Featured Research

from universities, journals, and other organizations

Miniature Lab Ice Spikes May Hold Clues To Warming Impacts On Glaciers

Date:
March 6, 2007
Source:
University of Colorado at Boulder
Summary:
Tiny lab versions of 12-foot tall snow spikes that form naturally on some high mountain glaciers may someday help scientists mitigate the effects of global warming in the Andes, according to a University of Colorado at Boulder professor.

Ice penitentes in Andes.
Credit: Image courtesy Javier Corripio, Federal Institute of Technology, Zurich

Tiny lab versions of 12-foot tall snow spikes that form naturally on some high mountain glaciers may someday help scientists mitigate the effects of global warming in the Andes, according to a University of Colorado at Boulder professor.

CU-Boulder physics Assistant Professor Meredith Betterton said the spikes, known as penitentes, are shaped when concentrated rays of sunlight evaporate snow from low spots on glacier fields in a process known as sublimation. The lab studies confirm that the low spots, or troughs, deepen as intense sunlight strikes them, sculpting penitentes by the hundreds of thousands on some glaciers, she said.

Some scientists have predicted that penitentes might help put the brakes on shrinking glaciers in a warming climate by blocking sunlight that might otherwise be absorbed by glacial surfaces, said Betterton. She gave a presentation on penitentes at the March Meeting of the American Physical Society in Denver March 5-9, which hosted more than 7,000 scientists.

"The key piece of physics here is that the dips in the snow absorb more reflected light, which drops the snow height and helps to form the penitentes," she said. "One big question is how penitentes will fare in a warming world."

Betterton, along with colleagues Vance Bergeron and Charles Berger from Ecole Normale Superieure research laboratories in Paris, sprouted miniature penitentes in the lab to better understand the physics behind their formation. Penitentes -- named for their resemblance to a procession of white-hooded monks -- were first described by naturalist Charles Darwin during an expedition to South America he and his crew made in 1835 aboard his ship, the Beagle.

The research team put a block of snow in a horizontal freezer in Paris filled with water vapor and chilled with liquid nitrogen, covered it with a clear Plexiglas lid, and shined a spotlight on the snow to simulate sunlight, Betterton said. Tiny snow spikes up to two inches high formed within a few hours, apparently by the same process through which penitentes form naturally on alpine glaciers, she said.

The study confirmed previous theories that penitentes grow when sunlight in cold, dry air in the high mountains strikes snow patches and transforms them directly into water vapor, she said. Mathematical models developed by Betterton indicate microscopic penitentes begin merging with each other, or "coarsening," early in the sublimation process, growing both taller and wider over time.

The research has applications for understanding and even mitigating global warming, since Andean penitentes shade large areas of glacial surfaces, possibly cooling them and slowing the rate of ice loss, she said. Some scientists believe warming temperatures could trigger the eventual destruction of vast fields of penitentes and hasten glacier melting, "which would be disastrous for Argentinean and Chilean regions that depend on runoff for water supplies," said Betterton.

Betterton and her colleagues took the research a step further, sprinkling the sprouting lab penitentes with a fine layer of carbon soot to simulate pollutants known to be accumulating on some glaciers around the globe. Such carbon-based pollutants have been found to increase melting rates on glaciers by causing the ice to absorb more sunlight and heat up, she said.

The team found that small amounts of soot sprinkled on the snow in the lab appeared to accelerate penitente formation. "One worry that scientists have is that without penitentes, some of these Andean glaciers will melt more quickly," she said. "It may well be that adding a small layer of dirt to the surface of these glaciers could help to preserve them."

The penitente research effort also has implications for the microelectronic industry, she said. Precisely shaped micro-penitentes formed by laser beams could lead to the development of solar energy cells that trap light more efficiently.

Betterton's research has been funded in part by the Alfred P. Sloan Foundation.


Story Source:

The above story is based on materials provided by University of Colorado at Boulder. Note: Materials may be edited for content and length.


Cite This Page:

University of Colorado at Boulder. "Miniature Lab Ice Spikes May Hold Clues To Warming Impacts On Glaciers." ScienceDaily. ScienceDaily, 6 March 2007. <www.sciencedaily.com/releases/2007/03/070305140922.htm>.
University of Colorado at Boulder. (2007, March 6). Miniature Lab Ice Spikes May Hold Clues To Warming Impacts On Glaciers. ScienceDaily. Retrieved September 19, 2014 from www.sciencedaily.com/releases/2007/03/070305140922.htm
University of Colorado at Boulder. "Miniature Lab Ice Spikes May Hold Clues To Warming Impacts On Glaciers." ScienceDaily. www.sciencedaily.com/releases/2007/03/070305140922.htm (accessed September 19, 2014).

Share This



More Earth & Climate News

Friday, September 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Wildfires in CA Burn Forest Asunder

Raw: Wildfires in CA Burn Forest Asunder

AP (Sep. 18, 2014) An out-of-control Northern California wildfire has nearly 2,800 people from their homes as it continues to grow, authorities said Thursday. Authorities said a man has been arrested on suspicion of arson for starting the fire on Saturday. (Sept. 18) Video provided by AP
Powered by NewsLook.com
Raw: Elephant Undergoes Surgery in Tbilisi Zoo

Raw: Elephant Undergoes Surgery in Tbilisi Zoo

AP (Sep. 18, 2014) Grand the elephant has successfully undergone surgery to remove a portion of infected tusk at Tbilisi Zoo in Georgia. British veterinary surgeons used an electric drill to extract the infected piece. (Sept. 18) Video provided by AP
Powered by NewsLook.com
Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Man Floats for 31 Hours in Gulf Waters

Man Floats for 31 Hours in Gulf Waters

AP (Sep. 16, 2014) A Texas man is lucky to be alive after he and three others floated for more than a day in the Gulf of Mexico when their boat sank during a fishing trip. (Sept. 16) 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