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Arctic Climate – Present and Future. Ola M. Johannessen Nansen Environmental and Remote Sensing Center Bergen, Norway. 20 September 2012 Longyearbyen , Svalbard. Onozaki, Journal of Health Science, 2009. Onozaki, Journal of Health Science, 2009.
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Arctic Climate – Present and Future Ola M. Johannessen Nansen Environmental and Remote Sensing Center Bergen, Norway 20 September 2012 Longyearbyen, Svalbard
Climate-model simulation of ice concentration due to CO2 doubling Sea ice: Winter 20% decrease 2085 2005 Summer 80% decrease 2085 2005 Ice concentration Johannessen et al. 2004
Gao, … , Johannessen, 2009 The simulated surface circulation between 1970 and 2000
Gao, … , Johannessen, 2009 The simulated surface circulation between 2050 and 2080 under the global warming senario
Temperature Johannessen et al. 2004
Annual temperature/ice extent 70-90oN annual SAT Modified from Johannessen et al. 2004
What is Arctic ROOS ? An association of 16 member institutions from 9 European countries with the aim to foster and develop Arctic components of Global Ocean Observing System • The background document was produced in 2005 by the EuroGOOS Arctic Task Team • Arctic ROOS is a contribution to the IPY project no. 379: "IPY Operational Oceanography for the Arctic Ocean and adjacent seas" coordinated by Prof. Ola M. Johannessen, endorsed by IPY 2006. • Arctic ROOS was established in December 2007 at the foundation meeting in Luleå, hosted by EuroGOOS and SMHI • S. Sandven from Nansen Center in Norway was elected chair and hosts the secretariat of Arctic ROOS http://arctic-roos.org/
Monitoring ice concentration from microwave satellites TOTAL ICE COVER = MULTI-YEAR ICE + FIRST-YEAR ICE 100% 90% 80% 70% 60% 50% 40% 30% 15% water land http://arctic-roos.org/
Arctic Sea Ice Area: yearly 1979 - 2008 Johannessen and Ivanova2011 (unpublished)
Cryosat-2 Launched – April 2010;Altitude - 717 km ; Inclination - 92 deg; Repeat cycles - 369 days with 30 day sub-cycle SIRAL – SAR/Interferometric Radar Altimeter (13.6 ГГц) Resolution 250 х 7 000 m CryoSat-2 is orbiting Earth at an unusually high inclination, reaching latitudes of 88° north and south.
Cryosat-2 ice thickness map The sea-ice thickness map for January and February 2011 shows thicker, rough, multi-year ice north of Canada and Greenland, stretching to the North Pole. Elsewhere in the Arctic the map reveals thinner, first year ice.
a b c a) Location of 689 ice thickness and freeboard measurements during the Sever aircraft landings on the Arctic sea ice in 1980s, where colors indicate thickness of level ice on runways; b) histogram of ice thickness on level ice (on runway) and on characteristic ice types around the landing sites (off runway), c) a scatterplot of ice thickness versus ice freeboard measurements on level ice. Alexandrov, …., Johannessen2010
Arctic Sept Sea Ice Extent Red: observed Black: model esemble Stroeve et al. 2007
All six models show rapid decline in the ice extent and reach ice-free summer before the end of the 21st century Wang and Overland, 2009
Annual Sea Ice Extent Green: observed, black: modeled, blue: B1, red: A2, shading +/- 1 s.d. Johannessen AOSL, 2008
Conclusions • Summer ice may disappear when CO2 concentration is 500ppmv • Today the CO2 concentration is increasing with 2.5 ppmv pr. year • If this increase continues the summer ice will disappear in about 40 years, ie in 2050