1. Significant contributions of combustion-related sources to ammonia emissions
- Author
-
Chen, Zhi-Li, Song, Wei, Hu, Chao-Chen, Liu, Xue-Jun, Chen, Guan-Yi, Walters, Wendell W., Michalski, Greg, Liu, Cong-Qiang, Fowler, David, Liu, Xue-Yan, Chen, Zhi-Li, Song, Wei, Hu, Chao-Chen, Liu, Xue-Jun, Chen, Guan-Yi, Walters, Wendell W., Michalski, Greg, Liu, Cong-Qiang, Fowler, David, and Liu, Xue-Yan
- Abstract
Atmospheric ammonia (NH3) and ammonium (NH4+) can substantially influence air quality, ecosystems, and climate. NH3 volatilization from fertilizers and wastes (v-NH3) has long been assumed to be the primary NH3 source, but the contribution of combustion-related NH3 (c-NH3, mainly fossil fuels and biomass burning) remains unconstrained. Here, we collated nitrogen isotopes of atmospheric NH3 and NH4+ and established a robust method to differentiate v-NH3 and c-NH3. We found that the relative contribution of the c-NH3 in the total NH3 emissions reached up to 40 ± 21% (6.6 ± 3.4 Tg N yr−1), 49 ± 16% (2.8 ± 0.9 Tg N yr−1), and 44 ± 19% (2.8 ± 1.3 Tg N yr−1) in East Asia, North America, and Europe, respectively, though its fractions and amounts in these regions generally decreased over the past decades. Given its importance, c-NH3 emission should be considered in making emission inventories, dispersion modeling, mitigation strategies, budgeting deposition fluxes, and evaluating the ecological effects of atmospheric NH3 loading.
- Published
- 2022