Crabbe, I love the way the Greenhouse Effect will cause another glaciation, or, if it doesn't do that, the polar bears will starve - heads I win, tails you lose.
I don't think we can have a glaciation and runaway cooking simultaneously. I suppose the theory is that we'll get both, in sequence.
What will really happen is just as I've explained [assuming we are in time to prevent the next glaciation, which is no sure thing].
You say ice cover over the Arctic has decreased 50% in the last 50 years. You should see how much it decreased in the last 10,000 years. It used to be kilometres thick. A bit more and people will be able to drive ships through it, which will be very handy.
Polar bears are always hungry, unless they have just caught another dinner. There are too many of them anyway.
People are just bringing the carbon back to life, where it belongs. Plants have been on starvation rations for eons since the carbon got buried in vast deposits of limestone, coal, shale, bituminous goop, gas and oil graveyards. People are bringing it back to life.
CO2 is the bottom of the food chain and it had dwindled to a few parts per million. Plants would like to see it at parts per thousand, or more. 1 part per thousand would be a fair deal for plants and people. That should be an international goal. To be achieved by, say, 2050.
We need to think longer term for Earth's happiness, not the short term you mentioned:
<Never in the last 460,000 years have Green House gas concentrations even approached present day levels (Antarctic ice cores).> Too many people are thinking short term.
460,000 years? That's like yesterday. Add three zeroes. 460,000,000 is how long we should be thinking.
At that time, limestone, coal, oil and so on were not too common. Now, they are everywhere as living things spent eons stripping out the carbon and depositing it at the bottom of oceans and in swamps [now called wetlands which have become sacred]. Earth was dying and freezing as the atmosphere was stripped bare.
On a cold night, one needs nice thick blankets to stay warm. Go out to the edge of the atmosphere and take a look around. It's very very cold. We need a nice snuggly blanket to keep warm in a cold, hostile cosmos. The atmosphere is our blanket. The ice age got going because the blanket had worn thin and was not always enough to keep us warm.
Brrr....
Mqurice |
