Climatology of black and organic carbon particles from 1950 to 2100
Résumé
Increasing interest for carbonaceous aerosol studies is due to the recognized effect of such particles on regional and global radiative balance and climate. Recent calculations (Jacobson et al.,2002) have shown for example that reduction of black carbon (BC) and organic carbon (OC) particle emissions by fossil fuel combustions especially diesel combustions, may slow the global warming more efficiently that any reductions of carbon dioxide. Such studies rely on very different existing BC inventories with different budgets (Penner et al., 1993, Cooke and Wilson, 1996, Liousse et al., 1996, Cooke et al., 1999, Lavoué et al., 2000) while other developments for the global (Bond, Shulz or Chin works) and regional scales (Streets, Reddy, Michel, Liousse works) are currently underway. Yearly global BC emissions from Bond is roughly half of those given by Cooke et al., 1999. In this work, some intercomparisons conducted between different existing inventories will be firstly presented for a few specific years focusing on the main reasons for such differences. Then, changes of fossil fuel BC emissions will be scrutinized for the 1950-2100 period. From 1950 to present, the BC inventory which has been used, has been created following Cooke et al. (1999) including new recent developments. Projections for 2020 and 2100 have been obtained by using fuel consumption data and population change proposed by IPCC report for two extreme scenarii. For any situation from the past to future, emission factors for carbonaceous aerosols were carefully adapted with attention to the nature of fuel, fuel usage and partition between transport, industrial and domestic sectors. The state of development of each country was also taken into account. These source inventories were then introduced in the European TM3 model, a 3D global off-line transport model. Global trends for modeled BC concentrations have been studied with focus on some relevant sites located in China, India and Europe. An inventory of organic particles has been also tentatively introduced for the same period and the effect of these aerosols studied. At last, radiative forcing calculation has been performed for modeled fossil fuel carbonaceous aerosol for different years (1970, 1980, 1990, 2020 and 2100). To conclude it is important to mention that scenarii based on IPCC tools could not be adapted to biomass burning emissions. Indeed, we have scrutinized annual trends of carbonaceous aerosol emissions from african biomass burning and their subsequent modeled impact with comparisons with TOMS data. For the 1980 decade and the 2000 year, several inventories were derived from satellite data. Strong interannual variability has shown complex relationships with human activities and climate, giving some clue for past and future source inventory exercices.
