European Latsis Prize 2001

Press contact: Jens Degett, ESF,  +33 (0)3 88 76 71 32

The 22 November the European Science Foundation will award this year’s European Latsis Prize to Professor André Berger from Institute of Astronomy and Geophysics Georges Lemaître at the Catholic University of Louvain, for his outstanding contributions to the understanding of the Ice Age cycle of climate. The prize ceremony will take place at Hotel Hilton in Strasbourg.

The European Latsis Prize, of a value of 100.000 Swiss Francs (68.000 €) is financed by the Latsis Foundation and awarded by the ESF to an individual or group who, in the opinion of their peers, has made the greatest contribution to a particular field of European research. The chosen field of the 2001 prize was ”Climate Research”.

Recognised for his outstanding contribution, nearly 30 years ago, to the understanding of our current Ice Age, Professor André Berger was the first to establish an accurate description of the variations of the astronomical factors which influence the global climate. Since then, André Berger has used his expertise to understand how the climatic fluctuations during ice ages are generated, using computer models of different complexity.

The orbital hypothesis of climatic change was first formulated by James Croll in the XIXth century and by Milutin Milankovitch in the early 1920’s. According to this theory the polar insolation in summer is the critical factor which determines the ice ages. When the snow from the previous winter can not melt it accumulates and creates a further cooling by reflecting the sunlight. This positive feedback eventually leads to the formation of persistent ice sheets. The later calculation by André Berger confirmed this theory, but showed also that the Earth’s climate has a more complex behaviour than the simple linear Milankovitch model.  Berger demonstrated that changes in the seasonal and latitudinal distributions of the daily insolation received by the Earth are much more significant than the changes in the Milankovitch half-year caloric seasons. Berger’s original work was indeed to recalculate the long-term variations of these astronomical parameters with an accuracy that is universally accepted today as definitive over more than one million years. He has also shown how these variations are influencing the amount of energy the Earth receives from the Sun and how they are reflected in proxy records of climate, as in global sea level and ice volume, since the Earth entered its current Ice Age some 2 to 3 Million years ago.

According to the astronomical data, we are at the beginning of an unusually long interglacial, a period which started about 6,000 years ago and would last for about 50,000 years. Such a length is really exceptional over the recent geological past and its probability can even be larger if the build-up of high CO2 level in the atmosphere continue due to uncontrolled man’s activities. The present CO2 concentration (370 ppmv) is already well above the values characterizing the last 400,000 years during which CO2 varied between 200 (during glacial) and 280 (during interglacial) ppmv. Higher CO2 levels, in the range of the IPCC scenarios, may even lead to an irreversible disappearance of the Greenland and western Antarctic ice sheets within the next thousands of years with a subsequent 12 m rise of sea level.

Press contact

Jens Degett
Head of Communication and Information, ESF
+33 (0)3 88 76 71 32

Issued 20.11.2001

Category: Media Centre, Press Releases 2001