The Arctic is warmer than it's been in 2,000 years, even though it should be cooling because of changes in the Earth's orbit that cause the region to get less direct sunlight. Indeed, the Arctic had been cooling for nearly two millennia before reversing course in the last century and starting to warm as human activities added greenhouse gases to the atmosphere. The most recent 10-year interval, 1999-2008, was the warmest of the last 2,000 years in the Arctic, according to the researchers led by Darrell S. Kaufman from Northern Arizona University. The Arctic cooling had been the result of a 21,000-year cycle in the Earth's movement that caused the far north to get progressively less summertime energy from the sun for the last 8,000 years. That process won't reverse for another several thousand years.
