Direct Radiative Effects Caused By Crop Burning Over the North China Plain During the Harvest Season

Abstract:

The north China Plain, a major agriculture zone with dense population, suffers from severe aerosol pollution for the open burning of wheat straw residue during Junes, the harvest season. This study updated the inventory of crop burning in June 2013 based on detailed census data and MODIS thermal anomalies/fire products and then investigated the direct radiative effects by using the fully coupled model WRF-Chem model over the North China Plain. The simulation results were compared well with the PM2.5 chemical compositions and meteorological data. The results indicated that open burning of wheat straw from the south to the north was the dominator to EC concentration during harvest seasons, which could reach 85.2ug/m³ during night. Contribution of crop burning to EC concentration could be as high as 92.2% in the pollution episode. The EC was estimated to produce positive radiative effects with + 6.1 W/m² at the top of atmosphere over the North China Plain. It is necessary for scientists and government to pay more attention to the pollution caused by the open burning of crop residue.