Huge part of Antarctica thawed in ’05

Vast areas of Antarctica melted in 2005 when temperatures rose for a week, in a process that may accelerate invisible melting deep beneath the surface, NASA said this week.

An analysis of satellite data showed that an area the size of California melted and then refroze -- the most significant thawing in 30 years. Son Nghiem of NASA’s Jet Propulsion Laboratory in La Canada Flintridge and Konrad Steffen of the University of Colorado at Boulder found evidence of melting in several areas, including high elevations and far inland, in January 2005, when temperatures got as high as 41 degrees. Snowmelt could penetrate to the bottom of ice sheets, “causing the ice mass to move toward the ocean faster, increasing sea level,” Steffen said on NASA’s website.