Shrinking … the Arctic ice.SEA ice in the Arctic was melting at a record pace last month, according to the US National Snow and Ice Data Centre.
Measurements taken on June 18 showed the area containing sea ice had shrunk to 10.62 million square kilometres, about 31,000 square kilometres lower than the previous record for that day, set in in 2010.
The rate of melt slowed slightly later in the month, so it is not yet clear whether this year’s melt will challenge 2007, the year in which sea ice reached its lowest extent since instrumental records began.
”Early melt onset, and clear skies near the solstice are favourable conditions for more rapid melting, and warming of the ocean in open water areas,” the US National Snow and Ice Data Centre said in its report.
”The persistence of this type of pressure pattern throughout summer 2007 was a major factor towards causing the record low September extent that year,” continued the report.
An update issued at the weekend showed the ice extent tracking below the 2007 figure, but the agency cautioned that it was much too early to say if this year would break the record for melting ice.
”While the extent is at a record low for the date, it is still early in the melt season,” it said. ”Changing weather patterns throughout the summer will affect the exact trajectory of the sea ice extent through the rest of the melt season.”
The driving force behind the current fast melt was regional weather conditions, the agency said, including warm winds sweeping north from east Asia.
Separate observations at the University of Washington supported the agency’s assessment that ice had been melting at a faster rate this year.
The Arctic is a key site for climate science, because the impact of warmer air and water temperatures can be directly measured. The speed and scale of the annual melt is scrutinised by scientists each year for signs of change.
The trend towards a shrinking polar ice cap has been evident, and has been growing more pronounced, for at least four decades as global temperatures have risen.
The loss of Arctic ice presents a massive problem for attempts to contain dangerous climate change at safer levels, because the white ice reflects light and heat away from the Earth’s surface. The smaller the ice cap, the less heat is reflected away, and the warmer the water, leading to further loss of ice.
This story Administrator ready to work first appeared on Nanjing Night Net.