Wednesday, December 17, 2014

Rising Air, Sea Temperatures are Impacting Fisheries

A global warming report released today by the National Oceanic and Atmospheric Administration says Arctic air temperatures are continuing to rise at twice the rate of global air temperatures, triggering dramatic changes in the Arctic.

“Arctic warming is setting off changes that affect people and the environment in this 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. McLean’s comment came during a news conference at the American Geophysical Union fall meeting in San Francisco.

“This year’s Arctic Report Card shows the importance of international collaboration on long-term observing programs that can provide vital information to inform decisions by citizens, policy makers and industry,” McLean said.

Contributors to the NOAA-led report included some 63 authors from 13 countries.

The annual update on effects of global warming has been provided since 2006. This year’s report includes major findings related to Arctic Ocean productivity, air temperatures, snow cover, sea ice, Arctic Ocean temperature, the Greenland ice sheet and vegetation, plus a new report on the status of polar bears.

The report notes that declining sea ice is leading to an increase in sunlight reaching the upper layers of the Arctic Ocean, setting off increased photosynthesis and greater production of phytoplankton, tiny marine plants which form the base of the food chain for fish and marine mammals. The timing of phytoplankton blooms throughout the Arctic Ocean is also being affected, with more frequent secondary blooms during the fall, the report said.

The report also notes that as sea ice retreats in summer, sea surface temperatures in all the seas of the Arctic Ocean is increasing. The most significant linear trend, the report said, is in the Chukchi Sea, northwest of Alaska, where sea surface temperatures are increasing at a rate of 0.9 degrees Fahrenheit every decade.

Air temperatures likewise have been changing. The jet stream pattern during early 2014 sent extreme cold air southward into eastern North America and central Russia and extreme warm air northward into Alaska and northern Europe. Alaska recorded temperature anomalies more than 18 degrees Fahrenheit, higher than the January average, the report said.


The complete report is online at http://www.arctic.noaa.gov/reportcard