Impact of aerosols from urban and shipping emission sources on terrestrial carbon uptake and evapotranspiration: A case study in East Asia

Overall, modeled gross primary productivity and evapotranspiration almost linearly increase with the all-species emission reductions, but their responses to emission-induced aerosol optical depth (AOD) changes show strong spatial variability resulting from combined radiation and temperature impacts. Using satellite-observation-constrained NOx emissions, modeled nitrogen species and AOD better match various measurements at some locations/times.

All-species and NOx-only emission adjustments lead to different gross primary productivity and evapotranspiration changes with AOD, especially over South Korea. This study demonstrates the importance of accurately quantifying emission impacts on atmosphere-biosphere interactions. Improving more species' emission inputs for Earth system models, including applying effective chemical data assimilation methods, is strongly encouraged.