The Greenland ice sheet is melting and losing mass at an accelerating rate, and has been doing so since the late 1990s, according to a new study reported in the journal Science and funded by the National Environment Research Council. Scientists who conducted used two different methods--satellite observations and a state-of-the-art regional atmospheric model--to independently confirm the results.
The Greenland ice sheet contains enough water to cause sea levels around the world to rise 7 meters (approximately 23 feet) if all the ice melts. Since 2000, the Greenland ice sheet has lost enough mass to cause an average global sea level increase of about half a millimeter per year--about 5 millimeters total over the past decade.
The scientists attributed the acceleration to a number of causes, including increased melting on the surface of the ice sheet and a higher number of icebergs being produced (and sheared off from the main ice sheet) by Greenland's "fast-flowing outlet glaciers." Warmer-than-usual summers in 2006-2008 also helped to accelerate melting and mass loss on the Greenland ice sheet.
Professor Jonathan Bamber from the University of Bristol, one of the authors of the report, said in a statement: "It is clear from these results that mass loss from Greenland has been accelerating since the late 1990s and the underlying causes suggest this trend is likely to continue in the near future. We have produced agreement between two totally independent estimates, giving us a lot of confidence in the numbers and our inferences about the processes."
A global sea level rise of 5 millimeters over the course of a decade may not seem like much, but consider that in the context of three factors:
- We're talking about adding 5 millimeters to the level of the oceans worldwide, which cover roughly 70 percent of the planet's surface, so that figure actually represents a huge amount of water.
- The 5 millimeter number represents only the sea level increase that can be attributed to water from the Greenland ice sheet since 2000; it doesn't take into account water from other sources or the overall sea level increase for the period.
- Scientists found that the rate at which the Greenland ice sheet is melting and losing mass is accelerating, which means the ice is expected to melt even faster in the years ahead.
Along with threatening island and coastal communities worldwide, rising sea levels also push salt water into rivers and streams, damaging freshwater aquatic species and reducing the amount of fresh water available for drinking and agriculture. And the fresh water released by melting ice changes the acidity and chemical balance of the oceans, creating hazards for saltwater aquatic species that we're only beginning to discover, and reducing the amount of fresh water that exists on Earth.
Photo by Gallo Images/Getty Images
Comments
a) First do the arithmetic before going into a panic:
0.5mm/yr = 5mm/decade = 5cm/century, or 6 centuries to rise 1 ft. Considering the tide can make “sea level” vary by several feet each DAY, what does this really mean?
b) Is there really anything new going on here?:
http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm
http://ocean.dmi.dk/arctic/meant80n.uk.php
What’s new, Guido, is that scientists have confirmed that loss of mass in the Greenland ice sheet is accelerating. So if the ice is melting at an increasingly faster rate, then your arithmetic (straight multiplication) is faulty because it doesn’t account for the escalation that’s going on up north. Not your fault, of course, because you would have to know the rate of acceleration and plot it over time. That’s a tricky thing to do when there are so many variables that can affect the rate at which the ice is melting.
No one is suggesting that the ice sheet will melt away in the next year or two, but the fact that the rate of the melt is picking up speed is cause for concern.
Check the 2nd link I posted: temps are still well below 0degC & only varying cyclically, so any melting is not due to warming air temps.
Here’s the real explanation for the loss of ice: http://wattsupwiththat.com/2009/11/04/arctic-warming-goes-with-the-floe/#more-12488
Just a few inches of ocean rise is extremely dangerous to many coastal communities, including New Orleans, which is already under sea level.
Those few people who say we should do nothing even as the ice is melting, forest fires are raging, and we continue to see records set for extreme weather conditions all around the globe, make no sense.
If they are right, but we act as if there is a crisis, we will still have worked to end the production energy from sources that are polluting our world in all the traditional ways. We will all breathe easier.
If they are wrong, by acting now we will reduce the tremendous consequences that are predicted.
Acting now is a win win.
In any case, the overwhelming scientific evidence shows that we are faced with real danger in the short run and potential calamity in the long run. It would be suicidal to bet against this evidence.
Some people sleep better by living in denial. I sleep better knowing the truth so I can help fight for a better future.
Gentlemen below please find a letter that I sent to my local center specializing in Recycling Science. However, please be my guest in sending out this letter to other Industries charged with the same function.
Thank You
____________________________________________________________________
Advanced Recycling Sciences, Inc.
2030 Main St. Ste. 1300
Irvine, CA
92614
United States
Dear Staff,
Due to the dire straits of our planet and what seems to be a generalized apathy with improving Recycling Technology; I would like to pose a question or, rather more of a challenge.
As I understand it the main hindrance with making Plastic Recycling (specifically with bottles and containers) unprofitable and labor intensive is the following:
Plastic recycling rates lag far behind those of other items, such as newspaper (about 80%) and corrugated fiberboard (about 70%). Low national plastic recycling rates have been due to the complexity of sorting and processing, unfavorable economics, and consumer confusion about which plastics can actually be recycled Part of the confusion has been due to the recycling symbol that is usually on all plastic items
This symbol is called a resin identification code. It is stamped or printed on the bottom of containers and surrounded by a triangle of arrows. The intent of these arrows was to make it easier to identify plastics for recycling. The recycling symbol doesn’t necessarily mean that the item will be accepted by residential recycling programs. They just indicate the plastic resin content.
Now since items slated for recycling must be sorted by hand per resin identification code this makes the process labor intensive and not cost effective. Thus the landfills grower even greater and the oceans even filthier.
It would seem to me that the hold-up in making recycling a viable option could be solved very easily, that is, if scientific minds were directed to do such. For instance, what if already existing scientific apparatuses were slightly modified to address identification in an automated fashion. Let me suggest for starters, The Spectrometer. I assume that you will take the initiative to survey the current uses of The Spectrometer. I am sure it can be modified to scan and detect, if not the component of the material itself than at least some embedded element included in the production process of such containers. Countries that import such container would be held to a more ecological standard by having such innovations.
But don’t stop there. There are probably a host of scientific apparatuses that could meet or even exceed the Spectrometer that I don’t even have knowledge of. Please gentlemen, exert yourselves, our future depends on it.
I am sure that you will not forget the catalysis and the source of this challenge.
Phillip Ghee
Phillipghee@yahoo.com
It seems the assumption is that the rate of melting will increase, however, I have read other articles stating that once the outflows over the water melt the landlocked portion of the ice will not continue to melt due to the natural affect of the water under the ice. I am no scientist but that seems to be a sustainable point given the air temperatures have been relatively constant with not more than average fluctuations over time. I don’t think it is a mere coincidence the headlines blare ice sheets melting acceleration in Greenland just prior to the Copenhagen meetings. One has to really dig into the story to find it is outlet glaciers and that it is a near term issue in terms of the acceleration so what the author and the journalists really want you to take away is the headline and think OMG we need to so something!!!
Just one mans opinion.
Oh, and why not abandon New Orleans or rebuild it in an area that is above sea level and sustainable. Oh there is that sustainable word which should only be used with energy or some green idea. Civilizations have always abandoned cities which became unlivable because of changes be they climate or other wise. Only modern man insists on living in an area below sea level and spending the billions of dollars required to make it a habitat for man. Ridiculous.
*** I have read other articles stating that once the outflows over the water melt the landlocked portion of the ice will not continue to melt due to the natural affect of the water under the ice.***
But landlocked portions have no water under it. It’s on land. Right? Or am I missing something?
And as for *** I am no scientist but that seems to be a sustainable point given the air temperatures have been relatively constant with not more than average fluctuations over time.***
There has been a verified increase in temperatures throughout the Arctic. Permafrost is melting- or is that caused by currents, too?