The effect of climate change on iceberg production by Greenland glaciers

May 08, 2013
Isua Supracrustal Belt Isua, south-west Greenland. Credit: University of Washington.

While the impact of climate change on the surface of the Greenland ice sheet has been widely studied, a clear understanding of the key process of iceberg production has eluded researchers for many years. Published in Nature this week, a new study presents a sophisticated computer model that provides a fresh insight into the impact of climate change on the production of icebergs by Greenland glaciers, and reveals that the shape of the ground beneath the ice has a strong effect on its movement.

Over the past decade, ice-loss from the has been accelerating, raising concerns about runaway losses and consequent sea-level rise. But research into the four major Greenland fast-flowing glaciers has enabled scientists to show that while these glaciers may show several bursts of retreat and periods of high iceberg formation in future, the rapid acceleration seen in recent years is unlikely to continue unchecked.

This is a crucial step forward in understanding how Greenland's glaciers will contribute to sea-level rise in the future and indicates, say the scientists, how important a more detailed knowledge of such glaciers is. The scientists first investigated the current behaviour of the four glaciers and found that the rate at which they lose ice depends critically on the shape of the fjords in which they sit, and the topography of the rock below them.

A for fast-flowing was then specifically designed from their investigations. It gave a projected sea-level-rise contribution from these glaciers of 2cm to 5cm by the year 2200, which is lower than estimates based solely on the of current trends.

Lead author Dr Faezeh Nick, of the Université Libre de Bruxelles, says,

"I am excited by the way we have managed to create a detailed picture of the workings of the glaciers. It turns out that if the fjord a glacier sits in is wide or narrow it really affects the way the glacier reacts. The important role of the terrain below the ice shows we need to get a much clearer picture of the rest of Greenland's glaciers before we have the whole story."

The scientists chose the four glaciers, Petermann, Kangerdlugssuaq, Helheim and Jakobshavn Isbræ, as together these drain around 20 per cent of the Greenland ice sheet. The model, which was developed within the EU funded ice2sea programme, predicts that, together these glaciers will lose on average, 30Gt of ice per year to 47Gt per year over the 21st century. A Gigaton (Gt) is the equivalent of 1 cubic kilometre (km3) of water. For comparison Lake Geneva contains about 90Gt of water.

Professor David Vaughan, who works at the British Antarctic Survey in Cambridge and is head of the ice2sea programme says,

"We know that the breaking off of icebergs from glaciers is influenced by climate, but this is the first time we've been able make projections of how the most important in Greenland will be affected by future . The ice2sea research led by Dr Nick shows how a truly international programme can make it possible for scientists to work together across different institutions to make significant steps forward."

Explore further: NASA sees Hurricane Edouard far from US, but creating rough surf

More information: "Future sea-level rise from Greenland's major outlet glaciers in a warming climate" by Faezeh Nick et al is published on May 9 in Nature. dx.doi.org/10.1038/nature12068

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mememine69
1.4 / 5 (19) May 08, 2013
Former climate blame believers are better planet lovers: Science never lied or committed a hoax, it was you believers and politicians and lazy copy and paste news editors that had exaggerated the science itself.


"Help my planet could possibly be on fire maybe?"

After 28 years of research the scientists still refuse to say their CO2 crisis is as real as they like to say asteroid hits are; inevitable and eventual or WILL happen not just might and could and maybe and…..
28 years of "maybe" proves it won't be a crisis.
So how close to unstoppable warming will science lead us before they finally would say it WILL happen not just might happen.

Occupywallstreet does not even mention CO2 in its list of demands because of the bank-funded and corporate run carbon trading stock markets ruled by corporations.
djr
4.5 / 5 (15) May 08, 2013
"So how close to unstoppable warming will science lead us before they finally would say it WILL happen not just might happen."

They probably will never say it WILL happen - that seems common sense to me. You have a highly complex system - you recognize that you do not understand all of the components of this system, and your modeling is still relatively crude compared to the overall complexity. So of course you are not able to declare certainties regarding the future. In Oklahoma - there is a 70% chance of rain tmrw. Does that make meteorology irrelevant, or just functioning within certain tollerance?

Why do you need to keep repeating the same thing over and over - despite other posters trying to address your rubbish? Oh - you are just trolling!!!!!
The Alchemist
1 / 5 (15) May 09, 2013
I'm a scientist, I'll say it will happen. In fact, is happening. God isn't going to just turn on a green light you know.
Keep in mind Greenland is a very interesting study, possibly the least dynamic ice body, supported/protected by stone in the N Hemisphere.
PS You'll notice 'scientists' are talking less and less about CO2 (and NOT in this article), and fairly casual research will reveal a trend against it being the causal agent.
None-the-less the primary observable of the wretchedly named "Global WARMING" is the melting of glacial and polar ice, and we've observed plenty of loss.
VendicarE
4.6 / 5 (9) May 09, 2013
I had no idea that Alchemy, Phrenology and general Kookery constituted a science.

"I'm a scientist," - Alchemist
VendicarE
4.4 / 5 (9) May 09, 2013
Only 28 years?

"After 28 years of research the scientists still refuse to say" - YouYouTard

You don't honestly think that scientists have been studying climate for only 28 years do you?

Is there some central clearing house that you Anti-Science Morons get your disinformation?
Neinsense99
3 / 5 (12) Jun 05, 2013
I find the pejorative "YouYouTard" unsightly. Have you tried MeMeMindless instead?
antigoracle
1 / 5 (13) Jun 05, 2013
Only 28 years?

"After 28 years of research the scientists still refuse to say" - YouYouTard

You don't honestly think that scientists have been studying climate for only 28 years do you?

Is there some central clearing house that you Anti-Science Morons get your disinformation?
-- VendicarEturd
Wow, just wow!! You take stupidity to an art form. Thanks for making our case.
Neinsense99
3 / 5 (12) Jun 05, 2013
Only 28 years?

"After 28 years of research the scientists still refuse to say" - YouYouTard

You don't honestly think that scientists have been studying climate for only 28 years do you?

Is there some central clearing house that you Anti-Science Morons get your disinformation?
-- VendicarEturd
Wow, just wow!! You take stupidity to an art form. Thanks for making our case.

Proving once again that bile is not content.
antigoracle
1 / 5 (14) Jun 05, 2013
Only 28 years?

"After 28 years of research the scientists still refuse to say" - YouYouTard

You don't honestly think that scientists have been studying climate for only 28 years do you?

Is there some central clearing house that you Anti-Science Morons get your disinformation?
-- VendicarEturd
Wow, just wow!! You take stupidity to an art form. Thanks for making our case.

Proving once again that bile is not content.

Confirming ad infinitum what stupidity is.