J. Phys. IV France 12 (2002) Pr10-19
Global warming 2001A. Berger
Université Catholique de Louvain, lnstitut d'Astronomie et de Géophysique G. Lemaître, chemin du Cyclotron 2, 1348 Louvain-la-Neuve, Belgium
2001 was the second-warmest year over the last 150 years. It was 0.43°C above the 1961-1990 global average, just behind the record of 1998 with its 0.59°C above the normal. In parallel, CO 2 has increased from 280 to 370 ppmv since the Industrial Revolution, at a rate 100 times faster than over the last 20 000 years. In its Third Assessment Report, the Intergovernmental Panel on Climate Change (IPCC) states clearly that "an increasing body of observations give a collective picture of a warming world and other changes in the climate system" and that "there is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities". Comparison of model results with present-day climatic observations and past climate reconstructions allows to conclude that the models capture relatively well both the natural climatic variations and the impact of man's activities on climate. This makes possible to draw conclusions from modeling results obtained for the next century. The globally averaged surface temperature is projected to increase by 1.4 to 5.8°C over the period 1990 to 2100 and sea level to rise by 9 to 88 cm for the full range of the IPCC scenarios.
© EDP Sciences 2002