Why is there so much stored carbon in permafrost areas?
Because there was a full and abundant plant life in these areas prior to the start of the ice age that we are still technically in, that seems to has started, around 2.5 million years ago. The planet would not have gone from a warm, plant-filled with adequate carbon dioxide in the atmosphere to a cold icebound planet in a short period. It would have been much more likely a small start and stop process, which would have cooled the northern and southern areas the quickest, locking in of whatever carbon was in the soils at the time, because the bacteria that had been most responsible for the break-down of the carbon in the now cool soils, would not have been as efficient as today's bacteria, which is now used to being active at lower temperatures as compared to when the soils were generally warmer, one would think that that adaptation would have not come into play until needed! The longer that an area has been frozen and then lightly thaws over and over cause the soils in the permafro...