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| « The future of our climate » |
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Jean Jouzel |
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During the last centuries, human activities have significantly modified the composition of the atmosphere in greenhouse gases. The use of fossil fuels (coal, oil,natural gas) is largely responsible for the large increase of the atmospheric content in carbone dioxide since the beginning of the industrial epoch (35% increase since 1850). During the same time, increase of methane exceeds 100%, and nitrogen oxide has increased by 15%. Although these gases are minor components of the atmosphere, such variations may modify the climate because they produce a noticeable increase of the greenhouse effect. Our community is now deeply convinced that the global warming observed during the last decades is due to these modifications. We claim that if no mitigation policies are adopted in order to substantially decrease emissions of greenhouse gases, global warming will continue during the XXI century, and beyond.
What do we undoubtly know and what are the uncertainties ? Why do we need to study paleoclimates. What will be the impacts of this climate warming and what could be mitigation options ? I will discuss these different questions in view of the last IPCC report, of ongoing negociations at the international level and of the propositions made in France as a follow-up of the "Grenelle de l'Environnement". |
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vendredi 30 janvier 2009 - 11:00 Amphithéâtre Henri Mineur, Institut d'Astrophysique de Paris |
| Page web du séminaire / Seminar's webpage |