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Leon Kuhn

New member
Dear users,

I am currently using WRF-Chem, version 4.2.2. In the WRFDA user manual

there is a section called "Aerosol/Chemical Data Assimilation", which says:

Aerosol/Chemical data assimilation capability is added in version 4.3. Currently it allows the assimilation of 6 types of surface measurements (PM2.5, PM10, O3, CO, NO2, SO2) with 3DVAR, which can provide the analyzed initial conditions for WRF-Chem. (...) The executable is still da_wrfvar.exe, but now it can take WRF-Chem’s initial condition file as the background (i. e., the ‘fg’ file) and perform the aerosol/chemical analysis in addition to the usual function for meteorological analysis. All related settings are in a new namelist section named wrfvarchem.

I want to realize this, in order to improve air quality predictions of a WRF-Chem simulation using surface observations of NO2 (and possibly O3).
It was mentioned in other posts in this forum, that WRFDA and WRF-Chem do not work together, however this user manual suggests otherwise. It is however quite unclear in what order and especially how to install WRFDA and WRF-Chem so that they run together. With WRF-Chem currently installed, is there a way to install WRFDA on top?

Best regards