Un point de vue multifractal sur l'évolution climatique

A multifractal point of view on climatological evolution

¹ UMR Sisyphe, Ecole des Mines de Paris, 35 rue St Honoré, 77305 Fontainebleau
² LMM, Université P. & M. Curie, 4 Place Jussieu, 75252 Paris cedex 05
³ Météo-France, 1 Quai Branly, 75007 Paris
⁴ UMR Sisyphe, LGA, Université P. & M. Curie, 4 place Jussieu, 75252 Paris cedex 05
⁵ Physics dept., McGill U., 3600 University St, Montreal, Que. H3A 2T8, Canada
⁶ Ecole Nationale de la Météorologie, avenue Coriolis, 31057 Toulouse

Auteur de correspondance : hubert@cig.ensmp.fr

Abstract

The global warming assumption has not yet been convincingly substantiated from hydrometeorogical data analysis. In fact, as the atmosphere and the hydrosphere are highly non linear systems, one cannot expect a linear response to an increase of green house gas concentration because there exists various interactions and feedbacks at different scales between these systems and between their components. Before any prognosis about climate change it is rather indispensable to have a better knowledge of its natural variability. In any case, it will be extremely difficult or even fallacious to separate the anthropogenic and natural variability as it is likely that they strongly interact. To overcome such difficulties we argue that one has to keep as close as possible to the non linear physics of the involved phenomena. This is the objective of a multifractal analysis, which is both multiscale and multiintensity, of the available data.