Fix bug in HOBr uptake rate calculation (closes #1746)

[yantosca]

Name and Institution (Required)

Name: Bob Yantosca
Institution: Harvard + GCST

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• Contributing guidelines

Describe the update

This is the companion PR to #1746. In that issue, @viral211 and @beckyalexander have confirmed that the rate law computations for HOBr uptake were being unnecessarily multiplied by scale factors that have already been accounted for in the reaction rate computation.

Line 2046 of KPP/fullchem/fullchem_RateLawFuncs was modified accordingly:

old: k = kIIR1Ltd( C(ind_HOBr), C(ind_SO2), k ) * H%HSO3m
new: k = kIIR1Ltd( C(ind_HOBr), C(ind_SO2), k )  

as was line 2048:

old: k = kIIR1Ltd( C(ind_HOBr), C(ind_SO2), k ) * H%SO3mm
new: k = kIIR1Ltd( C(ind_HOBr), C(ind_SO2), k )

Expected changes

@viral211 wrote:

Fixing this will increase the loss of HOBr (to HBr) and could lower BrOx levels, with a larger effect for simulations that include sea salt aerosol debromination.

Reference(s)

N/A

Related Github Issue(s)

Closes #1746

If possible, this should go into 14.2.0, along with the other chemistry updates. This might help to lower the mean OH concentration, which is currently high.

[yantosca]

All GCHP integration tests passed.

==============================================================================
GCHP: Execution Test Results

GCClassic #12e32c4 Merge PR #307 (branch 'feature/add_submodule_update_issue_template') into dev/14.2.0
GEOS-Chem #b1d03d982 Fix bug in HOBr uptake rate calculation (see issue #1746)
HEMCO     #673ef2a Bug fix: Also allow ".$NC" in a mask file name not to throw an error

Number of execution tests: 5

Submitted as SLURM job: 49441516
==============================================================================
 
Execution tests:
------------------------------------------------------------------------------
gchp_merra2_fullchem................................Execute Simulation....PASS
gchp_merra2_fullchem_benchmark......................Execute Simulation....PASS
gchp_merra2_fullchem_RRTMG..........................Execute Simulation....PASS
gchp_merra2_tagO3...................................Execute Simulation....PASS
gchp_merra2_TransportTracers........................Execute Simulation....PASS
 
Summary of test results:
------------------------------------------------------------------------------
Execution tests passed: 5
Execution tests failed: 0
Execution tests not yet completed: 0

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%  All execution tests passed!  %%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

[yantosca]

All GEOS-Chem Classic integration tests passed, except for TransportTracers. This was fixed in HEMCO PR geoschem/HEMCO#205, which was not merged into this update.

==============================================================================
GEOS-Chem Classic: Execution Test Results

GCClassic #3084f13 GEOS-Chem and HEMCO submodule updates: Write HEMCO restart files to the rundir "Restarts/" subdirectory
GEOS-Chem #b1d03d982 Fix bug in HOBr uptake rate calculation (see issue #1746)
HEMCO     #13abf5e Merge PR #202 (branch 'feature/hemco-restart-folder') into dev/3.7.0

Using 24 OpenMP threads
Number of execution tests: 26

Submitted as SLURM job: 49440719
==============================================================================
 
Execution tests:
------------------------------------------------------------------------------
gc_05x0625_NA_47L_merra2_CH4........................Execute Simulation....PASS
gc_05x0625_NA_47L_merra2_fullchem...................Execute Simulation....PASS
gc_4x5_47L_merra2_fullchem..........................Execute Simulation....PASS
gc_4x5_47L_merra2_fullchem_TOMAS15..................Execute Simulation....PASS
gc_4x5_47L_merra2_fullchem_TOMAS40..................Execute Simulation....PASS
gc_4x5_merra2_aerosol...............................Execute Simulation....PASS
gc_4x5_merra2_carbon................................Execute Simulation....PASS
gc_4x5_merra2_CH4...................................Execute Simulation....PASS
gc_4x5_merra2_CO2...................................Execute Simulation....PASS
gc_4x5_merra2_fullchem..............................Execute Simulation....PASS
gc_4x5_merra2_fullchem_aciduptake...................Execute Simulation....PASS
gc_4x5_merra2_fullchem_APM..........................Execute Simulation....PASS
gc_4x5_merra2_fullchem_benchmark....................Execute Simulation....PASS
gc_4x5_merra2_fullchem_complexSOA...................Execute Simulation....PASS
gc_4x5_merra2_fullchem_complexSOA_SVPOA.............Execute Simulation....PASS
gc_4x5_merra2_fullchem_LuoWd........................Execute Simulation....PASS
gc_4x5_merra2_fullchem_marinePOA....................Execute Simulation....PASS
gc_4x5_merra2_fullchem_RRTMG........................Execute Simulation....PASS
gc_4x5_merra2_Hg....................................Execute Simulation....PASS
gc_4x5_merra2_metals................................Execute Simulation....PASS
gc_4x5_merra2_POPs_BaP..............................Execute Simulation....PASS
gc_4x5_merra2_tagCH4................................Execute Simulation....PASS
gc_4x5_merra2_tagCO.................................Execute Simulation....PASS
gc_4x5_merra2_tagO3.................................Execute Simulation....PASS
gc_4x5_merra2_TransportTracers......................Execute Simulation....FAIL
gc_4x5_merra2_TransportTracers_LuoWd................Execute Simulation....FAIL
 
Summary of test results:
------------------------------------------------------------------------------
Execution tests passed: 24
Execution tests failed: 2
Execution tests not yet completed: 0

[beckyalexander]

Here are the impacts on BrO and O3 for a one-month simulation in January 2019.
SIVBugFix_BrO_O3.pdf
zonal_mean_SIVBugFix_BrO_O3.pdf

[viral211]

Thanks @beckyalexander. It is good to see that the changes in BrO and ozone are in the expected direction. Was sea salt aerosol debromination turned off in your run, or did your include it along with the other halogen updates being added in 14.2?

[beckyalexander]

This was run in version 13.4.1, but with sea salt debromination turned on and all of the halogen updates going into 14.2.