Arctic has its warmest year in history as experts say temperatures there are rising TWICE as fast as anywhere else in the world
- Air temperature over Arctic land reached 2.3 degrees F above average
- Also recorded lowest maximum extent since records began in 1979
The warming Arctic has set another record.
The average air temperature over Arctic land reached 2.3 degrees F (1.3 degrees C) above average for the year ending in September.
That's the highest sinceMaximum Arctic Ocean sea ice extent, which occurred February 25, 2015, 15 days earlier than average, was the lowest extent recorded since records began in 1979
observations began in 1900.
The average air temperature over Arctic land reached 2.3 degrees F (1.3 degrees C) above average for the year ending in September.
The new mark was noted in the annual Arctic Report Card, released Tuesday by the National Oceanic and Atmospheric Administration.
The Arctic centers on the North Pole and reaches into North America and Eurasia.
'Warming is happening more than twice as fast in the Arctic than anywhere else in the world,' NOAA chief scientist Rick Spinrad told reporters in San Francisco at a meeting of the American Geophysical Union.
'We know this is due to climate change,'
He also said the changes would have huge effects on the planet.
'The Arctic is warming twice as fast as other parts of the planet, which has ramifications for global security, climate, commerce, and trade. T
'This year's report shows the importance of international collaboration on sustained, long-term observing programs that provide insights to inform decisions by citizens, policymakers, and industry.'
Another record emerged for sea ice, which appears when Arctic Ocean water freezes.
WHAT THEY FOUND: THE RECORD BREAKING YEAR IN THE ARCTIC
Air temperature: The average annual air temperature over land areas between October 2014 and September 2015 was 2.3 degrees Fahrenheit (1.3 degrees Celsius) above average, the highest in the observational record which began in 1900, and is a 5.4 degrees Fahrenheit (3 degrees Celsius) increase since the beginning of the 20th Century.
Sea ice: Maximum Arctic Ocean sea ice extent, which occurred February 25, 2015, 15 days earlier than average, was the lowest extent recorded since records began in 1979. Minimum sea ice extent measured on September 11, 2015, was the fourth lowest in the satellite record since 1979. Arctic minimum sea ice extent has been declining at a rate of 13.4 percent per decade (relative to the 1981-2010 average). First year ice now dominates the winter ice cover, comprising about 70 percent of the March 2015 ice pack, compared to about half that in the 1980s when older, thicker ice was more prevalent. The thinner, younger ice is more vulnerable to melting in the summer.
Maximum Arctic Ocean sea ice extent, which occurred February 25, 2015, 15 days earlier than average, was the lowest extent recorded since records began in 1979
Snow cover: While Arctic-wide terrestrial snow cover extent in April was above average, June snow cover in both the North American and Eurasian parts of the Arctic was the second lowest in the satellite record that began in 1967. Arctic-wide June snow extent has declined 18 percent per decade since 1979. Snow cover variability in April through June is important as the Arctic's transition from winter to summer affects climate and terrestrial ecosystems.
Greenland ice sheet: For the first time since the exceptional melt of 2012, significant melting (more than 50 percent of the area) occurred on the surface of the Greenland ice sheet in 2015. Melt season was 30 to 40 days longer than average in western, northwestern and northeastern Greenland, but was close to or below average elsewhere on the ice sheet. Between the end of the 2014 and 2015 melt seasons, 22 of 45 of the widest and fastest flowing glaciers terminating in the ocean had retreated, but the advance of 9 relatively wide glaciers resulted in a low annual net loss of 6.4 square miles (16.5 square kilometers).
For the first time since the exceptional melt of 2012, significant melting (more than 50 percent of the area) occurred on the surface of the Greenland ice sheet in 2015.
Arctic Ocean temperature: As sea ice retreats in summer, sea surface temperature (SST) in all the seas of the Arctic Ocean is increasing. Mean sea surface temperatures in ice-free regions in August 2015 ranged from 32 degrees Fahrenheit (0 degrees Celsius) to 44 to 46 degrees Fahrenheit (7 to 8 degrees Celsius) in the Chukchi, Barents and Kara seas and eastern Baffin Bay off the west coast of Greenland. The Chukchi Sea northwest of Alaska and eastern Baffin Bay off west Greenland have the largest warming trends: nearly 1 degree Fahrenheit per decade since 1982 (0.5 degrees Celsius).
Vegetation: For reasons that remain to be identified, tundra greenness has been declining, or browning, consistently for the past two to four years.
tundra greenness has been declining, or browning, consistently for the past two to four years.
When it reached its peak coverage in February, it was the lowest maximum extent since records began in 1979.
The minimum ice coverage, reached in September, was the fourth lowest on record.
The retreat of sea ice is considered a threat to animals like walruses, which use it for mating, giving birth and getting out of the water.
Walruses can use land instead to leave the water, but they are crowding onto beaches where a stampede can be devastating for calves, two editors of the report card told AP.
Ice floes in Baffin Bay above the Arctic Circle, seen from the Canadian Coast Guard icebreaker Louis S. St-Laurent. In the annual Arctic Report Card, released Tuesday, Dec. 15, 2015 by the National Oceanic and Atmospheric Administration, a record emerged for sea ice, which appears when Arctic Ocean water freezes.
Walruses have been hauling themselves out on land in northwest Alaska, a recent phenomenon, Martin Jeffries of the federal Office of Naval Research and Jackie Richter-Menge of the U.S. Army Corps of Engineers wrote in a joint email.
Snow cover in June in both the North American and Eurasian parts of the Arctic was at the second lowest level since records began in 1967.
Reduced snow cover lets more sunlight through to the land, which absorbs the energy and gets warmer.
Since 1979, the extent of June snow cover has been dropping by 18 percent per decade, the study said.
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