MOZART+MOSAIC mechanism: what variable "sulf" is in the output file and why "MSA" diasppear in the mechanism

[Qiwei]

Hello,

I'm using MOZART+MOSAIC in WRF-Chem and get my ouput file. Since I care more about species of Sulfur, (1)I want to figure out what is "sulf" in the file. 

Below is the information about "sulf" in the registry.chem:

state   real   sulf        ikjftb   chem        1         -   i0{12}rhusdf=(bdy_interp:dt)  "sulf"          "SULF mixing ratio"        "ppmv"

Below is the information about "sulf" in the ./chem/KPP/mechanisms/mozart_mosaic_4bin/mozart_mosaic_4bin_wrfkpp.equiv:

name in wrf        name in kpp

SULF                    SO4

As you can see, its unit is ppmv, so I used to think it's gaseous sulfuric acid, but I didn't find any clear explanation.

if  "sulf" means sulfate  , how is it different from "so4_a01, so4_a02, so4_a03, so4_a04" which derive from MOSAIC?

(2) In Zaveri's article about MOSAIC, it said MOSAIC include methanesulfonate. But in the mozart_mosaic_4bin.spc or mozart_mosaic_4bin.eqn file, there is no MSA in this file, nor in my output file. I wonder why it diappear in the MOZART+MOSAIC.

Thanks for your patience.