Are Arctic temperature shifts tied to global warming?
By Bob Berwyn
SUMMIT COUNTY — Colder-than-average temperatures may be prevailing across the U.S., Europe and parts of Asia so far this winter, but the Arctic region has been much warmer than average, according to the latest bulletin from the National Snow and Ice Data Center.
In some parts of the Arctic, air temperatures were about 13 degrees Fahrenheit above average, leading to a reduced extent of sea ice in the area. The temperature anomalies are due in part to a pattern called the Arctic Oscillation, a cyclical pattern tied to barometric air pressure in the region.
This past December’s variation from “average” was the farthest since at least 1950 and may be tied to global warming. Temperatures in the Arctic region have implications for climate across the rest of the planet.
The Arctic sea ice extent averaged during December 2009 was about 350,000 square miles less than the average for period spanning 1979 to 2009, according to the NSIDC, but still 81,000 square miles more than the record low for December in 2006.
Global warming skeptics have used the recent cold temperatures to try and bolster their arguments that human emission of greenhouse gases are not changing the global climate, but scientists say it’s important to look at the climate picture globally and over time, rather than isolating short-term weather patterns.
Some research suggests that atmospheric pressure patterns are changing in mid-latitudes and in the Arctic, and that the changes are related to the rapid buildup of greenhouse gases in the atmosphere and to the associated decline in Arctic sea ice.
The World Wildlife Fund maintains an excellent web site and blog about climate change in the Arctic, with links to some of the relevant research.