Improving estimates of pollution outflow at Gosan using 222Rn

Abstract

The best understanding of climatic, ecological and health effects from increasing Southeast Asian emissions will likely be achieved by models coupled to detailed emission inventories and remote sensing data. To improve model accuracy and forecast horizons, careful evaluation against appropriate observations is essential. To minimize the chance of misleading comparisons, it is important to ensure ground-based reference observations are well matched with the model output, especially regarding fetch regions and scales of observation. To quantify upstream emissions based on ground-based observations it is necessary to: (i) understand the measurement “footprint”, (ii) identify observations most representative of air that has been in good contact with the surface over which it has travelled, and has not been significantly diluted by fronts or deep convection in transit, (iii) ensure observations are representative of the whole boundary layer (BL), (iv) minimize the influence of local emissions, (v) characterize changes in mixing depth, and (vi) characterize evolving “background” concentrations.