Considerable Unaccounted Local Sources of NO x Emissions in China Revealed from Satellite.
Hao KongJintai LinLulu ChenYuhang ZhangYingying YanMengyao LiuRuijing NiZehui LiuHongjian WengPublished in: Environmental science & technology (2022)
High-resolution (e.g., 5 km) emission data of nitrogen oxides (NO x = NO + NO 2 ) provide localized knowledge of pollution sources for targeted regulations, yet such data are lacking or inaccurate over most regions at present. Here we improve our PHLET-based inversion method to derive NO x emissions in China at a 5-km resolution in summer 2019, based on the TROPOMI-POMINO satellite product of nitrogen dioxide (NO 2 ) columns. With low computational costs, our inversion explicitly accounts for the effects of horizontal transport and nonlinear chemistry. We find numerous small-to-medium sources related to minor roads and small human settlements at relatively low affluence levels, in addition to clear emission signals along major transportation lines, consistent with road line density and Tencent location data. Many small-to-medium sources and transportation emissions are unclear or missing in the spatial distributions of four widely used emission inventories. Our emissions offer a unique reference for targeted emission control.
Keyphrases
- drinking water
- electronic health record
- high resolution
- big data
- municipal solid waste
- endothelial cells
- healthcare
- life cycle
- cancer therapy
- risk assessment
- contrast enhanced
- health risk assessment
- computed tomography
- mass spectrometry
- particulate matter
- single molecule
- artificial intelligence
- machine learning
- climate change
- induced pluripotent stem cells
- liquid chromatography