Long-term climate records from the Arctic provide strong new evidence that human-caused global warming can override Earth’s natural heating and cooling cycles, U.S. researchers reported this week in the journal Science. For more than 2,000 years, a natural wobble in Earth’s axis has caused the Arctic region to move farther away from the sun during the region’s summer, reducing the amount of solar radiation it receives. The Arctic is now 600,000 miles farther from the sun than it was in AD 1, and temperatures there should have fallen a little more than 1 degree Fahrenheit since then. Instead, the region has warmed 2.2 degrees since 1900 alone, and the decade from 1998 to 2008 was the warmest in two millenniums, according to a team headed by climatologist Darrell S. Kaufman of Northern Arizona University. Not only was the last half-century the warmest of the last 2,000 years, ‘but it reversed the long-term, millennial-scale trend toward cooler temperatures,’ Kaufman said. The results seem to negate the primary argument of those who say the current warming of Earth is simply a natural variation, he said. The Arctic region has actually warmed about three times as much as […]