Earth system modeling of mercury using CESM2 – Part 1: Atmospheric model CAM6-Chem/Hg v1.0

Abstract. Most global atmospheric mercury models use offline and reanalyzed meteorological fields, which has the advantages of higher accuracy lower computational cost compared to online models. However, these products need past and/or near-real-time observational data cannot predict future. Here, we an component with tropospheric stratospheric chemistry (CAM6-Chem) state-of-the-art climate model CESM2, adding new species simulating cycling. Our results show that newly developed is able simulate observed spatial distribution total gaseous (TGM) in both polluted non-polluted regions high correlation coefficients eastern Asia (r=0.67) North America (r=0.57). The calculated lifetime TGM against deposition 5.3 months reproduces interhemispheric gradient a peak value at northern mid-latitudes. HgII wet over (r=0.80) captures magnitude maximum Florida Peninsula. simulated fluxes present pattern low northwest southeast. line seasonal variations mid-latitudes as well Southern Hemisphere, shows amplitude. We further go into factors affect find Hg0 dry dry/wet depositions contribute it.