Research shows continued decline of Oregon's largest glacier

Sep 07, 2010
Collier Glacier in the Oregon Cascade Range once filled this valley - note marks on North Sister, at left, from its maximum size more than 100 years ago. It's now shrunk to less than half of its previous mass. (Photo courtesy of Oregon State University)

An Oregon State University research program has returned to Collier Glacier for the first time in almost 20 years and found that the glacier has decreased more than 20 percent from its size in the late 1980s.

The findings are consistent with all over the world and provide some of the critical data needed to help quantify the effects of global change on glacier retreat and associated .

Flowing down the flanks of the Three Sisters in the central Oregon Cascade Range, Collier Glacier is at an elevation of more than 7,000 feet. It's one of the largest glaciers in Oregon and is on a surprisingly short list - maybe 100 in the entire world - of glaciers that have been intensively studied and monitored for extended periods of time.

Glacier monitoring is difficult, dangerous and labor-intensive, OSU researchers say, and the current work, supported by the National Science Foundation, is showing an ice mass that by now has shrunk to about half of its peak size in the 1850s, when it once was nearly two miles long. Monitoring has been aided by records from early Oregon mountaineering clubs, particularly the Mazamas, founded in 1894 on the summit of Mount Hood.

A research program that began last year and is continuing this summer is now finding some rocks that are being exposed to daylight for the first time in thousands of years.

"Glaciers can tell us a lot about climate change, because they respond to both changes in temperature and precipitation," said Peter Clark, an OSU professor of geosciences who conducted the last studies on Collier Glacier in the late 1980s and early 1990s. "They are like a checking account where you make both deposits and withdrawals, and can see the long-term effects of climate change, through the year-to-year variation in the balance between the two."

This video is not supported by your browser at this time.

The studies on Collier Glacier are now being conducted by Cody Beedlow, an OSU graduate student working with Clark, who visits the glacier throughout the year. Beedlow and assistants have packed in an automatic weather station that provides data on temperature, humidity, and short- and long-wave radiation. Other studies are made by drilling into the ice and inserting stakes to measure the amount of melting.

"Even to get up onto the glacier in the summer you need to travel pretty fast and light, before the next storm front moves in," Beedlow said. "We usually start hiking in at night with headlamps, and often get off the glacier just as the clouds are piling up. For this kind of science you have to take your opportunities when you can find them."

The research in the 1980s and 90s showed the glacier losing mass in four of the five years studied, and it also lost mass last year, Beedlow said. Researchers have been able to get in to the glacier earlier in the season than they had previously, he said, providing important new data.

The glaciers in the Pacific Northwest, such as Collier and another large ice mass on Mount Hood, Eliot Glacier, are there primarily because of massive winter snowfall - more than 20 feet at times on the Three Sisters - which does not all melt during the summer. Elsewhere in the world where it's much colder, such as Antarctica, there's very little snowfall but the temperature is so cold that snowfall remains almost permanently.

But in most of the world, including the Pacific Northwest, have been in a slow global retreat since the end, in the late-1800s, of a 600-year period called the "Little Ice Age," Clark said. Some of that melting will cause a noticeable increase in sea level, and some water resources will be affected where glacial fields feed irrigation streams and reservoirs.

"There will be some ecological and agricultural impacts from glacier loss," Clark said. "But from our perspective, studies such as what we're doing on Collier Glacier give very valuable information to help understand past and current climate changes. They are very good barometers of climate effects."

Long-term studies of Collier Glacier, through scientific research and observations made by examining old photographs, suggest it's now about half of the mass it was 150 years ago. It appears to lose mass most quickly during El Nino events, and also had a period of rapid decline from 1924-34.

Some of the locations where researchers now camp would have been several hundred feet deep in ice in the 1800s.

Explore further: The mysteries of Antarctic sea ice

Related Stories

2 more glaciers gone from Glacier National Park

Apr 07, 2010

(AP) -- Glacier National Park has lost two more of its namesake moving icefields to climate change, which is shrinking the rivers of ice until they grind to a halt, a government researcher said Wednesday.

Melting glacier worries scientists

Jul 25, 2005

Scientists monitoring a Greenland glacier have found it is moving into the sea three times faster than a decade ago, The Independent reported Monday.

Scientists expect increased melting of mountain glaciers

Jan 20, 2006

Sea level rise due to increased melting of mountain glaciers and polar ice caps will be much lower in the 21st Century than previously estimated. However, decay of mountain glaciers in due to global warming will be much more ...

Tasman Glacier retreat extreme

Apr 23, 2008

The Tasman Glacier is retreating faster than ever and will ultimately disappear, glaciologists at Massey University are warning.

Recommended for you

Tropical Storm Genevieve forms in Eastern Pacific

Jul 25, 2014

The seventh tropical depression of the Eastern Pacific Ocean formed and quickly ramped up to a tropical storm named "Genevieve." NOAA's GOES-West satellite captured an infrared image of the newborn storm ...

User comments : 5

Adjust slider to filter visible comments by rank

Display comments: newest first

ArtflDgr
1 / 5 (3) Sep 07, 2010
Consistent with glacial retreat all over the world?

what about the upper Indus and upper Yarkand River basins? In the Karakoram Himalaya, many have started thickening and advancing.

A 2006 survey of 5,020 glaciers in the mountains of western China and the Tibetan Plateau found widely differing rates of reduction. It also found 894 glaciers, about 18%, have advanced in recent decades.

Few glaciers anywhere in the inner Asian mountains meet the criteria of the World Glacier Monitoring Service, and hence have not been tracked by it.

The glacier cover of High Asia exceeds 110,000 square kilometers, the number of identifiable glaciers more than 50,000. There are major concentrations in about a dozen mountain ranges, forming watersheds of all the major rivers of the central, south and south-east Asian mainland. The Upper Indus and Yarkand basins have around 21,000 square kilometers of glaciers, the larger fraction in the Greater Karakoram, or about 16,500 square kilometers.
ArtflDgr
1 / 5 (3) Sep 07, 2010
www.physorg.com/n...251.html

Estimates of the rate of ice loss from Greenland and West Antarctica, one of the most worrying questions in the global warming debate, should be halved, according to Dutch and US scientists.

ArtflDgr
1 / 5 (3) Sep 07, 2010
With glacial isostatic adjustment modelled in, the loss from Greenland is put at 104 gigatonnes, plus or minus 23 gigatonnes, and 64 gigatonnes from West Antarctica, plus or minus 32 gigatonnes.

These variations show a large degree of uncertainy, but Vermeersen believes that even so a clearer picture is emerging on icesheet loss.

"The corrections for deformations of the Earth's crust have a considerable effect on the amount of ice that is estimated to be melting each year," said Vermeersen, whose team worked with NASA's Jet Propulsation Laboratory and the Netherlands Institute for Space Research.

"We have concluded that the Greenland and West Antarctica ice caps are melting at approximately half the speed originally predicted."
Shootist
1 / 5 (3) Sep 07, 2010
Consistent with glacial retreat all over the world?



There are several north facing glaciers in Glacier National Park that are growing.

Regardless, glaciers have been generally shrinking for 10,000 years. Nothing to see here, move along.
Jimee
5 / 5 (3) Sep 08, 2010
The article stated that the glaciers, "in most of the world...have been in slow global retreat...". That may have been meant as a caveat to remember regional conditions which may not follow the general warming trend in lock step with most other places in the world.