Featured Research

from universities, journals, and other organizations

Scientists Rewrite Laws Of Glacial Erosion

Date:
August 15, 2003
Source:
Michigan State University
Summary:
Glaciers, it turns out, aren't so different from people – they can gain weight in their bottoms and be less active, scientists have discovered.

EAST LANSING, Mich. – Glaciers, it turns out, aren't so different from people – they can gain weight in their bottoms and be less active, scientists have discovered.

Glaciers, the heavyweights of landscape erosion, grow not just from snow accumulating on their surfaces but also from beneath by freezing of meltwater which can affect the rate at which they can erode, according to a team of scientists, including one from Michigan State University.

Their discovery, reported in a cover story in the Aug. 14 issue of the international science journal Nature, paints a new picture of how glaciers sculpture and erode the earth's landscapes.

"Glaciers have a profound effect on the landscape, especially in mountainous regions, and this research allows us to understand how glaciers accomplish this," said Grahame Larson, a professor of geological sciences at MSU.

Larson was part of a team of scientists who made winter treks to Alaskan and Icelandic glaciers to understand how glaciers erode and transport sediment, research funded by the National Science Foundation and the Cold Regions Research and Engineering Laboratory in Hanover, N.H.

The researchers' interest was sparked when they observed that fountains of meltwater rushing from some glacier margins spawned icy rims. They eventually were able to link this phenomenon of nature to the less lyrical but instantly identifiable event of creating ice when one pops open a can of very cold soda just pulled from an ice chest.

Larson explained that rapidly transferring ice-cold water from a high pressure environment – be it the inside of a can of soda or beneath a hulking glacier – to a lower pressure environment causes ice to form.

The soda-can effect gets a new name: glaciohydraulic supercooling. In the case of glaciers, this frazil ice forms when meltwater at the glacier bed rushes up a steeply rising slope. The new ice then clogs drainage ways at the glacier bed, dumping sediment, thus reducing the meltwater's (and glacier's) ability to erode. This action is called stabilizing feedback and results in the formation of a new dirty-ice layer along the glacier's underbelly.

"This is new," Larson said. "We're introducing laws of erosion for glaciers, and thus making it easier to understanding how glaciers subdue mountains."

Larson's work at MSU helped to substantiate the theory of glaciohydraulic supercooling – he detected "bomb tritium," an isotope of hydrogen dispersed across the globe in the 1950s and early 1960s during nuclear testing, near the bed of some glaciers.

Under the old model of glacier building, tritium would be expected only near a glacier surface where snow slowly transforms to glacier ice. But Larson showed that tritium can also occur near the glacier's base as the result of recent snowmelt refreezing due to glaciohydraulic supercooling.

In addition to Larson, the paper, "Stabilizing feedbacks in glacier-bed erosion," is authored by Richard Alley of Pennsylvania State University; Daniel Lawson of CRREL; Edward Evenson of Lehigh University in Bethlehem, Pa.; and Gregory Baker of the University of Buffalo.


Story Source:

The above story is based on materials provided by Michigan State University. Note: Materials may be edited for content and length.


Cite This Page:

Michigan State University. "Scientists Rewrite Laws Of Glacial Erosion." ScienceDaily. ScienceDaily, 15 August 2003. <www.sciencedaily.com/releases/2003/08/030814071654.htm>.
Michigan State University. (2003, August 15). Scientists Rewrite Laws Of Glacial Erosion. ScienceDaily. Retrieved September 3, 2014 from www.sciencedaily.com/releases/2003/08/030814071654.htm
Michigan State University. "Scientists Rewrite Laws Of Glacial Erosion." ScienceDaily. www.sciencedaily.com/releases/2003/08/030814071654.htm (accessed September 3, 2014).

Share This



More Earth & Climate News

Wednesday, September 3, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Thousands of Fish Dead in Mexico Lake

Raw: Thousands of Fish Dead in Mexico Lake

AP (Sep. 2, 2014) — Over 53 tons of rotting fish have been removed from Lake Cajititlan in western Jalisco state. Authorities say that the thousands of fish did not die of natural causes. (Sep. 2) Video provided by AP
Powered by NewsLook.com
Raw: Iceland Volcano Spewing Smoke

Raw: Iceland Volcano Spewing Smoke

AP (Sep. 2, 2014) — The alert warning for the area surrounding Iceland's Bardarbunga volcano was kept at orange on Tuesday, indicating increased unrest with greater potential for an eruption. Smoke is spewing from the volcano, and lava is spouting nearby. (Sept. 2) Video provided by AP
Powered by NewsLook.com
U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

Newsy (Sep. 2, 2014) — The U.N. says the problem is two-fold — quarantine zones and travel restrictions are limiting the movement of both people and food. Video provided by Newsy
Powered by NewsLook.com
Halliburton Reaches $1B Gulf Spill Settlement

Halliburton Reaches $1B Gulf Spill Settlement

AP (Sep. 2, 2014) — Halliburton's agreement to pay more than $1 billion to settle numerous claims involving the 2010 BP oil spill could be a way to diminish years of costly litigation. A federal judge still has to approve the settlement. (Sept. 2) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins