README.aerosols

Background:

Aerosals are more complicated in CESM1.  Tauback (typically used for paleo simulations) is not available.  Christine Shields developed a new technique to define aerosols for user-specified geography within CESM1(CAM4/5).  Download the 2011 CCSM workshop presentation of her results.

Recommendation:  You can run with bulk aerosols, but that is very expensive.  A better alternative is use the procedure described below.

How to create a prescribed aerosol dataset for deep time paleo:

 
1. turn off prescribed aeorsols, use bulk, i.e. trop_bam
2. this gives us dust and sea salt (primary aerosols)
3. for bam: create zonal distributions of oxid, dms, bc, and oc and soil erodiablity based on land
   i.e., avg modern grid points over ocean (where appropriate), avg modern grid pts over land, give
   avg values to paleo 2d data forcing files over respective lat and land
4. create prescribed aerosol (radiative) set based on BAM run
5. create prescribed aerosol (deposition) based on run BAM run

 

For BAM run:

--(1) create forcing data w/ncl scripts

see cam.input_data_list for bulk aerosols:

don't need deposition velocity stuff unless using chemistry.
1) do nothing about depvel_monthly.nc, clim_soilw.nc, and season_wes.nc --not needed
2) do nothing to  do about regrid_vegetation.nc -- not needed

new datasets for:
1) oxid: oxid_1.9x2.5_L26_1850clim_c091123.nc
2) soil erod:  dst_48x96_c090203.nc
3) so2:  aerocom_SO2_vertical_1750.c080807.nc lat/mtns?
         aerocom_SO2_surface_1750.c080807.nc  lat/mtns?
4) so4:  aerocom_SO4_vertical_1750.c080807.nc
         aerocom_SO4_surface_1750.c080807.nc
5) CB1:  aerocom_CB1_1750.c080807.nc  (lat dist)
6) DMS:  aerocom_DMS_2000.c080417.nc (lat dist)
7) OC1:  aerocom_OC1_1750.nosoa.c080807.nc (lat dist)

create ncl scripts to read in template (default) file, and modify accordingly
details: see fis/cgd/ccr/shields/permian/ccsm4/atm/bulk_aero_files/data/README.whatidid

--(2) take output from BAM and create prescribed forcing aerosol (raditative)
      (from jf email)

        (a) ncra -h -v
lat,lon,lev,time,date,datesec,hyam,hybm,hyai,hybi,PS,P0,T,CB1,CB2,OC1,OC2,SO4,SOA,
DST01,DST02,DST03,DST04,SSLT01,SSLT02,SSLT03,SSLT04

       (b) then you concatenate all those into a single file (beware that sometime p0 becomes 0_

       (c) you probably need to overwrite date and time as those also get messed
          up with ncra.

        SCRIPT written: /fis/cgd/ccr/shields/permian/ccsm4/atm/presc_aero_files/aero_climo.csh

        (d) NOTE: does not need to be interpolated to fv2deg res (as default). model will accept
            any resolution, (eaton), and interp, on the fly, if necessary. normally all model
            configs use the fv2deg, but you can supply a file at the correct config resolution to
            begin with...              

** although in theory (d) is true, code currently buggy and the aero file doesn't
                   work,  use aero_climo_interp.ncl to put onto fv2deg grid. (march 4 2011). bug
                   reported to b.eaton and f.vitt.

--(3) branch basic default (BAM) run (or change in original) to include vars necessary for deposition
       to create aero dep file for prescribed aero run.
      (from jf email)

        (a) monthly avg hist needed:
        DF_CB1   (need to include in finc1)
        DF_CB2   (need to include in finc1)
        CB2SFWET  (default bam)
        DF_OC1    (need to include in finc1)
        DF_OC2    (need to include in finc1)
        OC2SFWET  (default bam)
        DST01DD   ("")
        DST01PP   ("")
        DST02DD  ("")
        DST02PP  ("")
        DST03DD  ("")
        DST03PP  ("")
        DST04DD  ("")
        DST04PP  ("")

        (b)  run dep_snow.f90 (from jf): original code: /fis/cgd/home/shields/ccsm4/aerodep
                                         workingdir code: this dir...
                                        /fis/cgd/ccr/shields/permian/ccsm4/atm/presc_aero_files

         (c)  overwrite time and date with 1850 default values, and add source run to global history
              script to do this:                aerodep.nco.csh

ncks --append -v date,time /fis/cgd/ccr/shields/permian/ccsm4/atm/presc_aero_files/default_1850/date_time_1850clim.nc aerosoldep_monthly_12-21_mean_b40.t31x3.pt.4.nc
ncatted -a history,global,a,c,"b40.t31x3.pt.4.cam2.h0* files years 12-21 cshields 110303" aerosoldep_monthly_12-21_mean_b40.t31x3.pt.4.nc


        (d) this seems to work fine w/T31.