Hello everyone,
I used different versions of CMAQ to simulate elemental mercury concentrations under various conditions in January 2022 (as shown in the figure below, with the format: CMAQ version_initial media mercury concentration_deposition mode_HGBIDI on/off). I found that the simulated concentrations at background sites (<0.5 ng/m³) are much lower than the observed concentrations (1–2 ng/m³). Could you please advise what might be causing this discrepancy? My main configuration information are as follows:
- Meteorological Inputs: WRF v3.9.1
- CMAQ Version: v5.4 / v5.5
- Emission inventory: EDGAR 2022
- DepMod: Stage / m3dry
- Mechanism: cb6r5hap_ae7_aq
- NZ (Vertical Layers): 14
- HGBIDI: Y / N