ABSTRACT
Biomass burning (BB), such as from agricultural crop residues, releases large amounts of air pollutants (e.g., PM2.5) lead to various human respiratory and general health problems when inhaled. In this chapter, we address the impacts of BB on the regional and long-range transport of PM2.5 in Northeast Asia, resulting from an intense in-field BB event in Northeast China during the autumn of 2014. The Community Multiscale Air Quality (CMAQ) model was used to conduct air quality simulations in 2014 over Northeast Asia. In the baseline simulation (Base), field BB emissions were derived from the Global Fire Emissions Database (GFED) v4.1s for 2014. The model reasonably captured the monthly mean PM2.5 mass concentrations. However, it underestimated concentrations in October, especially in Northeast China, where an intense agricultural waste burning occurred. Additional simulation with boosted BB emissions from agricultural waste burning (GFED_agri15) was attempted to address the underestimation of PM2.5 in Northeast China. The model performance in the GFED_agri15 case improved substantially and showed smaller biases and higher indices of agreement between simulated and observed values compared to the Base case. Also, to evaluate long-range transport of PM2.5 from BB sources in China toward Japan, CMAQ with Brute-Force method (CMAQ/BFM)-estimated BB contributions for the Base and GFED_agri15 cases were compared with Positive Matrix Factorization (PMF)-estimated BB contributions at the Noto Peninsula in Japan. The CMAQ/BFM-estimated contributions in the GFED_agri15 case were in greater agreement with the PMF-estimated contributions. Consequently, boosted BB emission (GFED_agri15) is preferable for simulating air quality in Northeast Asia, which could be deeply impacted from agricultural waste burning.
