Enhanced atmospheric ammonia (NH3) pollution in China from 2008 to 2016: Evidence from a combination of observations and emissions

Shenghai Chen; Miaomiao Cheng; Zheng Guo; Wen Xu; Xiaohui Du; Yu Li

doi:10.1016/j.envpol.2020.114421

Enhanced atmospheric ammonia (NH₃) pollution in China from 2008 to 2016: Evidence from a combination of observations and emissions

Environ Pollut. 2020 Aug;263(Pt B):114421. doi: 10.1016/j.envpol.2020.114421. Epub 2020 Mar 26.

Authors

Shenghai Chen¹, Miaomiao Cheng², Zheng Guo³, Wen Xu⁴, Xiaohui Du⁵, Yu Li⁶

Affiliations

¹ State Key Laboratory of Remote Sensing Science, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China; Beijing Engineering Research Center for Global Land Remote Sensing Products, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China; Faculty of Geomatics, East China University of Technology, Nanchang, 330013, China.
² State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
³ Division of Remote Sensing Data Application, National Satellite Meteorological Centre, Beijing, 100081, China.
⁴ College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions of MOE, China Agricultural University, Beijing, 100193, China. Electronic address: hi.xuwen@163.com.
⁵ State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; College of Water Sciences, Beijing Normal University, Beijing, 100875, China.
⁶ State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), Beijing, 100083, China.

PMID: 32244123
DOI: 10.1016/j.envpol.2020.114421

Abstract

The increase of gaseous ammonia (NH₃) concentration in the atmosphere significantly impacts the regional air quality, human health, and the nitrogen cycle of ecosystems. This study aims to verify the reanalyzed product of IASI NH₃ (the ANNI-NH₃-v2.1R-I, hereafter referred to as IASI_NH₃_R) and to analyze the spatial and temporal characteristics of atmospheric NH₃ during 2008-2016 and its underlying influencing factors. Our results show a good agreement between spatial pattern and temporal (annual and monthly) trend of the satellite-derived surface NH₃ concentrations and the measured near-ground NH₃ measurements over different land covers in Eastern China, suggesting the IASI_NH₃_R product can be used to investigate spatial and temporal trends of atmospheric NH₃ concentration. The annual mean NH₃ column concentrations peaked in the North China Plain (averaged 12 × 10¹⁵ mol cm^-2 yr^-1) and showed a significant increasing trend at a rate of 0.6 × 10¹⁵ mol cm^-2 yr^-1 during the entire period, which can be ascribed to densely populated, intensive agricultural activities and substantial reduction of SO₂ and NO₂ emissions since 2011. The NH₃ column concentrations show a slight increase in winter in most regions of China, probably due to less precipitation amount and increased uncertainty for lower NH₃ columns and the thermal contrast (TC). A large seasonal variation of NH₃ column concentrations was observed, with the highest values in summer and the lowest in autumn. Such seasonal variation is mainly affected by seasonal differences in NH₃ emissions and meteorological conditions. Our results suggest that the current control measures effectively decreased SO₂ and NO₂ pollution but are not yet apparent in the mitigation of atmospheric NH₃ pollution, which also merits more attention considering that no effective measures are being implemented for NH₃ emission control at a regional or national scale in China.

Keywords: Air pollution; Ammonia; Emission control; Satellite observation; Spatio-temporal variation.

MeSH terms

Air Pollutants / analysis*
Air Pollution / analysis*
Ammonia / analysis
China
Ecosystem
Environmental Monitoring
Humans

Substances

Air Pollutants
Ammonia