Climate Central: An intense heat wave in Siberia has contributed to an unusual flare up of wildfires across the fragile and carbon-rich landscape. Smoke from the fires is lofting high into the atmosphere, and is drifting toward the Arctic, where soot can hasten the melting of snow and sea ice. The Siberian city of Norilsk, the most northerly city in the world with a population greater than 100,000, recorded temperatures above 83°F over eight consecutive days starting on July 18, according to blogger Chris Burt of...