Spatio-temporal variations in SO2 and NO2 emissions caused by heating over the Beijing-Tianjin-Hebei Region constrained by an adaptive nudging method with OMI data

The Beijing-Tianjin-Hebei (BTH) region in China suffers from heavy air pollution, especially in heating period. In this work, SO2 emissions over the BTH region are determined using an adaptive “nudging” constrained method and a variational processing technique based on Ozone Monitoring Instrument (OMI) satellite data and surface measurement data collected in 2015. The intensity and influence of SO2 are significantly greater during the heating season than those during the non-heating season. Increases in SO2 emissions in the northern areas of the BTH region are larger than those in the southern part. And significant increases in SO2 emissions occur mainly in suburban and rural areas. The large amounts of bulk coal burning in the suburban and rural areas could cause significant regional air pollution.292