Monday 25 February 2013

Arctic Melting Volume of Arctic Sea Ice 1979-2012. Sea ice volume in 2012, was 1/5th of what it was in 1980.

Arctic Melting



sea ice volume 2012

Volume of Arctic Sea Ice 1979-2012. Sea ice volume in 2012, was 1/5th of what it was in 1980. psc.apl.washington.edu



arctic sea ice volume


Spiralling toward an ice free winter. The black line is September volume from 1979 to 2012... haveland.com



arctic sea ice volume

Sea Ice Volume is calculated using the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS). psc.apl.washington.edu




haveland.com

The volume of sea ice is actually a much more accurate indicator of loss of ice, than sea ice extent. The findings are the result of a huge international collaboration - CryoSat-2 - between teams from UCL, the European Space Agency, the Jet Propulsion Laboratory, the University of Washington, York University, Alfred Wegener Institute for Polar & Marine Research, Woods Hole Oceanographic Institution, Morgan State University and the University of Maryland. www.washington.edu



arctic ice 2012
Arctic Sea Ice Extent Sept 17, 2012. ocean.dmi.dk
Arctic sea ice in 2012 hit a record low. Sea ice covered less than 24% of the Arctic Ocean in September. The National Snow and Ice Data Center reports that Arctic sea-ice extent fell to 1.32 million square miles, well below the previous record low, set on Sept. 18, 2007 of 2.07 million square miles. Professor Peter Wadhams of Cambridge University has just predicted the disappearence of Arctic sea ice could occur, during the months of August and September, as soon as 2016.






The sea ice in the Arctic Ocean dropped below the previous all-time record set in 2007. 2012 also marks the first time that there has been less than 4 million square kilometers (1.54 million square miles) of sea ice since satellite observations began in 1979. This animation shows the 2012 time-series of ice extent using sea ice concentration data from the DMSP SSMI/S satellite sensor. The black area represents the daily average (median) sea ice extent over the 1979-2000 time period. Layered over top of that are the daily satellite measurements from January 1 -- September 14, 2012. A rapid melt begins in July, whereby the 2012 ice extents fall far below the historical average.



A contributor to this years record loss was an unusual Arctic storm with 50 mph gusts which came up from Siberia on August 6th and churned in the Arctic for a few days. The storm had a low pressure of 963 mb on the 6th and continued with 970 on the 8th. It is very unusual for such a low pressure storm to be in the Arctic in the summer. From August 6th to 8th, the storm broke up the ice very rapidly and a continued decline has set unprecedented lows.


arctic storm august 2012

The storm's powerful winds caused drastic loss of Arctic sea ice: due to increased wave action, fragmenting of ice into smaller pieces, the pushing of ice into warmer waters, and the mixing up of warmer waters from beneath the ice. See: neven1.typepad.com



arctic ice cover sept


Sea Ice Extent, Sept 16, 2012. Via: EUMETSAT saf.met.no
The Northwest Passage was completely ice free until a few days prior to this image. The East Siberian Sea ice has completely disappeared - this has never been seen by satellite before.




Arctic ice melt 'like adding 20 years of CO2 emissions'

Loss of Arctic ice is effectively doubling mankind's contribution to global warming, ice scientist Professor Peter Wadhams has told BBC Newsnight.
White ice reflects more sunlight than open water, acting like a parasol.
Melting of white Arctic ice, currently at its lowest level in recent history, is causing more absorption.

Prof Wadhams calculates that this increased absorption of the sun's rays is "the equivalent of about 20 years of additional CO2 being added by man".

The Cambridge University expert says that the Arctic ice cap is "heading for oblivion".
neven1.typepad.com





Jennifer Francis, Rutgers University.

The "Arctic Paradox" was coined during recent winters when speculations arose that the dramatic changes in the Arctic may be linked to severe snowstorms and cold temperatures in mid-latitudes, particularly along the U.S. east coast and in Europe. Recent studies have illuminated these linkages. Evidence is presented for a physical mechanism connecting Arctic Amplification -- the enhanced warming in high northern latitudes relative to the northern hemisphere -- with the frequency and intensity of several types of extreme weather events in mid-latitudes, such as droughts, floods, heat waves, and cold spells.


Arctic Ice thickness - last 30 days  - www7320.nrlssc.navy.mil

See a 30 day animation of sea ice melt here: arctic.atmos.uiuc.edu




REPORT:
"The recent shift in early summer Arctic atmospheric circulation"
Key Points
  • There is an apparent sustained shift in early summer Arctic winds since 2007
  • Such Arctic changes are linked to increased North American atmospheric blocking
  • Highlights potential connectivity of Arctic climate and mid-latitude weather
www.agu.org

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