Ahem. Citations, please. There is no land at the north pole, so therefore there would be no palm trees and definitely no mammoths.
There is some discussion as to what these animals were eating (tropical plants, or regular plants), and how quickly they froze (very suddenly, or more slowly). Here are a couple of paragraphs from http://www.icr.org/pubs/imp/imp-128.htm :
The bones of thousands of animals have, in fact, been found frozen in the tundra of Siberia. Hippopotamuses, sabertooth tigers, mammoths, and other animals normally associated with the tropics have been found frozen, some in relatively fresh condition in the frozen Siberian muck. This muck is full of plant and animal remains to depths of several thousand feet.I'm not an expert on this topic, but do find it fascinating. I'm not "settled" in what I believe about these animals, and will continue to read up on them.The presence of fresh tropical plants and flowers in the stomachs of certain frozen Siberian mammoths indicates the temperature drop in some locations occurred suddenly. The fact that some of the mammoths were frozen in the muck and were found relatively fresh, indicates that the temperature drop was extreme and permanent. Such a scenario matches the predictions of the vapor canopy model very well.