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Calculation of emis_vol in emissions_driver.F

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I am using WRF-CHEM 4.0.1 to simulate volcanoes and noticed a potential bug.

By my understanding, emis_vol is calculated in convert_emiss.F for each ash size bin based on the size distributions in prep_chem_sources, depending on the type of volcano. For example:


If emiss_ash_height is specified > 1 in the namelist, emis_vol is recalculated based on the new ash height in emissions_driver.F. However, in emissions_driver, size_dist is not used. Rather, a value is hard coded as follows:


The hard-coded size_dist values appear to match those specified in volc_emissions.f90 (in prep_chem_sources) for S0 or S2 volcanoes (Although the .4 for vash3 should be a .04??). Thus, if emiss_ash_height is specified in the namelist for a volcano type other than S0 or S2, emis_vol will be recalculated incorrectly.

My suggestion is to pass "size_dist" into emissions_driver in order to replace the hard-coded values with the correct values from prep_chem_sources.