J1.11
Global and regional indirect effects of aerosols appeared in modeling and satellite remote sensing
Teruyuki Nakajima, Univ. of Tokyo, Kashiwa, Chiba, Japan; and T. Takemura, A. Higurashi, T. Y. Nakajima, and K. Suzuki
Various sensitivity factors, Bq, of aerosol-cloud interaction effects are studied to evaluate the strength of aerosol indirect effects, when the correlation between aerosol number, Na, and a cloud parameter, q, is expressed as dq = Bq x dNa/Na. The statistics are obtained from satellite remote sensing results of aerosol and cloud parameters such as the optical thickness and a size index, and from model simulation results using MIROC general circulation model plus SPRINTARS aerosol model and also using a non-hydrostatic bin cloud model. It is found that POLDER type remote sensing method gives us a very small sensitivity factor for radiative forcing (q= radiative forcing), Br= -0.6 W/m2, as compared AVHRR and MODIS results, Br= -4.3 W/m2. We found a similar sensitivity parameter for the cloud fraction of low-level clouds over the Atlantic Ocean as Bn= 0.15 from AVHRR, and Bn= 0.12 from MODIS given by Yoram Kaufman's group, but we have much small factor for the globe as Bn= 0.03 from AVHRR. These results suggest that there are large uncertainties in the estimation of the sensitivity factor depending on satellite observation methods, and also there is a large dependence on the location of the globe. We like to discuss implications of the large variety of values of sensitivity factors using satellite remote sensing and model simulation results.
Joint Session 1, Indirect effects (Joint with 12th Conference on Atmospheric Radiation & 12th Conference on Cloud Physics)
Tuesday, 11 July 2006, 1:30 PM-5:00 PM, Ballroom AD
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