BOULDER, Colo., Sept. 16 (UPI) -- Only a month ago, scientists were suggesting the rate of sea ice melting in the Arctic had slowed and the 2016 minimum was unlikely to break any records.
Fast-forward to early September, as Arctic sea ice levels reached their summertime minimum, and 2016 has joined 2007 for the second lowest minimum on record.
"It was a stormy, cloudy, and fairly cool summer," Mark Serreze, director of the National Snow and Ice Data Center, said in a news release. "Historically, such weather conditions slow down the summer ice loss, but we still got down to essentially a tie for second lowest in the satellite record."
At its low point on September 10, the NSIDC reports Arctic sea ice covered just 1.6 million square miles. The all-time record belongs to 2012, with a minimum coverage of just 1.3 million square miles.
Between 1981 and 2010, Arctic sea ice lost an average of 8,100 square miles per day during its melting months. In 2016, Arctic sea ice lost an average of 13,200 square miles per day.
Melting rates slowed in midsummer as cool, cloudy weather stalled over the North Pole, but that period of respite was bookended by record high temperatures and accelerated melting. Even so, scientists were surprised by this year's minimum.
Researchers suggest a plethora of especially thin ice at the end of the winter -- a winter that also set a record low -- contributed to the record melt. Water temperatures were above average in the upper ocean during the late summer months, contributing to accelerated ice loss to end the melt season.
Researchers say they'll now begin to explore the causes for this year's melt.