Featured Research

from universities, journals, and other organizations

Alpine glacier, unchanged for thousands of years, now melting: New ice cores suggest Alps have been strongly warming since 1980s

Date:
December 11, 2013
Source:
Ohio State University
Summary:
Less than 20 miles from the site where melting ice exposed the 5,000-year-old body of Ötzi the Iceman, scientists have discovered new and compelling evidence that the Italian Alps are warming at an unprecedented rate. Part of that evidence comes in the form of a single dried-out leaf from a larch tree that grew thousands of years ago.

This 2,600-year-old larch leaf was found buried in ice atop Mt. Ortles in Italy.
Credit: Image courtesy of Ohio State University

Less than 20 miles from the site where melting ice exposed the 5,000-year-old body of Ötzi the Iceman, scientists have discovered new and compelling evidence that the Italian Alps are warming at an unprecedented rate.

Part of that evidence comes in the form of a single dried-out leaf from a larch tree that grew thousands of years ago.

A six-nation team of glaciologists led by The Ohio State University drilled a set of ice cores from atop Mt. Ortles in northern Italy, and described their early findings on Monday, Dec. 9 at the American Geophysical Union meeting in San Francisco.

The Alto dell'Ortles glacier, which did not show signs of melting for thousands of years, now appears to be shifting away from a constantly below-freezing state to one where its upper layers are at the melting point throughout the year, said project leader Paolo Gabrielli, research scientist at Byrd Polar Research Center at Ohio State.

"Our first results indicate that the current atmospheric warming at high elevation in the Alps is outside the normal cold range held for millennia," he said. "This is consistent with the rapid, ongoing shrinking of glaciers at high elevation in this area."

As they drilled into the glacier in 2011, Gabrielli and his team discovered that the first 100 feet (about 30 meters) of the glacier was composed of "firn" -- grainy, compacted snow that had partly melted. Below that, they found nothing but solid and colder ice all the way down to the frozen bedrock.

That suggests that snow was accumulating on the mountaintop and was compacted into ice for thousands of years without ever melting -- until about 30 years ago, which is when each year's new deposit of snow began melting.

The researchers know that the glacier had previously remained unchanged for a very long time -- in part because of the preserved larch leaf, which they found wedged into the ice well beyond the firn layer, around 240 feet beneath the surface and encased in solid ice. They identified the leaf as belonging to Larix decidua, or the European larch.

Carbon dating determined it to be around 2,600 years old. That means that Ötzi had already been dead for more than two millennia when this particular larch tree grew, though it was not far from his resting place.

"The leaf supports the idea that prehistoric ice is still present at the highest elevations of the region," Gabrielli said.

The researchers are just beginning to chemically analyze the ice cores they retrieved. Trace metals and dust sealed in the ice will give more detailed clues to the climatic conditions when the ice was formed.

Gabrielli added that the cores are unique in the European Alps, because the winter and summer layers of ice accumulation are easily identifiable, offering the promise of a high-resolution climate record.

Of particular interest to the researchers is why temperatures in the Alps are increasing at twice the global rate. As the highest glacier in the eastern Alps (2.4 miles, or 3.9 km, above sea level), Alto dell'Ortles is located in the heart of Europe -- one of the most industrialized and populated areas of the world. The team will investigate whether soot emitted by human activities in central and southern Europe plays a role -- perhaps by darkening the surface of the glacier, absorbing the sun's heat and melting ice.

"Ortles offers us the unique possibility to closely verify if and how regional environmental changes can interact with climatic changes of global significance," Gabrielli said.

His Ohio State colleagues on the project included Lonnie Thompson and Mary Davis. International collaborators hailed from: University of Venice, Accademia Nazionale dei Lincei, Provincia Autonoma di Bolzano, Waterstones Geomonitoring, University of Padua, University of Pavia and University of Trieste, all of Italy; the Russian Academy of Sciences in Moscow; the University of Innsbruck, Austria; and the University of Bern, Switzerland.

This work was partly funded by the National Science Foundation.


Story Source:

The above story is based on materials provided by Ohio State University. The original article was written by Pam Frost Gorder. Note: Materials may be edited for content and length.


Cite This Page:

Ohio State University. "Alpine glacier, unchanged for thousands of years, now melting: New ice cores suggest Alps have been strongly warming since 1980s." ScienceDaily. ScienceDaily, 11 December 2013. <www.sciencedaily.com/releases/2013/12/131211132447.htm>.
Ohio State University. (2013, December 11). Alpine glacier, unchanged for thousands of years, now melting: New ice cores suggest Alps have been strongly warming since 1980s. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2013/12/131211132447.htm
Ohio State University. "Alpine glacier, unchanged for thousands of years, now melting: New ice cores suggest Alps have been strongly warming since 1980s." ScienceDaily. www.sciencedaily.com/releases/2013/12/131211132447.htm (accessed October 22, 2014).

Share This



More Earth & Climate News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Traditional Farming Methods Gaining Ground in Mali

Traditional Farming Methods Gaining Ground in Mali

AFP (Oct. 20, 2014) — He is leading a one man agricultural revolution in Mali - Oumar Diatabe uses traditional farming methods to get the most out of his land and is teaching others across the country how to do the same. Duration: 01:44 Video provided by AFP
Powered by NewsLook.com
How Detroit's Money Woes Led To U.N.-Condemned Water Cutoffs

How Detroit's Money Woes Led To U.N.-Condemned Water Cutoffs

Newsy (Oct. 20, 2014) — The United Nations says water is a human right, but should it be free? Detroit has cut off water to residents who can't pay, and the U.N. isn't happy. Video provided by Newsy
Powered by NewsLook.com
Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

3BL Media (Oct. 20, 2014) — Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-fuel Impala Video provided by 3BL
Powered by NewsLook.com
White Rhino's Death In Kenya Means Just 6 Are Left

White Rhino's Death In Kenya Means Just 6 Are Left

Newsy (Oct. 20, 2014) — Suni, a rare northern white rhino at Ol Pejeta Conservancy, died Friday. This, as many media have pointed out, leaves people fearing extinction. Video provided by Newsy
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:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

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