Classifying and quantifying decadal changes in wet deposition over Southeast and East Asia using EANET, OMI, and GPCP

Abstract

South East and East Asia are regions which have undergone rapid economic development, contributing a significant amount of urban and biomass burning emissions. While the connections between emissions, deposition, and impacts on the Earth System are theoretically understood, they are observationally and ill-constrained, especially with respect to the effects of a changing climate and the Monsoon. This work shows the results of a new classification scheme and Asian-Wide monthly wet deposition product based upon 16 years of surface wet deposition observations and remotely sensed trace gas and precipitation measurements throughout South East and East Asia. Specific information corresponding to underlying driving and physical processes including in-situ processing, long-range transport, and local emission sources are all considered. Scientific findings are made specifically with respect to the increased impacts of urban-scale change, long-range transport, and enhanced deposition under moderate to low precipitation conditions. Previously accepted definitions of clean and polluted areas are challenged and updated based upon more detailed analysis of the observed physical and chemical relationships and simple models. The spatial and temporal distribution of the resulting modeled wet deposition is shown to impact the oceans more significantly, and regions of land not previously thought to be heavily impacted.