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Arctic shows no signs of returning to the reliably frozen state that it was in just a decade ago.

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The acting head of the National Oceanic and Atmospheric Administration, Timothy Gallaudet, released the 2017 Arctic Report Card. Unfortunately there is no good news in it, other than slightly less warming then last years record breaking warming.

( I updated this diary to add the following - There is a new chapter in geology beginning: Permafrost Lava! See video below.

There are more Greenland glaciers vulnerable then previously thought.

And scientists struggle to archive data from threats by the Trump Administration.

Note: These are not part of the Arctic Report Card)

EOS reports:

“Arctic temperatures continue to increase at double the rate of global averages,” he told reporters at a news briefing yesterday at the American Geophysical Union’s Fall Meeting in New Orleans, La. The mean Arctic air temperature this year over land exceeded the 1981–2010 average by 1.6°C, making it the second-highest average in the observational record after 2016, according to the NOAA report.

The report also found that the thickness of sea ice cover has continued to decline. Ice more than 1 year old composed just 21% of ice cover in 2017, whereas in 1985 it was 45%. Arctic ocean plankton blooms increased, as did overall land vegetation. Record permafrost warming has also occurred at many sites around the Arctic according to 2016 data, the most recent complete set of permafrost observations.

CBS News expands on the report

Sea ice in the Arctic Ocean is in a downward spiral, with summer minimum extents about 40 percent smaller than in the 1980s. But predicting how the sea ice is going to behave in a particular year is tricky: There are still many unknowns about the conditions of the sea ice cover, to say nothing of the difficulties of forecasting weather and ocean behavior over seasonal timescales.

New research looking into the Arctic's past using ice cores, fossils, corals and shells as stand-ins for temperature measurements show that Arctic ocean temperatures are rising and sea ice levels are falling at rates not seen in the 1,500 years. And those dramatic changes coincide with the large increase in carbon dioxide levels in the air from the burning of oil, gas and coal, the report said.

This isn't just a concern for the few people who live north of the Arctic Circle. Changes in the Arctic can alter fish supply. And more ice-free Arctic summers can lead to countries competing to exploit new areas for resources. Research also shows changes in Arctic sea ice and temperature can alter the jet stream, which is a major factor in U.S. weather.

This is probably partly responsible for the current unusual weather in the United States that brought destructive wildfires to California and a sharp cold snap to the South and East, according to NOAA scientist James Overland and private meteorologist expert Judah Cohen.

"The Arctic has traditionally been the refrigerator to the planet, but the door of the refrigerator has been left open," Mathis said.

Outside scientists praised the report card.

"Overall, the new data fit with the long-term trends, showing the clear evidence of warming causing major changes," in the Arctic, said Pennsylvania State University ice scientist Richard Alley.

Left: Greenland topography color coded color-coded from 4,900 feet (1,500 meters) below sea level (dark blue) to 4,900 feet above (brown). Right: Regions below sea level connected to the ocean; darker colors are deeper. The tin white line shows the current extent of the ice sheet. Credit: UCI. New maps of Greenland's coastal seafloor and bedrock beneath its massive ice sheet show that two to four times as many coastal glaciers are at risk of accelerated melting as previously thought.

Highlights The average surface air temperature for the year ending September 2017 is the 2nd warmest since 1900; however, cooler spring and summer temperatures contributed to a rebound in snow cover in the Eurasian Arctic, slower summer sea ice loss, and below-average melt extent for the Greenland ice sheet. The sea ice cover continues to be relatively young and thin with older, thicker ice comprising only 21% of the ice cover in 2017 compared to 45% in 1985. In August 2017, sea surface temperatures in the Barents and Chukchi seas were up to 4° C warmer than average, contributing to a delay in the autumn freeze-up in these regions. Pronounced increases in ocean primary productivity, at the base of the marine food web, were observed in the Barents and Eurasian Arctic seas from 2003 to 2017. Arctic tundra is experiencing increased greenness and record permafrost warming. Pervasive changes in the environment are influencing resource management protocols, including those established for fisheries and wildfires. The unprecedented rate and global reach of Arctic change disproportionally affect the people of northern communities, further pressing the need to prepare for and adapt to the new Arctic.

        

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