報告題目：Two decades of aerosol retrieval: observing the evolution of atmospheric composition from space
報 告 人：Prof. Gerrit de Leeuw
Professor Gerrit de Leeuw, a Professor on Satellite Remote Sensing of Aerosol Physical and Optical Properties at the Finnish Meteorological Institute (FMI), Finland and a visiting professor at RADI/CAS in Beijing and NUIST in Nanjing. He (co-) authored ca. 200 peer-reviewed research articles (H-index 40), 1 book. PI in 31 EU projects (4 as coordinator), 17 ESA projects (2 as coordinator, 1 as science leader) and Academy of Finland projects (2 as coordinator).
My work on satellite remote sensing of aerosol properties started in 1995 and the focus was soon on using the dual view available from the European Space Agency (ESA) Along Track Scanning Radiometers ATSR-2 on ERS-2 and AATSR on ENVISAT. Together these sensors span a period of 17 years of AOD observations, from 1995-2012. This time series provides useful information on the evolution of the AOD over different regions, in response to economic development and socio-economic conditions as well as measures to improve air quality. Awaiting the extension of this time series with information from the operational Sea and Land Surface Temperature Radiometers (SLSTR) on Sentinel-3, MODIS/Terra data have been used to create a two decadal time series. To do this, the ATSR and MODIS data sets have to be compared to understand observed differences. Taking AERONET sun photometer data as reference, it appears that, over China, ATSR slightly underestimates AOD whereas MODIS overestimated by a similar amount. This information shows that the data sets can be used together to provide information on the temporal evolution of the AOD, including both seasonal variation and long-term variations, with differences for different regions. An overview of these findings will be presented.