1-km resolution inversion of NOx emissions based on satellite constrained by geodata

High-resolution spaceborne emission inversions play a crucial role in independent emission monitoring, small-scale pollution modelling, and exposure estimation. However, spaceborne emission inversion at 1-km resolution is still a challenge due to the insufficiency of satellite observations, along with limitations such as computational costs and meteorological data. The spatial resolutions of existing satellite-based NO₂ observations (e.g. TROPOMI: nadir pixel of ~3.5×5.5 km²) fall short in capturing spatial features at 1-km resolution. Here we develop an innovative technique to integrate high-resolution geodata in emission inversions. This technique introduces constraints based on geodata associated with emissions to inversions independent of predefined downscaling schemes. Our inversions show advanced results of NOx emissions with detailed spatial patterns at small scale, especially for sources relevant to traffic and marine shipping which are of large uncertainties in current inventories.