dohboi wrote:vt, sorry I didn't specify summer-time ice-free Arctic. Keep in mind that the most pessimistic models that the IPCC put out just two years ago showed an intact ice cap for at least decades. The most pessimistic models seem to regularly not be pessimistic enough, mostly because of the difficult of modeling interactions of multiple feedbacks.
But even an Arctic ocean free of ice for a few weeks or months is going to change the climate patterns in the No Hemisphere, probably in profound and unpredictable ways.
Keep in mind also that the highest use of electricity is in the late summer, just when any such calming effect is likely to kick in.
One more thing to keep in mind: in the act of melting, the ice cap significantly cools the water around it. Once the ice cap is gone, not only will it not reflect light, it's melting will no longer act too cool the surrounding water. This is likely to lead to (relative) super heating. We already saw areas last summer where water temps were 7+ degrees C (as I recall) above long-term averages.
You tend to be quite cagey in your answers, so let me ask straight out: Do you view the impending total melt of the ice cap, an event that hasn't happened since long before human civilization first started to develop, as on even of little consequence?
Considering that the poles spend some 163 days in the dark each year and that the elevation of the Greenland ice cap and the interior of Antarctica are as high as they are I don't see the total melt of the ice caps as more then a remote possibility.
From the CIA data site. Antarctica
Terrain: about 98% thick continental ice sheet and 2% barren rock, with average elevations between 2,000 and 4,000 meters; mountain ranges up to nearly 5,000 meters; ice-free coastal areas include parts of southern Victoria Land, Wilkes Land, the Antarctic Peninsula area, and parts of Ross Island on McMurdo Sound; glaciers form ice shelves along about half of the coastline, and floating ice shelves constitute 11% of the area of the continent
Elevation extremes: lowest point: Bentley Subglacial Trench -2,555 m
highest point: Vinson Massif 4,897 m
note: the lowest known land point in Antarctica is hidden in the Bentley Subglacial Trench; at its surface is the deepest ice yet discovered and the world's lowest elevation not under seawater
But that said even the melting around the edges and the reduction in summer ice cover on the arctic ocean that is being predicted and observed is more then enough to have adverse impacts on the environment and the human population.
But I think the more immediate problem is the worlds population and its uncontrolled growth. I expect that to come to a head and be resolved in a very unpleasant way which will make peak oil and global warming moot points sometime in the next twenty years or so.