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| -Signs, Portents, and the Weather- |
| Greenland's Glaciers Take a Breather |
| 2007-02-10 |
| (forgot to carry the two. sorry.) It was big news when the rate of melting suddenly doubled in 2004 as ice sheets began moving more quickly into the sea. That inspired predictions of the imminent demise of Greenland's ice — and a catastrophic rise in sea level. But a paper published online this afternoon by Science reports that two of the largest glaciers have suddenly slowed, bringing the rate of melting last year down to near the previous rate. At one glacier, Kangerdlugssuaq, "average thinning over the glacier during the summer of 2006 declined to near zero, with some apparent thickening in areas on the main trunk." Trust me, using one year as a dataset for long term predictions is the gold standard for this type of analysis. I asked the lead author of the paper, Ian Howat of the University of Washington, for some perspective. Here's his take: "Over the past few years there has been a major revolution in the way scientists think about ice sheet response to climate change. Previously, it was assumed that the big ice sheets react very slowly to climate, on the order of centuries to millenia. This is because surface melting and precipitation was thought to be the dominant way in which ice sheets gain and lose mass under changes in climate. However, over the past five years we have observed that the flow speed of the ice sheets, and therefore the rate at which the ice flows to ocean can change dramatically over very short time scales." You mean that weather can get colder too? By short, he means months or less. I also asked Dr. Howat about the argument that, since Greenland went through decades of relatively warm weather in the first half of the 20th century without catastrophic consequences, it's unlikely that the glaciers are suddenly going to plunge into the ocean because of the current warming. His response: I can't believe these global warming deniers are actually using historical weather data to argue against the obvious looming disaster. Who do they think they are? Scientists? "Greenland was about as warm or warmer in the 1930's and 40's, and many of the glaciers were smaller than they are now. This was a period of rapid glacier shrinkage world-wide, followed by at least partial re-expansion during a colder period from the 1950's to the 1980's. Of course, we don't know very much about how the glacier dynamics changed then because we didn't have satellites to observe it. However, it does suggest that large variations in ice sheet dynamics can occur from natural climate variability. The problem arises in the possibility that, due to anthropogenic warming, warm phases will become longer and more severe, so that each time the glaciers go through a period of retreat like this, they won't fully grow back and they will retreat farther the next time." That sounds like a reasonable concern. But for now, with the glaciers moving in fits and starts, it's wise not to make any sweeping predictions based on a few measurements. Although the Intergovernmental Panel on Climate Change was criticized for not incorporating the recent scary data from Greenland into its long-range projections, these new results seem to vindicate its caution. As Dr. Howat and his co-authors warn: "Special care must be taken in how these and other mass-loss estimates are evaluated, particularly when extrapolating into the future because short-term spikes could yield erroneous long-term trends." Keep trying to use you magic science. Deny it all you want. You can't fool the people. The revolution will not be televised. |
| Posted by:Danking70 |
| #7 I read an article at CO2Science several months ago where someone had done a carbon-14 test on some tundra bog on the east coast of Greenland that showed temperatures in the Midieval warm period at that location were 20 or more degrees warmer than they are today. Those da$$$$ Vikings and their SUVs! |
| Posted by: Old Patriot 2007-02-10 18:49 |
| #6 Let me know when it's warm enough for another Norse colony. |
| Posted by: DMFD 2007-02-10 11:33 |
| #5 Infidels! Your blasphemy will not stand! Cut out their tongues and behead them! |
| Posted by: "Dr" Heidi Cullen 2007-02-10 11:11 |
| #4 Is China going to be iced over anytime soon? if not, shut up and go away with your alarmist Crap. |
| Posted by: Redneck Jim 2007-02-10 09:23 |
| #3 "Greenland was about as warm or warmer in the 1930's and 40's, and many of the glaciers were smaller than they are now. This was a period of rapid glacier shrinkage world-wide, followed by at least partial re-expansion during a colder period from the 1950's to the 1980's. Speaking in a scientific manner about global warming the historic data indicate clearly that we should rapidly and violently complete the hot war with the Caliphate and enter into the cold war with China. |
| Posted by: Nimble Spemble 2007-02-10 08:23 |
| #2 The problem arises in the possibility that, due to anthropogenic warming, warm phases will become longer and more severe, This is Greenland they are talking about. How can a little warming be severe? |
| Posted by: phil_b 2007-02-10 06:04 |
| #1 D ***ng, can't be - see C2CAM Show or Website for segment wid Lawrence Joseph. |
| Posted by: JosephMendiola 2007-02-10 00:28 |