Featured Research

from universities, journals, and other organizations

Greenland ice sheet may melt completely with 1.6 degrees of global warming

Date:
March 12, 2012
Source:
Potsdam Institute for Climate Impact Research (PIK)
Summary:
The Greenland ice sheet is likely to be more vulnerable to global warming than previously thought. The temperature threshold for melting the ice sheet completely is in the range of 0.8 to 3.2 degrees Celsius of global warming, with a best estimate of 1.6 degrees above pre-industrial levels, shows a new study.

Near Greenland. The Greenland ice sheet is likely to be more vulnerable to global warming than previously thought. The temperature threshold for melting the ice sheet completely is in the range of 0.8 to 3.2 degrees Celsius of global warming, with a best estimate of 1.6 degrees above pre-industrial levels, shows a new study. Today, already 0.8 degrees global warming has been observed.
Credit: © Martin Schwan / Fotolia

The Greenland ice sheet is likely to be more vulnerable to global warming than previously thought. The temperature threshold for melting the ice sheet completely is in the range of 0.8 to 3.2 degrees Celsius of global warming, with a best estimate of 1.6 degrees above pre-industrial levels, shows a new study by scientists from the Potsdam Institute for Climate Impact Research (PIK) and the Universidad Complutense de Madrid. Today, already 0.8 degrees of global warming has been observed. Substantial melting of land ice could contribute to long-term sea-level rise of several meters and therefore it potentially affects the lives of many millions of people.

Related Articles


The time it takes before most of the ice in Greenland is lost strongly depends on the level of warming. "The more we exceed the threshold, the faster it melts," says Alexander Robinson, lead-author of the study now published in Nature Climate Change. In a business-as-usual scenario of greenhouse-gas emissions, in the long run humanity might be aiming at 8 degrees Celsius of global warming. This would result in one fifth of the ice sheet melting within 500 years and a complete loss in 2000 years, according to the study. "This is not what one would call a rapid collapse," says Robinson. "However, compared to what has happened in our planet's history, it is fast. And we might already be approaching the critical threshold."

In contrast, if global warming would be limited to 2 degrees Celsius, complete melting would happen on a timescale of 50.000 years. Still, even within this temperature range often considered a global guardrail, the Greenland ice sheet is not secure. Previous research suggested a threshold in global temperature increase for melting the Greenland ice sheet of a best estimate of 3.1 degrees, with a range of 1.9 to 5.1 degrees. The new study's best estimate indicates about half as much.

"Our study shows that under certain conditions the melting of the Greenland ice sheet becomes irreversible. This supports the notion that the ice sheet is a tipping element in the Earth system," says team-leader Andrey Ganopolski of PIK. "If the global temperature significantly overshoots the threshold for a long time, the ice will continue melting and not regrow -- even if the climate would, after many thousand years, return to its preindustrial state." This is related to feedbacks between the climate and the ice sheet: The ice sheet is over 3000 meters thick and thus elevated into cooler altitudes. When it melts its surface comes down to lower altitudes with higher temperatures, which accelerates the melting. Also, the ice reflects a large part of solar radiation back into space. When the area covered by ice decreases, more radiation is absorbed and this adds to regional warming.

The scientists achieved their insights by using a novel computer simulation of the Greenland ice sheet and the regional climate. This model performs calculations of these physical systems including the most important processes, for instance climate feedbacks associated with changes in snowfall and melt under global warming. The simulation proved able to correctly calculate both the observed ice-sheet of today and its evolution over previous glacial cycles, thus increasing the confidence that it can properly assess the future. All this makes the new estimate of Greenland temperature threshold more reliable than previous ones.


Story Source:

The above story is based on materials provided by Potsdam Institute for Climate Impact Research (PIK). Note: Materials may be edited for content and length.


Journal Reference:

  1. Alexander Robinson, Reinhard Calov, Andrey Ganopolski. Multistability and critical thresholds of the Greenland ice sheet. Nature Climate Change, 2012; DOI: 10.1038/NCLIMATE1449

Cite This Page:

Potsdam Institute for Climate Impact Research (PIK). "Greenland ice sheet may melt completely with 1.6 degrees of global warming." ScienceDaily. ScienceDaily, 12 March 2012. <www.sciencedaily.com/releases/2012/03/120312003232.htm>.
Potsdam Institute for Climate Impact Research (PIK). (2012, March 12). Greenland ice sheet may melt completely with 1.6 degrees of global warming. ScienceDaily. Retrieved March 31, 2015 from www.sciencedaily.com/releases/2012/03/120312003232.htm
Potsdam Institute for Climate Impact Research (PIK). "Greenland ice sheet may melt completely with 1.6 degrees of global warming." ScienceDaily. www.sciencedaily.com/releases/2012/03/120312003232.htm (accessed March 31, 2015).

Share This


More From ScienceDaily



More Earth & Climate News

Tuesday, March 31, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

You Won't Be Driving Tesla's Mystery Product

You Won't Be Driving Tesla's Mystery Product

Newsy (Mar. 30, 2015) — Tesla CEO Elon Musk announced a new product line will debut April 30, but it&apos;s not a car. Video provided by Newsy
Powered by NewsLook.com
Solar Impulse Departs Myanmar for China

Solar Impulse Departs Myanmar for China

AFP (Mar. 30, 2015) — Solar Impulse 2 takes off from Myanmar&apos;s second biggest city of Mandalay and heads for China&apos;s Chongqing, the fifth flight of a landmark journey to circumnavigate the globe powered solely by the sun. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
Colombian Project Transforms Old Tires Into Green Housing

Colombian Project Transforms Old Tires Into Green Housing

AFP (Mar. 30, 2015) — To put a roof over their heads and help the environment, residents near Bogota are building houses out of recycled bottles and old tires. Duration: 01:10 Video provided by AFP
Powered by NewsLook.com
The Future Of Japanese Whaling: Heritage Vs. Conservation

The Future Of Japanese Whaling: Heritage Vs. Conservation

Newsy (Mar. 30, 2015) — In 2014, the International Court of Justice ruled Japan could no longer engage in whaling in the Antarctic, but Japan has plans to return this year. 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