Maybe you've heard about the permafrost that is proving not so permanent in the world's colder places.
Melting permafrost is damaging and even swallowing houses and bigger buildings.
And a recently published study shows greenhouse gas buildup figures prominently in the warming of Russia, contrary to prevailing theory.
Matthew Lachniet at the University of Nevada-Las Vegas is one of the authors. He visits with details of what he and partners found deep in a cave in the Urals.