A new report shows that unprecedented warming air temperature in 2016 over the Arctic contributed to a record-breaking delay in the fall sea ice freeze-up, leading to extensive melting of Greenland ice sheet and land-based snow cover.

Permafrost is thawing across the Arctic, according to the report, sponsored by the National Oceanic and Atmospheric Administration, causing northern lands to sink or change shape. In Gates of the Arctic National Park, a lank bank lake thawed, allowing the Okokmilaga River to cut through and drain it to sea. Scientists are particularly concerned about what will happen as the frozen ground releases carbon dioxide and methane that were formerly stored under the surface.

Arctic melting has implications for transportation and trade. Once those reaches are relatively ice free, shipping could take northern routes to cut transportation times, fuel consumption, and costs on routes from Asia to Europe and the Americas.

“Rarely have we seen the Arctic show a clearer, stronger or more pronounced signal of persistent warming and its cascading effects on the environment than this year,” said Jeremy Mathis, director of NOAA’s Arctic Research Program. “While the science is becoming clearer, we need to improve and extend sustained observations of the Arctic that can inform sound decisions on environmental health and food security as well as emerging opportunities for commerce.”

The Greenland ice sheet continued to lose mass in 2016, as it has since 2002 when satellite-based measurement began. Melting began the second earliest in the 37-year record of observations, close to the record set in 2012.

The Greenland ice sheet continued to lose mass in 2016, as it has since 2002 when satellite-based measurement began. Melting began the second earliest in the 37-year record of observations, close to the record set in 2012.

The report concluded that average annual air temperature over land areas was the highest in record, representing a 6.3 degree Fahrenheit (3.5 degree Celsius) increase since 1900. Arctic temperatures continue to increase at double the rate of the global temperature increase.

Spring snow cover set a record low in the North American Arctic, where the May snow cover extent fell below 1.5 million square miles for the first time since satellite observations began in 1967.

The report also observed record low sea ice. The Arctic sea ice minimum extent from mid-October 2016 to late November 2016 was the lowest since the satellite record began in 1979 and 28 percent less than the average for 1981-2010 in October. Arctic ice is thinning, with multi-year ice now comprising 22 percent of the ice cover as compared to 78 percent for the more fragile first-year ice. By comparison, multi-year ice made up 45 percent of ice cover in 1985.

Sea surface temperature in August 2016 was nine degrees Fahrenheit (five degrees Celsius) above the average for 1982-2010 in the Barents and Chukchi seas and off the east and west coasts of Greenland.

Springtime melting and retreating sea ice allowed for more sunlight to reach the upper layers of the ocean, stimulating widespread blooms of algae and other tiny marine plants which form the base of the marine food chain, another sign of the rapid changes occurring in a warming Arctic.