Ola M. JohannessenNansen Environmental and Remote Sensing Center

Bergen, Norway

Arctic Climate – Present and Future

20 September 2012Longyearbyen, Svalbard

Onozaki, Journal of Health Science, 2009

Onozaki, Journal of Health Science, 2009

Ice concentration

Johannessen et al. 2004

Climate-model simulation of ice concentration due to CO2 doubling

80% decrease

Summer

Sea ice:

2005

Winter

20% decrease

2085

2005 2085

The simulated surface circulation between 1970 and 2000

Gao, … , Johannessen, 2009

The simulated surface circulation between 2050 and 2080 under the global warming senario

Gao, … , Johannessen, 2009

Temperature

Johannessen et al. 2004

Annual temperature/ice extent

Modified from Johannessen et al. 2004

70-90oN annual SAT

• 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/

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/

http://arctic-roos.org/

http://arctic-roos.org/

http://arctic-roos.org/

Arctic Sea Ice Area: yearly 1979 - 2008

Johannessen and Ivanova 2011 (unpublished)

The ice breaker Gergiy Sedov In drift 1937-40

Kwok and Rothrock, 2009

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 mapThe 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) 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

a b

c

Arctic Sept Sea Ice Extent

Stroeve et al. 2007

Red: observedBlack: model esemble

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

Wang and Overland, 2009

Green: observed, black: modeled, blue: B1, red: A2, shading +/- 1 s.d.

Annual Sea Ice Extent

Johannessen AOSL, 2008

Johannessen 2012 (unpublished)

Johannessen 2012 (unpublished)

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