Based on the remote sensing data of NASA Landsat satellite, an algorithm was designed to provide insights into the bare soil erosion over the plain area in Beijing. The PM10 and PM2.5 emission factors as well as the annual bareness wind erosion dust emissions were estimated for different districts in Beijing. As a result, the bare soil area of Beijing plain had reduced by about 600km2 between 1987 and 2016. Induced PM10 emissions by the wind erosion in Beijing plain were estimated of about 7591.7 tons in 2016, similar to the results reported by previous studies, with critical wind erosion in Daxing and Tongzhou Districts. However, significant seasonal variation of the bare soil erosion was indicated by further analysis of monthly and seasonal trends of meteorological parameters and bare soil area. The bare soil area data was derived from Landsat image, with a maximum of 4500km2 in February, and a minimum of 500km2 in August. With the improvement of the model, the monthly and quarterly cumulative emissions of PM10 was estimated to be 55175 tons and 39294 tons respectively. It's suggested that existing bare soil dust estimation method, consisting of analysis of annual variation of meteorological parameters, seemed to neglect the seasonal discrepancies of wind erosion process, leading to a great underestimation of wind erosion dust emissions of bare soil.
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