How well can we predict the unpredictable climate? Environment and security seminar, Oslo, 8 Dec Prof. Olav Orheim, Director, Norwegian Polar Institute How well can we predict the unpredictable climate? Environment and security seminar, Oslo, 8 Dec Prof. Olav Orheim, Director, Norwegian Polar Institute

Content of this presentation The overall climate picture –Uncertainty - the ”loaded dice” and can we insure against the risk? –Lack of knowledge and IPY

We are the first generation that influences global climate and the last generation to escape the consequences Norwegian Glacier Museum, 1991

Natural climate changes _ CO 2 level in 2004

CO 2 leads CH 4 which leads temp. Source: EPICA team. Nature, 10 June 2004

Source: Meteorologisk Institute, Oslo, November 2004

Predicting the unpredictable climate The greenhouse effect is certain - without it no humans! Uncertainties for the future include: Balance between natural and human effects, including variations in output of the sun. Feedbacks, including clouds, albedo, snow and ice, vegetation, carbon storage, atmosphere/ocean interaction Averages can be predicted – not single events. This is the ”loaded dice”

Comparing observed and projected changes Winter (D,J,F) 1990’s -2090’s Winter (D,J,F)

Southern Europe July/August temperatures, as deviation from mean. * below is 2003 summer Observed (black) and climate models (colour) Source: Stott, Stone, Allen. Nature, 2. Dec. 2004

Daily mortality, B-W, Germany Per people. Note 2003 heatwave Source: Schär and Jendritzky, Nature 2 December B-W = Baden-Wurttemberg, Sozialministerium

The Greenland Ice Sheet Satellite Data Documents the Changes

Insuring against climate change? Association of British Insurers in October 2004: ”Global economic losses caused by natural weather catastrophies have increased 10-fold over past 40 years.” ”Damage now increasing 2-4%/year from changing climate.” Mainly floods, storms,avalanches Sea level now rising 2 mm/year, Holland sinks 2 cm/year The Pentagon weather nightmare (“Abrupt climate change”) “The day after tomorrow”

Understanding and Projecting the Changes in the Oceanic Conveyor Belt is a Critical Question for Science

Note Downward Trend beginning in late 1970’s Nine (9) Models Source: Cubasch et al. 2001

Observations so far show no weakening of the ocean transport

International Polar Year An intense burst of activity combining, ground observations and satellites, to give a data set for improving climate models and predictions A permanent legacy of improved Arctic cooperation Arctic/Antarctic ocean teleconnections – thermohaline circulation and the climate of lower latitudes