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| On this page we track the evolution of the mean OH concentration in GEOS-Chem. This value is an indicator of how "hot" the chemistry is. Please also see the related topic about the [[Methyl chloroform lifetime|methyl chloroform lifetime in GEOS-Chem]]. | | On this page we track the evolution of the mean OH concentration in GEOS-Chem. This value is an indicator of how "hot" the chemistry is. Please also see the related topic about the [[Methyl chloroform lifetime|methyl chloroform lifetime in GEOS-Chem]]. |
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− | == Computation of the mean OH diagnostic ==
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− |
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− | The mean OH diagnostic in GEOS-Chem is computed in <tt>diag_pl_mod.f</tt>.
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− |
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− | Routine <tt>DO_DIAG_OH</tt> sums up the tropospheric air mass and mass-weighted OH mass after each call to the chemistry solver. The summing happens in these lines of code:
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− |
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− | ! Sum air mass term into AIR_MASS array
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− | XAIRMASS = AIRDENS(JLOOP) * VOLUME(JLOOP)
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− | AIR_MASS(I,J,L) = AIR_MASS(I,J,L) + XAIRMASS
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− |
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− | ! Sum OH mass term into OH_MASS array
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− | XOHMASS = CSPEC(JLOOP,IDOH) * XAIRMASS
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− | OH_MASS(I,J,L) = OH_MASS(I,J,L) + XOHMASS
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− |
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− | where the arrays contain the following quantities:
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− |
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− | JLOOP = 1-D array index for SMVGEAR
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− | I,J,L = 3-D array indices
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− | AIRDENS(JLOOP) = air density [molec/cm3]
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− | VOLUME(JLOOP) = grid box volume [cm3]
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− | AIR_MASS(I,J,L) = air mass [molec air]
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− | CSPEC(JLOOP,IDOH) = OH concentration [molec OH/cm3]
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− | OH_MASS(I,J,L) = mass-weighted OH = OH mass * air mass [molec OH/cm3 * molec air]
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− |
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− | After the GEOS-Chem simulation finishes, the mean OH value is printed out in subroutines <tt>PRINT_MEAN_OH</tt>:
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− |
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− | ! Total Mass-weighted OH [molec OH/cm3] * [molec air]
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− | SUM_OHMASS = SUM( OH_MASS )
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− |
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− | ! Atmospheric air mass [molec air]
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− | SUM_MASS = SUM( AIR_MASS )
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− |
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− | ! Divide OH [molec OH/cm3 * molec air] by [molec air] and report as [1e5 molec/cm3]
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− | OHCONC = ( SUM_OHMASS / SUM_MASS ) / 1d5
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− |
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− | ! Write value to log file
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− | WRITE( 6, '(/,a)' ) REPEAT( '=', 79 )
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− | WRITE( 6, * ) 'ND23: Mass-Weighted OH Concentration'
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− | WRITE( 6, * ) 'Mean OH = ', OHCONC, ' [1e5 molec/cm3]'
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− | WRITE( 6, '( a)' ) REPEAT( '=', 79 )
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− |
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− | Typical values vary between 10<sup>5</sup> - 11<sup>5</sup> molec/cm3.
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− |
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− | --[[User:Bmy|Bob Y.]] 15:12, 11 February 2010 (EST)
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| | | |
| == Evolution of mean OH in GEOS-Chem == | | == Evolution of mean OH in GEOS-Chem == |
| | | |
− | === Table of mean OH values === | + | === Plot of mean OH evolution === |
− | | + | |
− | The following table chronicles the evolution of the mean OH value from several different GEOS-Chem simulations. All benchmark simulations were conducted at [http://acmg.seas.harvard.edu/geos/doc/man/appendix_2.html#A2.2 4 x 5 resolution] unless noted otherwise.
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− | | + | |
− | {| border=1 cellspacing=0 cellpadding=5
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− | |- bgcolor="#CCCCCC"
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− | ! Benchmark
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− | ! Met Fields & Year
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− | ! Mean OH<br>[10<sup>5</sup> molec cm<sup>-3</sup>]
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− | ! Change from<br>previous version<br>[10<sup>5</sup> molec cm<sup>-3</sup>]
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− | ! Important updates in this benchmark simulation
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− | ! References
| + | |
− | | + | |
− | |-align="center" valign="top"
| + | |
− | | [[GEOS-Chem v9-01-01#Run1|v9-01-01-Run1]]
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− | | GEOS-5.1.0 2005
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− | | <tt>12.242</tt>
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− | | <tt>+0.377<br>(+3.177%)</tt>
| + | |
− | |<div align="left">
| + | |
− | *[http://seas.harvard.edu/~ltmurray/LNOx.v9-01-01.Release.Notes.pdf Updated lighting parameterization]
| + | |
− | </div>
| + | |
− | |<div align="left">
| + | |
− | *[[GEOS-Chem v9-01-01|v9-01-01 page]]
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− | </div>
| + | |
− | |-align="center" valign="top"
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− | | [[GEOS-Chem v9-01-01#Run0|v9-01-01-Run0]]
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− | | GEOS-5.1.0 2005
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− | | <tt>11.865</tt>
| + | |
− | | <tt>+0.798<br>(+7.2%)</tt>
| + | |
− | |<div align="left">
| + | |
− | *[[Ship_emissions#ICOADS|ICOADS ship emissions]]
| + | |
− | *[[GEOS-Chem_v9-01-01#Important_bug_fixes_for_ship_emissions|Bug fixes for ship emissions]]
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− | *[[EPA/NEI05_North_American_emissions#Biofuel_emissions|Bug fixes for EPA/NEI05 biofuels]]
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− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/deposition/v9-01-01_wetdep.pdf Updates for wet scavenging algorithm]
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− | *[[GEOS-Chem_v9-01-01#Post-release_patches|Several post-release patches to correct various issues]]
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− | </div>
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− | |<div align="left">
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− | *[[GEOS-Chem v9-01-01|v9-01-01 page]]
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− | *[[Wet deposition]] page
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− | *[[Ship emissions]] page
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− | </div>
| + | |
− | |-align="center" valign="top"
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− | | [[GEOS-Chem v8-02-04#Run2|v8-02-04-Run2]]
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− | | GEOS-5.1.0 2005
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− | | <tt>11.067</tt>
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− | | <tt>+0.019<br>(+0.17%)</tt>
| + | |
− | |<div align="left">
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− | *Linoz stratospheric ozone chemistry used instead of SYNOZ scheme
| + | |
− | </div>
| + | |
− | |<div align="left">
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− | *[[Linoz stratospheric ozone chemistry|Linoz wiki page]]
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− | *[[Talk:GEOS-Chem_v8-02-04|Talk:v8-02-04 page]]
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− | </div>
| + | |
− | |-align="center" valign="top"
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− | | [[GEOS-Chem v8-02-04#Run1|v8-02-04-Run1]]
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− | | GEOS-5.1.0 2005
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− | | <tt>11.048</tt>
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− | | <tt>+0.598<br>(+5.72%)</tt>
| + | |
− | |<div align="left">
| + | |
− | *MEGAN hybrid model with MODIS-derived LAI
| + | |
− | </div>
| + | |
− | |<div align="left">
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− | *[[MEGAN biogenic emissions|MEGAN wiki page]]
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− | *[[Talk:GEOS-Chem_v8-02-04|Talk:v8-02-04 page]]
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− | </div>
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− | |-align="center" valign="top"
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− | | [[GEOS-Chem v8-02-04#Run0|v8-02-04-Run0]]
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− | | GEOS-5.1.0 2005
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− | | <tt>10.450</tt>
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− | | <tt>-1.362<br>(-11.53%)</tt>
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− | |<div align="left">
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− | *MEGAN hybrid model with AVHRR-derived LAI
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− | *EPA/NEI2005 emissions
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− | *Non-local PBL mixing scheme
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− | </div>
| + | |
− | |<div align="left">
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− | *[[MEGAN biogenic emissions|MEGAN wiki page]]
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− | *[[EPA/NEI05 North American emissions|NEI2005 wiki page]]
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− | *[[Talk:GEOS-Chem_v8-02-04|Talk:v8-02-04 page]]
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− | *[http://acmg.seas.harvard.edu/publications/jlin5_2009_AE_1.pdf Lin et al 2009]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
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− | | [[GEOS-Chem v8-02-01#Run0|v8-02-01-Run0]]
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− | | GEOS-5.1.0 2005
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− | | <tt>11.812</tt>
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− | | <tt>+0.713<br>(+6.42%)</tt>
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− | |<div align="left">
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− | *Updated chemical mechanism: <tt>globchem.dat</tt>
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− | *Updated photolysis rxn rates: <tt>jv_spec.dat, ratj.d</tt>
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− | | + | |
− | :NOTE: there was [[Chemistry Issues#near-IR photolysis of HNO4|a bug in near IR photolysis of HNO4 and HCHO]] in the <tt>jv_spec.dat</tt> and <tt>ratj.d</tt> files. This was finally resolved in v8-02-04. We recommend all users of v8-02-01, v8-02-02, and v8-02-03 to use these updated [http://acmg.seas.harvard.edu/geos/wiki_docs/chemistry/jv_spec.dat <tt>jv_spec.dat</tt>] and [http://acmg.seas.harvard.edu/geos/wiki_docs/chemistry/ratj.d <tt>ratj.d</tt>] files.
| + | |
− | </div>
| + | |
− | |<div align="left">
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− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/chemistry/chemistry_updates_v5.pdf Chemistry mechanism document]
| + | |
− | *[[Photolysis mechanism|FAST-J wiki page]]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
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− | | [[GEOS-Chem v8-01-04#Run2|v8-01-04-Run2]]
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− | | GEOS-5.1.0 2005
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− | | <tt>11.099</tt>
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− | | <tt>+0.805<br>(+7.82%)
| + | |
− | |<div align="left">
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− | *Updated to the newer GEOS-5.1.0 met data product
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− | *Switched to [http://acmg.seas.harvard.edu/geos/wiki_docs/geos5/GEOS-5_cloud_regridding_equations.pdf Hongyu Liu's regridding algorithm for optical depth]
| + | |
− | </div>
| + | |
− | |<div align="left">
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− | *[[GEOS-5 met field reprocessing|GEOS-5 met field reprocessing wiki page]]
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− | *[[GEOS-5 issues|GEOS-5 issues wiki page]]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
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− | | [[GEOS-Chem v8-01-04#Run1|v8-01-04-Run1]]
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− | | GEOS-5.0.1 2005
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− | | <tt>10.294</tt>
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− | | <tt>-0.395<br>(-3.69%)</tt>
| + | |
− | |<div align="left">
| + | |
− | *Various emissions updates with regional overwrites
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− | *Aaron van Donkelaar et al scale factors for 2005
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− | *Switched from linear to random cloud overlap in FAST-J
| + | |
− | </div>
| + | |
− | |<div align="left">
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− | *[http://wiki.seas.harvard.edu/geos-chem/images/Anth_emiss_gc_v8-01-04.pdf Anthropogenic emissions in v8-01-04]
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− | *[[Photolysis mechanism|FAST-J wiki page]]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
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− | | [[GEOS-Chem v8-01-04#Run0|v8-01-04-Run0]]
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− | | GEOS-5.0.1 2005
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− | | <tt>10.689</tt>
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− | | <tt>-1.351<br>(-11.22%)</tt>
| + | |
− | |<div align="left">
| + | |
− | *[[Biogenic_emissions#Updated_annual_emission_factor_for_Isoprene|New MEGAN annual emission factors for isoprene]]
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− | *New TPCORE
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− | *[[GEOS-5_issues#Quick_fix_for_optical_depth|Quick fix for optical depths]]
| + | |
− | </div>
| + | |
− | |<div align="left">
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− | *[[Biogenic_emissions|Biogenic emissions wiki page]]
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− | *[[GEOS-5_issues|GEOS-5 issues wiki page]]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
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− | | [[GEOS-Chem v8-01-01#Run1|v8-01-01-Run1]]
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− | | GEOS-5.0.1 2005
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− | | <tt>12.040</tt>
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− | | <tt>+0.034<br>(+0.28%)</tt>
| + | |
− | |<div align="left">
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− | *Switched aerosol thermodynamical equilibrium scheme from ISORROPIA I to RPMARES
| + | |
− | </div>
| + | |
− | |<div align="left">
| + | |
− | * [[Aerosol thermodynamical equilibrium|ATE wiki page]]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
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− | | [[GEOS-Chem v8-01-01#Run0|v8-01-01-Run0]]
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− | | GEOS-5.0.1 2005
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− | | <tt>12.006</tt>
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− | | <tt>-0.141<br>(-1.16%)</tt>
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− | |<div align="left">
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− | *First simulation with GEOS-5 met data
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− | </div>
| + | |
− | |<div align="left">
| + | |
− | *[[GEOS-5_issues|GEOS-5 issues wiki page]]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
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− | | [[GEOS-Chem_v7-04-13#Run|v7-04-13-Run]]
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− | | GEOS-4 2005
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− | | <tt>12.147</tt>
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− | | <tt>-0.669<br>(-5.22%)</tt>
| + | |
− | |<div align="left">
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− | *[[Lightning_NOx_emissions#Updated_OTD.2FLIS_local_redistribution_for_GEOS-5|Updated non-near-land OTD/LIS local scaling for lightning]]
| + | |
− | </div>
| + | |
− | |<div align="left">
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− | *[[Lightning NOx emissions|Lightning wiki page]]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
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− | | [[GEOS-Chem_v7-04-12#Run2|v7-04-12-Run2]]
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− | | GEOS-4 2005
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− | | <tt>12.816</tt>
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− | | <tt>+1.053<br>(+8.95%)</tt>
| + | |
− | |<div align="left">
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− | *Original non-near-land OTD/LIS local scaling
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− | </div>
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− | |
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− | <div align="left">
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− | *[[Lightning NOx emissions|Lightning wiki page]]
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− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/Changes_in_CO_O3_in_1yr_benchmarks.pdf Hudman PDF]
| + | |
− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/differences_v7-04-12.pdf v7-04-12 diff list]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
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− | | [[GEOS-Chem_v7-04-12#Run1|v7-04-12-Run1]]
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− | | GEOS-4 2005
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− | | <tt>11.763</tt>
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− | | <tt>-0.68<br>(-5.5%)</tt>
| + | |
− | |<div align="left">
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− | *Ancient lightning scheme
| + | |
− | </div>
| + | |
− | |<div align="left">
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− | *[[Lightning NOx emissions|Lightning wiki page]]
| + | |
− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/Changes_in_CO_O3_in_1yr_benchmarks.pdf Hudman PDF]
| + | |
− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/differences_v7-04-12.pdf v7-04-12 diff list]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
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− | | v7-04-02-MEGAN
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− | | GEOS-4 2001
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− | | <tt>12.44</tt>
| + | |
− | | <tt>-0.11<br>(-0.87%)</tt>
| + | |
− | |<div align="left">
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− | * First benchmark w/ MEGAN biogenic emissions
| + | |
− | </div>
| + | |
− | |<div align="left">
| + | |
− | *[[MEGAN biogenic emissions|MEGAN wiki page]]
| + | |
− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/Changes_in_CO_O3_in_1yr_benchmarks.pdf Hudman PDF]
| + | |
− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/differences_v7-04-02.pdf v7-04-02 diff list]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
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− | | v7-04-02-NOMEGAN
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− | | GEOS-4 2001
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− | | <tt>12.55</tt>
| + | |
− | | <tt>+0.01<br>(+0.08%)</tt>
| + | |
− | |<div align="left">
| + | |
− | * Switched fossil fuel scale year from 1995 to 1998
| + | |
− | * Last benchmark w/ the older GEIA biogenic emissions
| + | |
− | </div>
| + | |
− | |<div align="left">
| + | |
− | *[[Biogenic emissions#GEIA|GEIA wiki page]]
| + | |
− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/Changes_in_CO_O3_in_1yr_benchmarks.pdf Hudman PDF]
| + | |
− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/differences_v7-04-02.pdf v7-04-02 diff list]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
| + | |
− | | v7-04-02-Base
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− | | GEOS-4 2001
| + | |
− | | <tt>12.54</tt>
| + | |
− | | <tt>+0.67<br>(+5.6%)</tt>
| + | |
− | |<div align="left">
| + | |
− | * 43 tracer simulation (no secondary organic aerosols)
| + | |
− | * Last 1-yr benchmark with fossil fuel scale year = 1995
| + | |
− | </div>
| + | |
− | |<div align="left">
| + | |
− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/Changes_in_CO_O3_in_1yr_benchmarks.pdf Hudman PDF]
| + | |
− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/differences_v7-04-02.pdf v7-04-02 diff list]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
| + | |
− | | v7-02-03-Run1
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− | | GEOS-4 2001
| + | |
− | | <tt>11.87</tt>
| + | |
− | | <tt>+1.39<br>(+13.26%)</tt>
| + | |
− | |<div align="left">
| + | |
− | *Secondary organic aerosols (50 tracers)
| + | |
− | *GEOS-4 met fields
| + | |
− | </div>
| + | |
− | |
| + | |
− | <div align="left">
| + | |
− | *[[Secondary_organic_aerosols|SOA wiki page]]
| + | |
− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/Changes_in_CO_O3_in_1yr_benchmarks.pdf Hudman PDF]
| + | |
− | </div>
| + | |
− | |-align="center" valign="top"
| + | |
− | | v7-02-03-Run0
| + | |
− | | GEOS-3 2001
| + | |
− | | <tt>10.48</tt>
| + | |
− | | ---
| + | |
− | |<div align="left">
| + | |
− | *Secondary organic aerosols (50 tracers)
| + | |
− | *GEOS-3 met fields
| + | |
− | </div>
| + | |
− | |<div align="left">
| + | |
− | *[[Secondary_organic_aerosols|SOA wiki page]]
| + | |
− | *[http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/Changes_in_CO_O3_in_1yr_benchmarks.pdf Hudman PDF]
| + | |
− | </div>
| + | |
− | |}
| + | |
− | | + | |
− | --[[User:Bmy|Bob Y.]] 16:32, 8 June 2011 (EDT)
| + | |
− | | + | |
− | === Additional documentation ===
| + | |
− | | + | |
− | ==== GEOS-Chem version 8 ====
| + | |
− | | + | |
− | * [http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/Isoprene_v8-02-04_Run0_vs_Run1.pdf Differences in isoprene between v8-02-04-Run1 and v8-02-04-Run0]
| + | |
− | * [http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/MODIS_LAI_vs_AVHRR_LAI.pdf Differences between MODIS LAI and AVHRR LAI]
| + | |
− | | + | |
− | ==== GEOS-Chem version 7 ====
| + | |
− | | + | |
− | * [mailto:hudman@berkeley.edu Rynda Hudman] investigated the [http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/Changes_in_CO_O3_in_1yr_benchmarks.pdf changes in CO and O3 among benchmark simulations from v7-02-03 thru v7-04-12].
| + | |
− | * [http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/differences_v7-04-02.pdf List of differences in benchmark simulations between v7-02-03 and v7-04-02].
| + | |
− | * [http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/differences_v7-04-02.pdf List of differences in benchmark simulations between v7-04-02 and v7-04-12].
| + | |
− | * [http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/anthro_comparison.mar2001.pdf Changes in anthropogenic NOx and CO from 1-yr benchmarks with versions v7-02-03 and v7-02-04]
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− | * [mailto:jlogan@seas.harvard.edu Jennifer Logan] looked at some of the [http://acmg.seas.harvard.edu/geos/wiki_docs/benchmarks/geos4.vs.geos3.problems.pdf differences between GEOS-3 and GEOS-4 in 1-year benchmark simulations].
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− | --[[User:Bmy|Bob Y.]] 09:32, 23 February 2010 (EST)
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− | == Plot of mean OH evolution in GEOS-Chem ==
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− | Here is a plot of the mean OH concentration from several recent GEOS–Chem 1-year benchmark simulations. The mean OH is an indicator how the chemistry mechanism is performing. Typical values are 10–11 x 10<sup>5</sup> molecules cm<sup>-1</sup>.
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− | [[Image:Mean oh 1yr.png]]
| + | Here is a plot of the mean OH concentration from GEOS-Chem 1-year benchmark simulations. The mean OH is an indicator how the chemistry mechanism is performing. Typical values are 10–12 x 10<sup>5</sup> molecules cm<sup>-1</sup>. |
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− | NOTES:
| + | [[Image:GC_Mean_OH_12.8.0.png|1000px]] |
− | #Runs done with GEOS-3 met are denoted by squares; GEOS-4 met: triangles; GEOS-5 met: circles.
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− | #The large jump in mean OH between [[GEOS-Chem v8-01-04#Run2|v8-01-04-Run2]] and [[GEOS-Chem v8-02-01#Run0|v8-02-01-Run0]] is likely attributed to the photolysis rate updates for ketones and aldehydes. See [http://acmg.seas.harvard.edu/geos/wiki_docs/chemistry/chemistry_updates_v4.pdf this document] about the new photolysis mechanism. However, we are still investigating this.
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− | #The runs done with GEOS-4 met have higher mean OH than the GEOS-3 and GEOS-5 runs because of the missing high cloud optical depth in the GEOS-4 met fields.
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− | #The large jump upward from [[GEOS-Chem v7-04-12#Run1|v7-04-12-Run1]] to [[GEOS-Chem v7-04-12#Run2|v7-04-12-Run2]] is attributed to a major upgrade of the lightning NOx algorithm. v7-04-12 was the first GEOS-Chem version to redistribute flashes regionally according to OTD/LIS statistics.
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− | #[[GEOS-Chem v7-04-13|v7-04-13]] uses the same lightning algorithm as in [[GEOS-Chem v7-04-12#Run2|v7-04-12-Run2]]. However, the lightning flash redistribution according to OTD/LIS statistics was switched from regional to local redistribution.
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− | #v7-04-02-Run0 and v7-04-02-Run1 used GEIA biogenic emissions. v7-04-02-Run2 swiched to MEGAN biogenic emissions.
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− | --[[User:Bmy|Bob Y.]] 15:49, 24 February 2010 (EST) | + | --[[User:Melissa Payer|Melissa Sulprizio]] ([[User talk:Melissa Payer|talk]]) 02:17, 13 August 2023 (UTC) |
On this page we track the evolution of the mean OH concentration in GEOS-Chem. This value is an indicator of how "hot" the chemistry is. Please also see the related topic about the methyl chloroform lifetime in GEOS-Chem.
Here is a plot of the mean OH concentration from GEOS-Chem 1-year benchmark simulations. The mean OH is an indicator how the chemistry mechanism is performing. Typical values are 10–12 x 105 molecules cm-1.