Aerosol-only simulation

From Geos-chem
Revision as of 16:05, 25 August 2022 by Bmy (Talk | contribs)

Jump to: navigation, search

Previous | Next | Guide to GEOS-Chem simulations

  1. Simulations overview
  2. Mechanisms for full-chemistry simulations (e.g. Standard, Tropchem, etc.)
  3. Aerosol-only simulation
  4. CH4 simulation
  5. CO2 simulation
  6. Hg simulation
  7. POPs simulation
  8. Tagged CO simulation
  9. Tagged O3 simulation
  10. TransportTracers simulation


On this page we describe the aerosol-only (a.k.a. offline aerosol) simulation.

Description

The aerosol simulation is an offline simulation for aerosol tracers only. It uses archived monthly mean OH, NO3, O3 and total nitrate concentrations archived from a previous full-chemistry simulation (more on that below), as well as production and loss rates for H2O2. This simulation does not provide "tagged" capabilities, but reduces the suite of tracers from full chemistry.

NOTES:

  1. The aerosol-only simuation is currently functional in GEOS-Chem 13 and GEOS-Chem 14.
  2. There is currently no aerosol-only run directory for GCHP. Interested users are encouraged to make this modification on their own.
  3. The oxidant fields should be updated to use output from a recent GEOS-Chem version.

Assumptions

  1. OH concentrations are archived from the most recent 10-year benchmark simulation.
  2. O3, NO3 and total nitrate (HNO3+NIT) concentrations, as well as production rates and photolysis rates for H2O2 are archived from the most recent 10-year benchmark simulation.

Practicalities

As with all other Offline chemistry simulations, the GEOS-Chem user community shall be responsible for the scientific content and validation of the aerosol-only simulation.

The SOA simulation was updated in GEOS-Chem v9-02o to include a better tracer lumping scheme, as shown in Figure 1 of Pye et al. 2010.

The offline aerosol is simulation type 10. For a full set of aerosol tracers (based on the 100-tracer full-chemistry SOA simulation), the input.geos should look like this:

Type of simulation      : 10
Number of Tracers       : 47
Tracer Entries -------> : TR#  Name   g/mole   Tracer Members; () = emitted
Tracer #1               :  1   DMS     62.00
Tracer #2               :  2   SO2     64.00
Tracer #3               :  3   SO4     96.00
Tracer #4               :  4   SO4s    96.00
Tracer #5               :  5   MSA     96.00
Tracer #6               :  6   NH3     17.00
Tracer #7               :  7   NH4     18.00
Tracer #8               :  8   NIT     62.00
Tracer #9               :  9   NITs    62.00
Tracer #10              : 10   H2O2    34.00
Tracer #11              : 11   BCPI    12.00
Tracer #12              : 12   OCPI    12.00
Tracer #13              : 13   BCPO    12.00
Tracer #14              : 14   OCPO    12.00
Tracer #15              : 15   DST1    29.00
Tracer #16              : 16   DST2    29.00
Tracer #17              : 17   DST3    29.00
Tracer #18              : 18   DST4    29.00
Tracer #19              : 19   SALA    36.00
Tracer #20              : 20   SALC    36.00
Tracer #21              : 21   MTPA   136.23
Tracer #22              : 22   LIMO   136.23
Tracer #23              : 23   MTPO   136.23
Tracer #24              : 24   TSOG1  150.00
Tracer #25              : 25   TSOG2  150.00
Tracer #26              : 26   TSOG3  150.00
Tracer #27              : 27   TSOG0  150.00
Tracer #28              : 28   TSOA1  150.00
Tracer #29              : 29   TSOA2  150.00
Tracer #30              : 30   TSOA3  150.00
Tracer #31              : 31   TSOA0  150.00
Tracer #32              : 32   ISOG1  150.00
Tracer #33              : 33   ISOG2  150.00
Tracer #34              : 34   ISOG3  150.00
Tracer #34              : 35   ISOA1  150.00
Tracer #36              : 36   ISOA2  150.00
Tracer #37              : 37   ISOA3  150.00
Tracer #38              : 38   BENZ    12.00   (6C)
Tracer #39              : 39   TOLU    12.00   (7C)
Tracer #40              : 40   XYLE    12.00   (8C)
Tracer #41              : 41   ASOG1  150.00
Tracer #42              : 42   ASOG2  150.00
Tracer #43              : 43   ASOG3  150.00
Tracer #44              : 44   ASOAN  150.00
Tracer #45              : 45   ASOA1  150.00
Tracer #46              : 46   ASOA2  150.00
Tracer #47              : 47   ASOA3  150.00

This list can be reduced by turning off any aerosol species (eg. SOA, dust, SS, etc). You may also run without the secondary organic aerosols (MTPA, LIMO, MTPO, TSOG0–3, TSOA0–3, ISOG1–3, ISOA1–3, ASOG1–3, ASOA1–3, ASOAN) if you wish (but we recommend that you use them).

--Melissa Sulprizio 12:51, 5 November 2013 (EST)

Previous issues that have now been resolved

Fixed undefined molecular weight of HNO3 in routine SEASALT_CHEM

This fix was included in v11-01j and approved on 03 Dec 2016

In routine SEASALT_CHEM (in GeosCore/sulfate_mod.F), the MW_HNO3 variable was undefined for aerosol-only simulations, which do not use HNO3 as a defined species. This issue was detected by a unit test using the GNU Fortran compiler.

To fix this issue, we have added the following block of code, which defines MW_HNO3 whether or not HNO3 is a defined species:

     ! Get the molecular weight of HNO3 from the species database
     ! if it is defined, otherwise set it manually (bmy, 10/11/16)
     IF ( id_HNO3 > 0 ) THEN
        MW_HNO3 = State_Chm%SpcData(id_HNO3)%Info%emMW_g
     ELSE
        MW_HNO3 = 63.0_fp
     ENDIF

NOTE: This is just a quick fix. Ideally, we will want to declare HNO3 as a non-advected species in the GEOS-Chem species database for these simulationns.

--Bob Yantosca (talk) 16:47, 11 October 2016 (UTC)

Error in ISOROPIAII when sulfate aerosols are turned off

This update was tested in the 1-month benchmark simulation v9-02r and approved on 14 Nov 2013.

Chris Butenhoff wrote:

I set ONLINE SULFATE AEROSOLS = F and removed the sulfate aerosols from the tracer list. However I now get the error "IDTSO4 is undefined" from isoropia11_mod.F (line 207).

For full-chemistry simulations, we only call routine DO_ISOROPIAII if sulfate aerosols are used (i.e. LSULF = T). However, no such check exists when running the offline aerosol simulation. This was probably an oversight and we should add the following fix to routine DO_CHEMISTRY (in GeosCore/chemistry_mod.F):

           !*** AEROSOL THERMODYNAMIC EQUILIBRIUM ***
           IF ( LSULF ) THEN
              IF ( LSSALT ) THEN

#if   !defined( NO_ISORROPIA )
                 ! ISOROPIA takes Na+, Cl- into account
                 CALL DO_ISOROPIAII
    &               ( am_I_Root, Input_Opt, State_Met, State_Chm, RC )
#endif

              ELSE

                 ! RPMARES does not take Na+, Cl- into account
                 ! (skip for crystalline & aqueous offline run)
                 IF ( .not. LCRYST ) THEN
                    CALL DO_RPMARES( am_I_Root, Input_Opt, 
    &                                State_Met, State_Chm, RC )
                 ENDIF
              ENDIF
           ENDIF

--Bob Y. 15:29, 14 November 2013 (EST)

Previous | Next | Guide to GEOS-Chem simulations