In 2012, multiple observations provided strong evidence that the Arctic environmental system is entering a new state. Major changes in recent years are widespread, sustained and occurring faster than anticipated. The minimum Arctic sea ice extent in 2012 was nearly half the values seen at the end of the last century. Early snow melt in northern Asia and North America for June has set records repeatedly in the past 5 years, declining three times faster than predicted. The rapid loss of Greenland ice sheet mass is continuing. In 2012, surface melting was the most widespread in the satellite record, and satellites captured a rare melt event impacting 97% of the surface area. Greenland is a climate "wild card" because of its potential for causing dramatic increases in sea level. Also occurring in 2012, permafrost temperatures in Alaska are at record highs. Tundra continues to become greener, with the growing season longer in Eurasia. For the first time, a massive phytoplankton bloom was observed, under 3-foot thick Arctic sea ice, and there were varied impacts on marine and terrestrial wildlife. Taken together, the large environmental shifts in 2012 provide evidence of sustained Arctic change.