The ice cap at the North Pole melts in the summer and grows in winter; its general shrinking trend is a sign of global warming. The National Snow and Ice Data Center said today that Arctic ice was at 1.97 million square miles (5.1 million sq. Kilometers) when it stopped melting late last week.
It takes scientists several days to confirm sea ice hit reached its lowest level and is growing again.
The minimum level reached this summer is about 24 percent below the 20th Century average, but 50 percent above last year when a dramatic melt shattered records that go back to 1979. Center director Mark Serreze says cooler air triggered a "considerable recovery," from last year, while the ocean temperatures were still warmer than normal. But he adds climate change deniers who point to the bounce back from last year which skewed the trend would be wrong.
Overall, since 1979 Arctic sea ice has been shrinking at a "pretty darn big" rate of about 12 percent a year and "this is not going to reverse your trend, not in the least," Serreze says.