Spatial variation of aerosol properties over Europe derived from satellite observations and comparison with model calculations
[摘要] Aerosol optical depths (AOD) andAngström coefficients over Europe were retrieved using data from the ATSR-2 radiometer on board the ESA satellite ERS-2, for August 1997. Takingadvantage of the nadir and forward view of the ATSR-2, the dual view algorithm was usedover land to eliminate the influence of the surface reflection. Over sea the AOD was retrievedusing only the forward observations. Retrieved aerosol optical properties are in goodagreement with those from ground-based sunphotometers. The AOD and Angströmcoefficients together yield information on the column integrated effective aerosol distribution.
Observed regional variations of the AOD andAngström coefficient are related to anthropogenic emissions of aerosol precursors such asSO2 and NOx in the major European industrial and urban areas, and their subsequent transformation into the aerosol phase. Theinfluence of anthropogenic aerosols such as ammonium sulphate and ammonium nitrate onthe total AOD is estimated using a regional chemistry transport model. Sulphate is estimatedto contribute from 15% in very clean areas to 70% in polluted areas, the contribution of nitrateis between 5% and 25% over most of Europe. This paper shows the great importance ofnitrate in summer over The Netherlands.
