Estimation of emissions from biomass burning in China (2003–2017) based on MODIS fire radiative energy data

Lifei Yin,Pin Du,Mingxu Liu,Tingting Xu,Yu Song,Minsi Zhang

doi:10.5194/bg-16-1629-2019

Abstract

Abstract. Biomass burning plays a significant role in air pollution and climate change. In this study, we used a method based on fire radiative energy (FRE) to develop a biomass burning emission inventory for China from 2003 to 2017. Daily fire radiative power (FRP) data derived from 1 km MODIS Thermal Anomalies/Fire products (MOD14/MYD14) were used to calculate FRE and combusted biomass. Available emission factors were assigned to four biomass burning types: forest, cropland, grassland, and shrubland fires. The farming system and crop types in different temperate zones were taken into account in this research. Compared with traditional methods, the FRE method was found to provide a more reasonable estimate of emissions from small fires. The estimated average annual emission ranges, with a 90 % confidence interval, were 91.4 (72.7–108.8) Tg CO2 yr−1, 5.0 (2.3–7.8) Tg CO yr−1, 0.24 (0.05–0.48) Tg CH4 yr−1, 1.43 (0.53–2.35) Tg NMHC yr−1, 0.23 (0.05–0.45) Tg NOx yr−1, 0.09 (0.02–0.17) Tg NH3 yr−1, 0.03 (0.01–0.05) Tg SO2 yr−1, 0.04 (0.01–0.08) Tg BC yr−1, 0.27 (0.07–0.49) Tg OC yr−1, 0.51 (0.19–0.84) Tg PM2.5 yr−1, 0.57 (0.15–1.05) Tg PM10 yr−1, where NMHC, BC, and OC are nonmethane hydrocarbons, black carbon, and organic carbon, respectively. Forest fires are determined to be the primary contributor to open fire emissions, accounting for 45 % of the total CO2 emissions (average 40.8 Tg yr−1). Crop residue burning ranked second place with a large portion of 39 % (average 35.3 Tg yr−1). During the study period, emissions from forest and grassland fires showed a significant downward trend. Crop residue emissions continued to rise during 2003–2015 but dropped by 42 % in 2015–2016. Emissions from shrubland were negligible and little changed. Forest and grassland fires are concentrated in northeastern China and southern China, especially in the dry season (from October to March of the following year). Plain areas with high crop yields, such as the North China Plain, experienced high agricultural fire emissions in harvest seasons. Most shrubland fires were located in Yunnan and Guangdong provinces. The resolution of our inventory (daily, 1 km) is much higher than previous inventories, such as GFED4s and GFASv1.0. It could be used in global and regional air quality modeling.

Highlights

Biomass burning is an important source of gaseous and particulate matter emissions to the troposphere (Crutzen et al, 1979; Seiler and Crutzen, 1980)
In China, the annual amount of crop residue burned in fields estimated by Streets et al (2003) was 110 Tg, accounting for 44 % of all crop residue burned in Asia, leading to substantial pollutant emissions
Mehmood et al (2018) calculated the mean emission of CO2 for the period of 2002–2016 as 160 Tg yr−1 by using data derived from the Fire INventory from NCAR version 1.5 (FINNv1.5), which was established by the fire count method (Wiedinmyer et al, 2011)

Summary

Introduction

Biomass burning is an important source of gaseous and particulate matter emissions to the troposphere (Crutzen et al, 1979; Seiler and Crutzen, 1980). Studies statistically evaluated fire emissions in China with results of annual CO2 emissions of 68–150 Tg from crop residue burning (Ni et al, 2015; Huang et al, 2012; Li et al, 2016b) and 3–40 Tg from forest fires (Lu et al, 2006; Yan et al, 2006). This approach produced emission estimates at a coarse resolution that cannot be used for detailed analysis of spatiotemporal patterns. The fire count method is likely to overestimate the burned area of crop residue burning, and these fires are not detected efficiently by the available burned area algorithms due to the small areas and intermittency (Song et al, 2009)

Methods

Results

Conclusion