Hippopotamuses and Global Warming

Again, there has been rainforest evidence found at a coalmine. Last time fossil remains of plant life was found, and now there has been fossil evidence of tropical animals found in the Artic. These animals were plant eaters which resembled hippopotamuses and crocodiles.This evidence indicates that the Artic region had tropical, "Florida like", weather at one point in time.
Scientists say that this tropical climate in the Artic existed approximately 55 million years ago.

"According to Sluijs, forests grew in the Arctic when carbon dioxide, the main greenhouse gas, was at about 1000 parts per million in the atmosphere as a result of natural swings in the climate, perhaps linked to volcanic activity and a thaw of frozen methane.
Carbon dioxide levels are now at almost 390 per million in the atmosphere, up from 270 before the west's Industrial Revolution in the 19th century, and rising fast. It could reach 1000 parts per million by 2100 if not held in check, said Sluijs."

This is threatening because the Earth will not be able to support life in all of the regions where life exists today. The areas that are already warm will most likely be too hot to have life, and besides this, the water levels of these areas will probably be too elevated for survival. Global warming allows for the ice caps to melt, creating higher water levels which will result in a new environment for Earth.