The Antarctic Ice Sheet Is Growing?

That IS enough to make some people disbelieve the climate scientists because, after all, no one wants to think the climate is going to steadily get worse. We all secretly hope that the deniers are right.

Yes, the Antarctic ice sheet is growing in height in the central region, but making just that one point is very misleading and quite dishonest.

There is an enormous amount of research that has been conducted on the poles and there is much more to the story than just the increase in snow in the middle of the continent. Indeed the coast is where the real action is.

The leading U.S. climate scientist Dr. James Hansen responded via email saying "The most precise data on the mass of the ice sheets, from the gravity satellite, show that, overall, Antarctica is losing mass, as is Greenland, even though East Antarctica is gaining a small amount of mass."

"All of the models, and the observations, have the central parts of Greenland and Antarctica growing faster because of global warming. This is a consequence of warmer air holding more moisture, thus increasing snowfall. But the net effect of warming on both continental ice sheets is mass loss, the increased melting being a larger effect than the increased snowfall.

He also said "The fact that West Antarctica is shedding mass at a substantial rate, even though there is only small warming of surrounding sea surface temperatures, is a telling fact in my opinion, and a likely consequence of the warming ocean at depth, which affects the ice shelves that buttress West Antarctica, as discussed in our paper "Dangerous human-made interference with climate: a GISS modelE study."" [1]

Apples and Oranges

But the reason that the North Pole is melting so much faster (last years summer minimum shattering the previous record of 2005) than the South Pole is very easy to understand.

The South Polar Ice Sheet is two miles thick. That means that the ice is at an altitude of over ten thousand feet where the temperature is much colder than a mere six or so feet as at the North Pole. This makes it impossible for the slight rise in global mean temperature to have any affect at all in the south accept around the edges of the continent.

Also, it sits on a continent rather than on water that is above freezing - as in the north. The ice in the north is an average of 6 to 12 feet thick and is being warmed from beneath as well as above. This has a much larger impact on the North Polar Ice Cap.

Dr. Hansen also pointed out that the ozone hole (the portion of the lowest ozone being roughly the size of the Antarctic ice sheet) is letting more heat escape into the atmosphere as the ozone is a greenhouse gas. [2]

The South Pole is quite literally the coldest place on Earth, and it always will be much colder than the North Pole no matter how much global warming occurs. The Greenland Ice Sheet is very similar to the South Pole and the research shows that it, too, is melting at an accelerated pace around the edges.

"....between 1996 and 2005, they detected a widespread glacier acceleration and consequently an increased rate of ice discharge from the Greenland ice sheet," write three climate scientists in an article for RealClimate.org of research published after the Intergovernmental Panel on Climate Change (IPCC) report was written. [3]

It would seem that the north and south poles should react the same, but because of these gigantic differences they cannot. Antarctica is not the canary in the mine..........the canary is the Arctic, and it's telling the scientists that things are changing faster than they had thought possible.

Don Beck

***********

1] Dangerous human-made interference with climate: a GISS modelE study
http://www.atmos-chem-phys.net/7/2287/2007/acp-7-2287-2007.pdf

2] 2007 Ozone Hole 'Smaller Than Usual', 10/4/07
http://www.sciencedaily.com/releases/2007/10/071003100537.htm

3] The Greenland Ice,3/2/06
http://www.realclimate.org/index.php?p=267

Here is a another article about the power of the oceans on the climate.
Think Not 'Global' Warming - Think 'Oceans' Warming
http://sydney.indymedia.org.au/story/think-not-global-warming-think-oceans-warming