Polar sea ice declines to lowest seasonal levels in four decades

Arctic sea ice at the Earth’s north polar region declined to record low winter levels in March according to data released Wednesday by the National Snow and Ice Data Center in Boulder, Colo.

NSIDC’s report, sponsored by the University of Colorado and an affiliate of NOAA, said Arctic ice likely reached maximum capacity on March 7 when there was approximately 5.57 million square miles of coverage.  Satellite imagery shows this is the lowest amount of sea ice observed in the Arctic during winter season since data started being recorded in the late 1970s.

The previous winter Arctic low was set in 2015, when there was about 35,000 more square miles of sea ice than currently exists. While NSIDC only reports total ice coverage in terms of width, European Space Agency satellite data also shows ice depth is at its lowest seasonal level in four years.

In addition, the University of Washington’s Polar Science Center recently reported that total ice volume in the Arctic as of late February has declined by a total of 42 percent since 1979.

NSIDC also reported sea ice in the Antarctic south pole region has reached its all-time, 38-year low as of March 3, with 286,000 square miles less coverage than the average annual summer season low calculated between 1981–2010.

According to climate scientists, a weakened jet stream is the main, direct cause for increased melting of Arctic ice, as three “extreme heat waves,” have encompassed the north pole during 2016–’17’s winter season.  A less protective jet stream has caused more variable patterns in the polar vortex — an atmospheric low pressure, cold air system — bringing extreme winter weather to points south of the North Pole, namely North America, Europe and Asia.

Increased carbon dioxide particles in Earth’s atmosphere has also caused the planet’s temperatures to increase overall, contributing to at least half of what ice has already melted, multiple studies have found.

“The annual freeze and thaw of sea ice in the polar regions is like the beating heart of our planet, driving ocean circulation and regulating our climate,” said World Wide Fund for Nature polar policy director Rod Downie. “But sea ice is in decline in a warming world and the record have been shattered this year.”

Other climate science research has shown that melting polar ice itself can increase average global temperatures because darker colors of the ocean become more exposed, trapping and absorbing heat from the sun’s rays, instead of deflecting it as white shades of ice and snow do.

Melting polar ice also endangers the natural habitats of polar bears and penguins, and increases shipping boat traffic due to clearer sea lanes, the latter which may also be a contributing factor in long-term global warming trends.

 

[AP] [Climate Central via Scientific American] [The Guardian]