The 400-meter decrease in thickness at the NEEM site reported by the scientists, for example, included a range of plus or minus 250 meters. The finding that the surface elevation was 130 meters below the present included a range of plus or minus 300 meters.
"I don't think they should have reached any conclusion about how much the ice sheet shrank," added Kurt Cuffey, a professor at the University of California, Berkeley, noting the "uncertainties" in the number ranges. The high end of the range for reduction in ice thickness is "very large," he said.
Additionally, Greenland still will be the biggest contributor to sea level rise in the immediate future, despite Antarctica's ultimate role, according to Dahl-Jensen. A study in November in Science found that Greenland has experienced more dramatic melting than Antarctica since the 1990s (ClimateWire, Nov. 30, 2012).
Dahl-Jensen noted that a fraction of the sea level rise seen in the Eemian, 1 meter, would still create major problems for coastal areas. Many scientists think that 1 meter (3.2 feet) of global sea level rise is possible by 2100.
The ice core also revealed significant surface melting of the Greenland ice sheet during the Eemian, just as there was in 2012, when it rained near the study site. This dynamic of intense surface melting will continue as the Arctic heats up faster than the rest of the globe, said Dahl-Jensen.
"The present warming over Greenland make surface melt more likely, and the predicted warming over Greenland in the next 50 to 100 years will very likely be so strong that we will potentially have Eemian-like climate conditions," she said.
Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500
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Add CommentKey point here, even though the Eemian warming happened "quickly" in geologic terms, it still took THOUSANDS of years to do what human CO2 emissions are doing in DECADES. On top of that, there wasn't a complex industrial society spread out over the globe during the Eemian either. Things are different now. We need to stop being lazy and DEAL WITH OUR MESS!
Reply | Report Abuse | Link to thisThe difference between the earlier period and now is the presence of significant amounts of black carbon in the atmosphere of the northern polar region. I assume it is much less in the Antarctic. Of course, over a thousand years black carbon might be controlled.
Reply | Report Abuse | Link to thisThe problem is that ignorant politicians are basing policy decisions on an immature science that has yet to have
Reply | Report Abuse | Link to thisANY of it's detailed predictions match experience.
The claim of omniscience by the Global Warming crowd is the reason for the backlash.
What appears to have happened is a warming that leveled off, in a typical hysteresis curve fashion. I have seen nothing to explain this.
Black carbon in the atmosphere exerts a cooling effect. That was established in the 1970s. It is the main reason to require precipitators on coal burning power plants. It seems to have worked.
Reply | Report Abuse | Link to thisTo now claim that this soot in the atmosphere is warming, goes against experience and solid science.
Soot on the surface DOES induce localized warming, however.
The 6/2010 article Melt Zone" in National Geographic talks about cryoconite --atmospheric dust which has historically been tan -- now being black. It says that altho only 5% of the cryoconite is soot, it is having a major effect on melting. Nat Geo has photos of moulins, vertical tunnels melted as lakes of meltwater plunge to the bottom of the Greenland ice cap. They talk of an 11 billion gallon lake taking 84 minutes to drain .. a flow greater than Niagara falls (average Niagara flow is about 2.5 billion gallons in 84 minutes).
Reply | Report Abuse | Link to thisGreenland, with between 836,000 and 860,000 square miles is a little larger than the Louisiana Purchase. So this 11 billion ice-melt lake is likely not unique.
A major assumption about the Greenland ice cap seems to be that it is this massive block of ice, subject to surface melt and run-off. This seems to be what we based our sea level rise predictions. The reality is that the ice cap is rotting away on the inside as all this liquid water flows --presumably to the base -- and acts as a lubricant to the glaciers flowing seaward.
this coupled with warmer seawater is causing ice shelves to break off at land's edge. Sea ice acts as a plug to slow glacial flow. Without those ice shelves, glaciers flow faster.
I also note that scientists seem to go with the more conservative predictions but.... i ran into an article a few months ago saying that a number of the predictions were off by as much as a factor of 10, and i think it likely it is true again. A foot of sea level rise in 90 years is way beyond conservative, especially when NASA photos showed 97% or so of the 800,000 square mile ice sheet turning to slush last summer. Another NASA related article said 150 gigatons of ice disappeared last summer.
True? i don't know but it's time to recalculate glacial melt and sea level rise using more realistic paramaters and data.
There are tons more glaciers down in Antarctica. Warmer ocean waters lapping at glaciers is not good. These glaciers touching the oceans are eroding from their underneath. We still don't know or can't see the bottoms of the glaciers and there are tons of them -
Reply | Report Abuse | Link to thishttp://www.cccarto.com/antarctica/