Washington is mostly exposed ice at the end of summer melt season.
The surface of South Cascade Glacier, Washington is mostly exposed ice at the end of summer melt season.
Ice core extracted from Wolverine Glacier, Alaska
USGS scientist, Chris McNeil, measures and weighs an ice core extracted from Wolverine Glacier to determine the density of the firn layer.
USGS scientist, Chris McNeil, measures and weighs an ice core extracted from Wolverine Glacier to determine the density of the firn layer.
Drilling an Ice Core
Researchers start drilling an ice core in the Greater Yellowstone Ecosystem.
Researchers start drilling an ice core in the Greater Yellowstone Ecosystem.
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 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.
Researchers Pulling a Deep Ice Core Segment
Mike Jayred, Nathan Challman, Rachel Reckin, and Danny Stahle work to lift an section of ice core from several meters deep in the ice patch.
Mike Jayred, Nathan Challman, Rachel Reckin, and Danny Stahle work to lift an section of ice core from several meters deep in the ice patch.
Mapping the glacier's edge in Glacier National Park.
Mapping the glacier's edge in Glacier National Park.
Mapping the glacier's edge in Glacier National Park.
Layered Ice
An ice jam on the East Branch Wesserunsett Stream in Athens, Maine in January 2014 left 3-5 ft ice walls on the riverbanks. On a January 21, 2014 site visit Nick Stasulis and Charlie Culbertson chisled away some of the ice wall so a discharge measurement could be made.
An ice jam on the East Branch Wesserunsett Stream in Athens, Maine in January 2014 left 3-5 ft ice walls on the riverbanks. On a January 21, 2014 site visit Nick Stasulis and Charlie Culbertson chisled away some of the ice wall so a discharge measurement could be made.
Surprise Glacier
Surprise Glacier, Harriman Fiord, western Prince William Sound.
Surprise Glacier, Harriman Fiord, western Prince William Sound.
PubTalk 2/2008 — Alaska's Rivers of Ice
USGS scientist Bruce Molnia, discusses the impact of changing climate and conditions on Earth's glaciers
By Bruce Molnia, Geologist
See excerpts from this full-length film feature showing:
USGS scientist Bruce Molnia, discusses the impact of changing climate and conditions on Earth's glaciers
By Bruce Molnia, Geologist
See excerpts from this full-length film feature showing:
PubTalk 12/2005 — Frozen in Time
How Ice Cores Are Revealing the Composition and Temperature of Earth's Atmosphere During the Past Million Years
by Todd Hinkley, Geologist
How Ice Cores Are Revealing the Composition and Temperature of Earth's Atmosphere During the Past Million Years
by Todd Hinkley, Geologist
Layers of Ice, Hayden Glacier
This picture was taken from the base of the Hayden Glacier in the Three Sisters Wilderness Area.
This picture was taken from the base of the Hayden Glacier in the Three Sisters Wilderness Area.
Ice Queen
Block of Ice on Vitus Lake, from Bering Glacier, Alaska
Block of Ice on Vitus Lake, from Bering Glacier, Alaska
Updated Date: March 25, 2025