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Annual report: Arctic continues to warm NOAA, partners say rate twice that of rise in global air temperatures; jet stream in early 2014 sent cold air south, warm air north Kristen Nelson Petroleum News
The National Oceanic and Atmospheric Administration-led report card on the Arctic released Dec. 17 shows Arctic air temperatures continuing to rise at more than twice the rate of global air temperatures. NOAA’s Arctic Report Card 2014, updating a report begun in 2006, shows “Arctic warming is setting off changes that affect people and the environment in the fragile region, and has broader effects beyond the Arctic on global security, trade and climate,” said Craig McLean, acting assistant administrator for the NOAA Office of Oceanic and Atmospheric Research, in a statement on the report’s release.
In comments prepared for an introduction of the report, principal editor Martin Jeffries, a program officer for Arctic and global prediction at the Office of Naval Research, said the report is the work of 63 scientists from 13 countries. The report is available online at: www.arctic.noaa.gov/reportcard/.
Continued impacts of warming “In 2014 we continued to see the impacts of a persistent warming trend that began over 30 years ago and which overlies significant year-to-year and regional variations,” said Jacqueline Richter-Menge of the Cold Regions Research and Engineering Laboratory. In early 2014, “the polar vortex weakened and the waves in the jet stream became more pronounced,” she said, moving cold air southward into eastern North America and central Russia, with warm air flowing north into Alaska and northern Europe.
“Alaska recorded temperature anomalies more than 10 degrees Celsius (18 degrees Fahrenheit) higher than the January average,” Richter-Menge said.
With the retreat of sea ice in the summer, surface temperatures are increasing, with the trend most apparent in the Chukchi Sea, “where sea surface temperature is increase at the rate of 0.5 degrees Celsius per decade.”
She also said that with larger regions of open water there are increases in production at the base of the food web.
Polar bears Geoff York of Polar Bears International said between 1987 and 2011 in Canada’s western Hudson Bay polar bear numbers decreased from approximately 1,200 to approximately 800, a decrease “linked to earlier sea ice break-up, later freeze-up, and thus, a shorter sea ice season.”
York said that in the southern Beaufort Sea where there are “now twice as many ice-free days over the continental shelf as there are immediately to the west in the Chukchi Sea,” the numbers of adult polar bears stabilized at approximately 900 by 2010 following a 40 percent decline since 2001.
“In contrast,” York said, “polar bear condition and reproductive rates in the Chukchi Sea may be stable at present - reflecting greater productivity of that system, fewer ice free days over the continental shelf, and a possible rebound from significant harvest in the mid-90s.”
Some mixed signals Jeffries said there are some mixed signals in the Arctic, with “evidence of a modest increase in the age of the ice and its thickness” in March 2014 relative to March 3013.
In summing up the current state of the Arctic environment, Jeffries said: “The impacts of the persistent warming trend of over 30 years remain clearly evident in the land and ocean environments, and these impacts are influencing the Arctic marine and terrestrial ecosystems,” with “continued widespread and sustained change throughout the Arctic environmental system” expected based on “consistent projections of continued warming temperatures.”
To see those changes, Jeffries said, it will be important to add to existing observing capabilities.
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