Junhua YANG ,Shichang KANG*,2,3 ,Yuling HU ,Xintong CHEN,2 ,and Mukesh RAI,2

1State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences (CAS), Lanzhou 730000, China

2University of Chinese Academy of Sciences, Beijing 100049, China

3CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China

Table S1.The detailed information of the monitoring sites over South Asia.

Fig.S4.Seasonal variation trend of precipitation from the CRU dataset.

Fig.S5.Annual emissions of CO in the pre-monsoon.

Fig.S6.WRF-Chem simulated surface wind during different seasons.

Fig.S7.Seasonal variation of residential emissions of SO2 (the left row) and NOx (the right row).

Fig.S8.Deviation of pre-monsoon (the left row) and winter (the right row) secondary PM2.5 components from annual average,as calculated by (M -N)/N,where M and N were pre-monsoon (winter) and annual concentrations respectively.

Fig.S9.Deviation of pre-monsoon (the left row) and winter (the right row) primary PM2.5 components from annual average.

Fig.S10.O3 precursors (ppb) change due to South Asian biomass burning during pre-monsoon.

Fig.S11.Horizontal and vertical transport of black carbon (BC,μg/m3) and organic carbon (OC,μg/m3) from South Asian biomass burning to the TP.

Fig.S12.Aerosol precursors (ppb) change due to South Asian biomass burning during pre-monsoon.

Fig.S13.The contribution ratios (%) of South Asian biomass burning to NO2.

Fig.S14.Winter residential (a) and industrial (b) emissions of PM2.5.