Quote:
Originally posted by JR@Jun 23 2003, 09:40 AM
it was not too long ago that we were worried about global cooling.
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True. I have an old weather book (c. 1977) and a 1970's essay by Isaac Asimov that both talk about how pollutants will block the sun's rays and hence cool the planet.
That there are natural fluctuations is quite evident. The ice age of just 10,000 years ago are evidence enough of that.
Surely CO2 emissions are warming the planet. I don't think anyone knows to what degree or whether it is a real problem or not.
Seems to me that computer simulations will be the best way forward. Most computer simulations that try to model such things have made very poor predictions so far - often overpredicting the temperature rise. I think until we at least get that far we're in the "Don't know" category. Trying to model a system as complex as the Earth's long-term climate is no short order. There are incredible resources being devoted to the Earth's climatology and it is a quite popular subject.