AOD trends during 2001–2010 from observations and model simulations
Abstract. The aerosol Optical Depth (AOD) trend between 2001–2010 is estimated globally and regionally from observations and from model simulations. The model is able to reproduce quantitatively the AOD trends as observed by MODIS satellite sensor, while some discrepancies are found when compared to MISR and SeaWIFS observations. Thanks to an additional simulation without any change in the emissions, it is shown that decreasing AOD trends over the US and Europe are due to decrease in the emissions, while over the Sahara Desert and the Middle East region the meteorological changes do play a major role. Over South East Asia, both meteorology and emissions changes are equally important in defining AOD trends. Additionally, decomposing the regional AOD trends into individual aerosol components reveals that the soluble components are the most dominant contributers to the total AOD, as their influence on the total AOD is enhanced by the aerosol water content.