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We are putting out a lot of carbon dioxide into the atmosphere. Some people worry about methane, but the effect is likely negligible because methane doesn't last very long in the atmosphere.They are right to worry. The effect of CH4 is about .5 Watts per square meter as compared to pre-industrial times. Crudely speaking, this accounts for about a quarter of a degree of warming.
accelerate global warming with our increased output of carbon dioxide, but we did it at a time when global temperatures had already been increasing for thousands of years.Time scales matter.
We need to better define what the crisis is.Eemian warmth was different. At this time the orbital eccentricity was more than double the current value. With perihelion occurring in summer, this led to strong increases in summer temperatures, decreases in winter. The obliquity was also larger, meaning more heat in higher latitudes.
We probably should be nearing the end of the current warming period. For the last million years we have had the 100,000 year ice age cycles. The earth has been cooling for the last 3 million years, but for the last million we went to a cycle of around a hundred thousand years of cold interspersed with 20 to 30 thousand years of warmer climate. The temperatures of the cycles seem to have become more extreme in the last 500,000 years. The last warm period got warmer than it is now, and more ice melted and sea levels were 20 meters higher than they are now.
have not reached that point, yet in this cycle, so things are not yet as bad as they got without human industrial interference.As one of the authors of such a paper, I have to disagree with your interpretation.
There was an article put up on TO, maybe a decade ago, that claimed that the current carbon dioxide levels could prevent a recession into another ice age.
be that bad.Nor would it be good. Ice ages begin very slowly in human terms. If we still are an industrial society when the next one comes along - some time in the next twenty thousand years - we will be able to deal with it.
temperatures fell for the mini ice age that started in the 1300's and didn't end until the start of the industrial revolution that is supposed to be responsible for our current global warming.The little ice age ended well before CO2 from industry became a significant factor in climate. It has been shown that stratospheric aerosols caused by increased volcanism account for about 60% of the little ice age cooling. Given the noisy data, that's about as good as can expect, though solar, GHG and land-use effects were also accounted for.
warmer climates that had more ice melting and sea levels rising to the levels that they claim may occur this time, but they obviously happened before. So the regions that will be flooded will just be a repeat of what happened last time a hundred thousand years ago.You are drawing parallels where there are no parallels. See above.
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