| Summary: | Ammonia (NH<sub>3</sub>) is an important precursor of secondary inorganic aerosols that affect air quality and human health. Livestock production is an essential source of NH<sub>3</sub> emissions, which exceeded half of the total NH<sub>3</sub> emissions in China. However, our understanding of the livestock point NH<sub>3</sub> emissions is still limited, due to the lack of both monitoring and statistical data. In this study, we established a satellite-based approach to estimating livestock point NH<sub>3</sub> emissions by combining satellite observations and digital maps of points-of-interest (POI). Taking a case study in Hebei province over China, 1267 livestock points were identified. The point livestock NH<sub>3</sub> emissions in 2020 ranged from 16.8 to 126.6 kg N ha<sup>−1</sup> yr<sup>−1</sup>, with an average emission of 42.0 kg N ha<sup>−1</sup> yr<sup>−1</sup>. The livestock NH<sub>3</sub> emissions in Hebei showed an overall increasing trend, with a growth rate of 5.8% yr<sup>−1</sup> between 2008 and 2020. In terms of seasonal changes, high livestock NH<sub>3</sub> emissions mainly occurred in spring and summer, while low NH<sub>3</sub> emissions were generally in autumn and winter. Satellite-derived point livestock NH<sub>3</sub> emissions in Hebei were 2–4 times that of bottom-up NH<sub>3</sub> emissions (EDGAR), suggesting that current used bottom-up emissions underestimated point livestock NH<sub>3</sub> emissions. This study proposed a framework for the satellite-based estimation of livestock NH<sub>3</sub> emissions, which is of great significance for relevant N management and NH<sub>3</sub> emission reduction policy formulation.
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