In case you don't have enough to worry about, consider that scientists are concerned about microbes and viruses long buried in the permafrost now being exposed to the light and air as the permafrost melts and releasing infectious agents like anthrax, smallpox and even bubonic plague.

Just last year in Siberia at least 20 people were infected with anthrax (Bacillus anthracis). The culprits, it's believed, are reindeer corpses locked in the frozen tundra now surfacing to infect soil and water. Scientist estimate over a million reindeer died in northern Russia alone in the last century.

The good news is not all bacteria can revive after being frozen. It is just spore-forming bacteria. Whew! That's a relief.