Saw a program last night that mentioned how the earth got all its coal deposits: Eons of tropical climate and its accumulated biomass under pressure. Must have been quite the wet bog back then for it not to have broken down into live aerated soil.
How cyclical things are on this planet. They say there were several times when the earth was a giant ice covered snowball, interrupted by long tropical periods.
Now so much of that captured carbon has been re-released into the atmosphere. And the re-released methane. Whether one blames this recent warming trend on the sun or on human activity, perhaps it is both, the earth will return to its prehistoric boggy condition to build up its coal deposits once again.
What we definitely are doing is depleting the resources upon which our population explosion relies. Like ever-multiplying yeast colonies, when we reach the edge of our Petri dish, what then?