Both emiss-opt and chem-opt options in WRF-Chem can be used for simulating wet deposition, but they have different capabilities and are suited for different purposes.

EMISS-OPT: This option in WRF-Chem simulates the emission, transport, and removal of aerosols and gases, but it does not include the chemistry of aqueous phase processes such as cloud chemistry. It is therefore not well-suited for simulating aqueous phase chemistry and wet deposition associated with cloud scavenging.

CHEM-OPT: This option in WRF-Chem includes aqueous phase chemistry, which allows for the simulation of wet deposition associated with cloud scavenging and below-cloud scavenging. It includes the simulation of chemical reactions and phase transfers in cloud and rainwater, and the deposition of particles and gases through both below-cloud scavenging and cloud scavenging.

Given your interest in simulating both aerosol and gas wet deposition, as well as aqueous phase chemistry, it seems that the CHEM-OPT option would be more appropriate for your purposes.

However, it is important to note that the CHEM-OPT option is computationally more expensive than EMISS-OPT, as it includes additional processes such as cloud and rainwater chemistry. Therefore, it may require more computational resources and longer simulation times.

It is also important to note that successful implementation of the CHEM-OPT option may require detailed input data, such as cloud and rainwater chemistry measurements, and careful consideration of model parameterization choices.

Kaushik Shandilya

Dear Kaushika,

So many thanks for your help and explanation. However, I meant which choice of these options are the best combination to simulate wet deposition.

Kind regards,