1. Ola M. Johannessen Nansen Environmental and Remote Sensing Center Bergen, Norway Arctic Climate – Present and Future 20 September 2012 Longyearbyen, Svalbard

3. Onozaki, Journal of Health Science, 2009

5. Ice concentration Johannessen et al. 2004 Climate-model simulation of ice concentration due to CO 2 doubling 80% decrease Summer Sea ice: 2005 Winter 20% decrease 2085 2005 2085

6. The simulated surface circulation between 1970 and 2000 Gao, …, Johannessen, 2009

7. The simulated surface circulation between 2050 and 2080 under the global warming senario Gao, …, Johannessen, 2009

8. Temperature Johannessen et al. 2004

9. Annual temperature/ice extent Modified from Johannessen et al. 2004 70-90 o N annual SAT

10. 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 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 http://arctic-roos.org/

11. Monitoring ice concentration from microwave satellites 100% 90% 80% 70% 60% 50% 40% 30% 15% water land TOTAL ICE COVER = MULTI-YEAR ICE + FIRST-YEAR ICE http://arctic-roos.org/

15. Arctic Sea Ice Area: yearly 1979 - 2008 Johannessen and Ivanova 2011 (unpublished)

17. The ice breaker Gergiy Sedov In drift 1937-40

19. Kwok and Rothrock, 2009

20. 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.

21. 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.

22. 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, …., Johannessen 2010 ab c

23. Arctic Sept Sea Ice Extent Stroeve et al. 2007 Red: observed Black: model esemble

24. 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

29. Green: observed, black: modeled, blue: B1, red: A2, shading +/- 1 s.d. Annual Sea Ice Extent Johannessen AOSL, 2008

30. Johannessen 2012 (unpublished)

32. Conclusions Summer ice may disappear when CO 2 concentration is 500ppmv Today the CO 2 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