OMI/Aura, SCIAMACHY/Envisat and GOME2/MetopA Sulphur Dioxide Estimates; the case of Eastern Asia

Abstract

The EU FP7 Monitoring and Assessment of Regional air quality in China using space Observations, Project Of Long-term sino-european co-Operation, MarcoPolo, project focuses on deriving emission estimates from space. Long term satellite observations of suphur dioxide, SO2, over the greater China area from the SCIAMACHY/Envisat, GOME2/MetopA and OMI/Aura missions are compared and their relative strong points and limitations are discussed. Rigorous spatiotemporal statistical analysis based on novel analysis techniques [Fioletov et al., 2011; 2013] is performed for each data set in order to reduce noise and biases and enhance pollution signals in satellite datasets. Furthermore, identification of point sources such as power plants, smelters and urban agglomerations, as well as definition of their relative contribution to the regional SO2 levels, form the main findings of this investigation. Comparison of different satellite datasets and their post-processed products with ground based MaxDOAS SO2 meas urements in Xianghe, China, located at ∼50 km southeast of downtown Beijing, helps validate the satellite datasets.