A high-resolution inventory of air pollutant emissions from crop residue burning in China

Abstract. Crop residue burning is an important source of air pollutants and strongly affects the regional air quality and global climate change. This study presents a detailed emission inventory of major air pollutants from crop residue burning for the year of 2014 in China. Activity data were investigated for 296 prefecture-level cities, and emissions were firstly estimated for each city and then redistributed using 1-km resolution land use data. Temporal variation was determined according to the farming practice in different regions. The MODIS fire product was applied to verify the spatial and temporal variations of the inventory. Results indicates that the total emissions of BC, OC, PM_2.5, PM₁₀, SO₂, NO_X, NH₃, CH₄, NMVOC, CO and CO₂ from crop residue burning (including open and household fuel burnings) were estimated to be 0.16, 0.82, 2.30, 2.66, 0.09, 0.70, 0.14, 0.81, 1.70, 13.70 and 309.04 Tg, respectively. Rice, wheat and corn were the three major contributors, but their relative contributions varied with region and season. High emissions were generally located in the eastern China, central China and northeastern China, and temporally peaking in June and October relating with harvesting time. The spatially and temporal distributions agree well with the fire pixel counts from MODIS. Uncertainties were estimated using the Monte Carlo method. This study provides a useful basis for air quality modeling and the policy making of pollution control strategies.