Ruth Weiner wrote
"Moreover, the global consequences of global warming may not be all bad and are certainly
going to come about very slowly."
It depends on what you mean by very slowly. I think that we will agree that very slowly in human perception is very different from very slowly in the geological time frame. However, the grand old man of oceanography/CO2, Wallace Broecker at the Lamont-Doherty Earth Observatory at Columbia University recently found evidence in deep-sea cores from the Atlantic that ocean currents could change quickly, on the order of 100 years if I remember correctly, which, while it is greater than the normal human life span is probably quicker than the time it takes for human society to adapt in a smooth fashion. The response of the weather patterns to shifts in currents such as the Gulf Stream certainly could bring on another ice age. There are many unknowns in the equation, not the least of which is the potential that the shift in ocean currents could release methane hydrates which are now buried beneath sediments near the Blake Plateau off the SE coast of the US and in other areas of the world. Another variable is the release of frozen methane in the artic due to increase warming of the earth's surface. With 16x the global warming capacity of CO2, methane sources are a wild card in the temperature projection calculations.
Given human nature, it is unlikely that society will react unless faced with a crisis. It's like the story about the frog and boiling water. Drop a frog into cold water and start a fire and it will swim around happily until he is boiled. But drop a frog into very hot water and it will try to jump out in response to the sudden change. Taking the human race into a climate regieme in which it has never before lived is a prospect I find unsettling. It may be comfortable for a while, but will we, as a society and individual people, successfully adapt?
Just my own thoughts and not necessarily those of my employer
Kjell Johansen
Wisconsin Electric
Milwaukee, WI
kjell.johansen@wepco.com