From reindeer to regional temperature patterns, from sea ice age to Greenland surface melt, the Arctic Report Card is a yearly assessment of the Arctic's physical and biological systems and how they are changing. This collection of visual highlights from the 2013 report is a story of the Arctic in pictures.
Since the mid-1960s, the Arctic has warmed about 3.6°F (2.0°C)—more than double the amount of warming in lower latitudes. In 2012 (the last complete calendar year available at the time scientists began working on the 2013 Arctic Report Card), the annual average temperature was the sixth warmest on record.
After record-breaking melt during the 2012 season, the 2013 melt extent was more on par with the long-term average. The reprieve from the record warmth and melting of the past six summers is likely connected to a strong positive phase of the North Atlantic Oscillation during summer 2013.
Most of the Arctic boundary waters were warmer than average in summer 2013, but a few cool pockets appeared in the western Arctic and the Greenland Sea. Warmer waters are drawing new species from lower latitudes into the Arctic.
In May 2013, there was record-setting loss of Eurasian spring snow cover, and spring snow cover was below normal again in June—the fourth lowest on record. This is the sixth year in a row that Eurasia has set a new record low in either May or June snow extent.
Averaged over September 2013, sea ice extent was 2.07 million square miles—larger than last year's record low, but still more than 17 percent below average and the sixth smallest September extent on record.
Models project that extreme dust events combined with global warming could advance the spring thaw in the mountains of the Upper Colorado River Basin by as many as 6 weeks by 2050. The earlier disappearance of snow could amplify water disputes, extend the fire season, and stress aquatic ecosystems.
To be consistent with NOAA's use of 30-year periods for the official "climate normals," the National Snow and Ice Data Center switched its baseline period for sea ice analyses from 1979-2000 to 1981-2010. Compared to the new normal, the low ice conditions of the recent past will appear less abnormal than they used to.
On July 30, 2013, a weather station on the southwest coast of Greenland preliminarily set a new record high temperature for the country, but whether it will stand as an "official" record after scientists apply quality control procedures isn't yet known. What is known? Greenland's getting warmer.