UA Fairbanks Researcher - Greenland Ice Sheet Runoff To More Than Double By 2100

[hatrack]

Mods: Press release

FOR IMMEDIATE RELEASE
June 11, 2008

The Greenland Ice Sheet is melting faster than previously calculated according to a scientific paper by University of Alaska Fairbanks researcher Sebastian H. Mernild published recently in the journal “Hydrological Processes.”

The study is based on the results of state-of-the-art modeling using data from the Intergovernmental Panel on Climate Change as well as satellite images and observations from on the ground in Greenland.

Mernild and his team found that the total amount of Greenland Ice Sheet freshwater input into the North Atlantic Ocean expected from 2071 to 2100 will be more than double what is currently observed. The current East Greenland Ice Sheet freshwater flux is 257 km3 per year from both runoff and iceberg calving. This freshwater flux is estimated to reach 456 km3 by 2100.

Mernild’s results further show a change in total East Greenland freshwater flux from today’s values of 438 km3 per year to 650 km3 per year by 2100. This indicates an increase in global sea level rise estimates from 1.1 millimeters per year to 1.6 millimeters per year.

“The Greenland Ice Sheet mass balance is changing as a response to the altered climatic state,” said Mernild. “This is faster than expected. This affects freshwater runoff input to the North Atlantic Ocean, and plays an important role in determining the global sea level rise and global ocean thermohaline circulation.”

Mernild is conducting the research as part of the University of Alaska’s International Polar Year efforts. He was appointed a University of Alaska IPY postdoctoral fellow by UA president Mark Hamilton in 2007.

For more information contact Jenn Wagaman at 907-474-5082 or [e-mail] or Sebastian Mernild at [e-mail].

About IPY
The Polar regions have profound significance for the Earth's climate and environments, ecosystems and human society. IPY is an interdisciplinary and internationally coordinated research campaign, ushering in a new era of polar science. For more information on IPY, visit http://www.ipy.alaska.edu

EDIT/END

http://www.alaska.edu/ipy/press/stories/mernild.xml

[GliderGuider]

1. "faster than previously calculated" -- that's a nice variation on the usual phrase!

Very scientific-sounding, too.

[RaleighNCDUer]

2. A very optimistic report.

I personally expect to see the Greenland ice sheet gone by 2100 (should I live to be 150).

With summer polar ice completely gone within 10 years the polar warming feedback will increase melting at a geometric rate. As water levels rise, coastal ice will float, and float away, speeding the movement of ice to the sea.

I have, of course, no data to back me up, but look at the predictions over the past 20 years. In virtually every case you can take the prediction and quadruple the effects, and come close to the reality. Just five years ago they were saying the summer polar sea ice might be all gone by 2050. Now, it looks like it won't last past 2015 at the best.

There are just too many disparate feedback loops to be figured in - reduced albedo, melting of the permafrost, release of frozen methane deposits, freshwater dilution of the ocean, slowing of the thermohaline circulation. Every one of those affects all the others - not to mention the things that we don't really know about yet. How will the warming affect the jet stream? And how will the jet stream affect the warming? Will there be more, or less cloud cover?

It's going to be a bumpy century.

[Vogon_Glory]

6. Apology From The Baby-Boomers: We Screwed Up

In years past, I took comfort from the fact that most of the people obstructing the creation of a better world were of World War II vintage and older. I was sure that we baby boomers would do better after the older guys passed on.

I can no longer do this. I've noticed that the people most responsible for maintaining the fossil fuel threat to ecosystems worldwide are my fellow baby-boomers. We're the guys most responsible for denying our posterity a decent, dignified, livable future.

To those who inherit the planet and biosphere after we kick off: Sorry, guys, we screwed up.

:dunce:

:hurts:

[tom_paine]

3. This almost certainly mean it will triple or quadruple by then.

Not that I am impugning the integrity of these AK researchers, but merely to make a statement of fact.

Most times, in science, and especially climate sicence, I would think, that scientists are often as conservative (I am not speaking in the political sense) in their estimates as possible, to avoid being discredited later on if aggressive prediction don't come true.

Normally, this is a good thing and a function ofthe thoroughness of the Scientific Method. When I worked in research science, often we would get together at a monthly roundtable to examine everyone's data and conclusions, then do our level best to attack and disprove them.

The reasoning being to strengthen our own conclusions, to anticipate where thing may have gone wrong, or mistaken assumption or reading of the data that could later invalidate said conclusions.

Better to figure it out among friends than enemies, so to speak.

In any case, this natural outgrowth ofthe scientific method also means on the are occasion when thing are spiralling out of control in a positive feedback loop, it is almost always true that the scientific predictions based on current data lag behind.

I mean, look at the IPPC report. It's "worst case" (most aggressive) predictions were outstripped almost before the ink was dry on the firsdt printing. Now, to see the data since the IPCC report, it's clear that their "worst case" predictions were actually the "best case" predictions and their "best case" predictions now laughably, woefully irrelevant and fantastic for being way too conservative.

I suspect similar forces are at work with this research, too.

[Bigmack]

4. Not much international comment that I've seen on

that little detail about the Greenland ice sheet's melting which "plays an important role in determining the global sea level rise and global ocean thermohaline circulation.” Hmmmmm....... More fresh water 'up there in the north'.....the warm salt water sinking sooner, further to the south...... I'd call THAT potential CATASTROPHE! Ms Bigmack

[DCKit]

5. There's already been a huge increase...

and it's growing exponentially. We don't have 92 years to contemplate this problem.