GEOS–Chem: A Continually Evolving Model!

Global mean, pressure-weighted tropospheric OH concentration for July in successive GEOS–Chem versions. This is one of the many diagnostics we examine when benchmarking new versions of the GEOS–Chem code. The OH concentration diagnoses how photochemically "hot" the model is. It should be in the range 10 +/-2 x10⁵ molecules cm^-3, as constrained by halocarbon observations.

GEOS–Chem upgrade protocol

We use the Unix Concurrent Versions System (CVS) to archive the GEOS–Chem code.  We update the code incrementally; only a few changes are made from one version to the next.

Each GEOS–Chem release is benchmarked with a standard simulation before it is released to the user community.  The results of the standard simulation are then compared to the results of the standard simulation for the previous GEOS version.  In this way, consistency between successive GEOS–Chem releases can be ensured.  Prof. Daniel Jacob is currently responsible for examining the results of all GEOS–Chem benchmark simulations.

NOTE: Not all GEOS–Chem revisions are released to the user community at large.  Some revisions are necessary for testing purposes.  Also, if many changes to the code are required, it is often expedient to stretch these changes over several revisions, so that each individual revision can be fully tested and benchmarked.

GEOS–Chem development versions

Most recent public release:

• GEOS–Chem v8–01–01
• For more information about v8–01–01, please see the description on the GEOS–Chem public wiki.

Current version in development:

• GEOS–Chem v8–01–02
• For more information about v8–01–02 , please see the description on the GEOS–Chem public wiki.

Previously released GEOS–Chem versions

The following are summaries of the changes contained in each GEOS–Chem release.  Bob Yantosca also maintains more detailed log files which list the changes made to each individual subroutine.  These detailed log files are also included with the output from each benchmark simulation.

GEOS–Chem internal release v8–01–01 (08 May 2008)
Benchmark results checked by djj (08 May 2008)

• Please see the GEOS–Chem public wiki page for v8–01–01

GEOS–Chem internal release v7–04–13 (Nov 2007)
Benchmark results checked by djj (Nov 2007)

• Please see the GEOS–Chem public wiki page for v7–04–13

GEOS–Chem internal release v7–04–12 (Oct 2007)
Benchmark results checked by djj (Oct 2007)

• Please see the GEOS–Chem public wiki page for v7–04–12

GEOS–Chem internal release v7–04–11 (05 Mar 2006)
Benchmark results checked by djj (05 Mar 2006)

• Fixed near-land lightning; now scale 2x25, 4x5 to 6 Tg N/yr (L. Murray, R. Yantosca)
• Now allow ND49, ND50, ND51 to save transects of a single lon or lat (R. Yantosca)
• Add case for T > 293K to routine GET_LWC in "mercury_mod.f" (C. Holmes, R. Yantosca)
• Bug fix: correct indices for embedded chemistry in "transport_mod.f" (P. Le Sager)
• Bug fix: correct typo in SEASALT_CHEM routine in "sulfate_mod.f" (R. Yantosca)
• Now prevent seg fault errors when LBIOMASS=F (R. Yantosca)
• Now fixed minor bug that inverted TROPP1 and TROPP2 (P. Le Sager)
• CMN_SIZE: now define LLTROP_FIX for GCAP.P. Le Sager
• a3_read_mod.f: added SNOW and GETWETTOP fields for GCAP (P. Le Sager)
• main.f: remove duplicate call for unzip in GCAP case (P. Le Sager)
• time_mod.f: fix leap year problem in get_time_ahead for GCAP (P. Le Sager)

GEOS–Chem internal release v7–04–10 (17 Oct 2006)
Benchmark results checked by djj (17 Oct 2006)

• Includes variable tropopause with ND54 diagnostic (P. Le Sager)
• Added GFED2 biomass emissions for additional species: SO2, NH3, BC, OC, CO2 (R. Yantosca)
• Rewrote default biomass emissions routines for clarity (R. Yantosca)
• Updates for GCAP: future emissions, met-field reading, TOMS-O3 (S. Wu)
• Bug fix in planeflight_mod.f: set NCS variable correctly (D. Millet, R. Yantosca)
• Bug fix in SOA_LUMP
• Other minor bug fixes

GEOS–Chem internal release v7–04–09 (12 Sep 2006)
Benchmark results checked by djj (12 Sep 2006)

• Updated David Streets CO emissions (use 2001 for China, use 2000 elsewhere) (R. Yantosca)
• Now reset negative SPHU to a very small positive # (R. Yantosca)
• Remove use of TINY(1d0) to avoid NaN's on SUN platform (R. Yantosca)
• Minor bug fixes and deleted obsolete code

GEOS–Chem internal release v7–04–08 (14 Aug 2006)
Benchmark results checked by djj (14 Aug 2006)

• Now add David Streets' emissions for China & SE Asia
• Removed support for GEOS-1 and GEOS-STRAT met fields
• Removed support for the obsolete Intel IFC and EFC compilers

GEOS–Chem internal release v7–04–07 (04 Aug 2006)
Benchmark results checked by djj (04 Aug 2006)

• Added global EDGAR emissions of NOx, CO, SO2 (Aaron van Donkelaar)
  NOTE: EDGAR emissions are currently turned off in this benchmark simulation.
• Added compiler support for the Sun X4100 platform (R. Yantosca)
• For full-chemistry and aerosol routines that have SO4, NIT, and NH4 as defined tracers, secondary organic gas tracers (SOG) are now condensed onto SO4, NH4, and NIT aerosols. (This takes place within the routine SOA_CHEMISTRY in "carbon_mod.f"). (R. Park)
• Can now regrid emissions data on a 1x1 grid to the GEOS 1 x 1.25 grid. (B. Field, R. Yantosca)
• Bug fix: In routine COMPUTE_F (in "wetscav_mod.f"): now use separate unit conversion factors for H2O2 and NH3. (R. Yantosca)
• Various bug fixes for the CH3I simulation. (P. Palmer, R. Yantosca)
• Bug fix: renamed a common block in "isoropia.h" to avoid variable name confusion (R. Yantosca)

GEOS–Chem internal release v7–04–06 (27 Jun 2006)
Benchmark results checked by djj (27 Jun 2006)

• Now add BRAVO emissions (NOx, CO, SO2) over N. Mexico (F. Boersma)
• Turn off HO2 uptake by aerosols in SMVGEAR mechanism (B. Sauvage)
• Bug fix: GEOS-4 convection now conserves mixing ratio (B. Field)
• Other minor bug fixes & improvements

GEOS–Chem internal release v7–04–05 (06 Jun 2006)
Benchmark results checked by djj (06 Jun 2006)

• Now gets ISOP that has reacted w/ OH from SMVGEAR (D. Henze)
• Incorporated IPCC future emission scale factors (S. Wu)
• Other minor bug fixes

GEOS–Chem internal release v7–04–04 (26 May 2006)
Benchmark results checked by djj (26 May 2006)

• Now updated for SOA production from ISOP (D. Henze)
• Now archive SOA concentrations in [ug/m3] ("diag42_mod.f") (D. Henze, R. Yantosca)
• Other minor bug fixes

GEOS–Chem internal release v7–04–03 (15 May 2006)
Benchmark results checked by djj (15 May 2006)

• Added near-land formulation for lightning (L. Murray, R. Hudman, R. Yantosca)
• Now can use CTH, MFLUX, PRECON params for lightning (L. Murray, R. Hudman, R. Yantosca)
  (NOTE: new lightning is only applied for GEOS-4 for time being)
• Added ND56 diagnostic for lightning flash rates (L. Murray)
• Fixed Feb 28 -> Mar 1 transition for GCAP (i.e. no leap years) (S. Wu)
• Other minor bug fixes

GEOS–Chem internal release v7–04–02 (21 Apr 2006)
Benchmark results checked by djj (21 Apr 2006)

• Implemented GFED2 biomass burning emissions. (P. Kasibhatla)
• Added functionality to "regrid_1x1_mod.f" so that we can now regrid data on the GENERIC 1x1 grid (360 x 180 grid with -180, -90 being the lower left corner EDGE, and with no half-polar boxes). (B. Field)
• Bug fix in routine SEASALT_CHEM in "sulfate_mod.f". Now avoid a segmentation fault for offline aerosol simulations when flag IDTHNO3 is undefined. (B. Alexander, R. Yantosca)
• Bug fix: now block references to ID_Hg2 within nested IF statements. In drydep_mod.f and fvdas_convect_mod.f. This avoids segmentation fault errors for non-Hg simulations. (R. Yantosca)
• Removed obsolete subroutine "chem.f", and incorporated its functionality in to "chemdr.f". (R. Yantosca)
• Removed obsolete, unused variables from a few routines. (R. Yantosca)

GEOS–Chem internal release v7–04–01 (24 Mar 2006)
Benchmark results checked by djj (24 Mar 2006)

• Updates to new Hg simulation (N. Selin, C. Holmes, S. Strode)
• Changed Reynold's # criterion for aerodyn smooth surfaces in drydep (N. Selin)
• Standardized several bug fixes implemented in v7-03-06 patch (R. Yantosca)
• Bug fix: Now call MAKE_RH from "main.f" to avoid problems in drydep (R. Yantosca)
• Removed obsolete code

GEOS–Chem public release v7–03–06 (09 Nov 2005)
Benchmark results checked by djj (09 Nov 2005)

• Added code to read EMEP European anthropogenic emissions (M. Auvray, B. Field)
• Added code modifications for Intel v9 "ifort" compiler (R. Yantosca)
• Bug fixes for AOD output in planeflight & timeseries diagnostics (C. Heald, R. Hudman)
• Turn off scavenging in shallow convection for GCAP simulation (S. Wu)
• Added code to read MEGAN biogenic emissions (M. Fu)
• Added code to read AVHRR LAI for MEGAN (M. Fu)
• Added code to read GEOS-3 "XTRA" met fields (PARDF, PARDR, SNOW) (M.Fu)
• Added code to regrid data from GEOS 1x1 grid to current grid (B. Field)
• Snow depth is now used in GEOS-3 for dust emissions (R. Yantosca)
• Now reference XNUMOL, XNUMOLAIR from "tracer_mod.f" (R. Yantosca)
• Now save column AOD's and AOD's below plane in "planeflight_mod.f" (R. Yantosca)
• Added LINUX_IFORT switch for Intel v8/v9 compiler (R. Yantosca)
• Make sure all module USE commands are USE, ONLY (for ESMF) (R. Yantosca)
• Eliminated obsolete references to include files and modules (R. Yantosca)
• Bug fix for COMPAQ; declare IRMA, IRMB threadprivate in "comode.h" (Q. Liang)
• Contains modifications for GCAP/GISS met fields (S. Wu, R. Yantosca)
• Contains offline CO2 simulation (P. Suntharalingam)
  ### NOTE: CO2 code still needs validation ###
• Improved flagging of land / water / ice grid boxes (R. Yantosca)
• Rescaling of lightning NOx emissions (R. Yantosca)
• Lightning NOx emissions are now turned off in the polar regions (R. Yantosca)
• Removal of some common block variables (R. Yantosca)
• Now uses Nightingale et al 2000b formula for sea-air exchange (S. Wu, R. Yantosca)
• DMS and sea-salt emissions are now turned off in the polar regions (B. Alexander, R. Park)
• Updated code for tagged HCN / CH3CN simulation (Q. Li, Y. Xiao)
• Removed obsolete code such as SLOW-J and CO-OH param simulations (R. Yantosca)
• Removed some variables in common blocks (R. Yantosca)
• GEOS–Chem can now write diaginfo.dat, tracerinfo.dat files for GAMAP (R. Yantosca)
• Now uses ISORROPIA package for aerosol therm. equilibr. (B. Alexander, R. Yantosca)
• Added SO4s, NITs(i.e., SO4 & NIT on sea salt aerosol surface) tracers (B. Alexander)
• Offline aerosol simulation now reads from new oxidant etc. fields (C. Heald, R. Yantosca)
• Now allows for hygroscopic growth of aerosols in dry deposition (R. Park, B. Alexander)
• ND48, ND49, ND50, ND51 timeseries now saves out grid box height (R. Yantosca)
• GEOS-3/GEOS-4 3-D cloud fraction has been added to ND21 diagnostic (R. Yantosca)

Papers based on GEOS–Chem v7–03–06:

• Martin, R.V., B. Sauvage, I. Folkins, C.E. Sioris, C. Boone, P. Bernath, and J.R. Ziemke, Space-based constraints on the production of nitric oxide by lightning, J. Geophys. Res., 112, D09309, doi:10.1029/2006JD007831, 2007. [PDF]

GEOS–Chem public release v7–02–04 (20 Apr 2005)
Benchmark results checked by djj (20 Apr 2005)

• Contains offline mercury simulation and ocean flux of mercury (N.E. Selin, S. Strode)
• Contains EPA/NEI99 emissions for continental USA (R. Park, R. Hudman)
• Centralized PBL mixing routines into "pbl_mix_mod.f" (R.Yantosca)
• GEOS-4 lightning NOx and ISOP are now scaled to the same values as GEOS-3 (R. Yantosca)
• Parallelized dry deposition routine DEPVEL (in "drydep_mod.f") (R. Yantosca)
• Now uses analytic function for sat vap pressure of water (E_ICE) (R. Yantosca)
• ND40 planeflight diag now looks for a new flight track file each day (R. Yantosca)
• Now looks to see if files exist on disk in a platform-independent way (R. Yantosca)
• Bug fix: offline AOD diagnostics give identical results as online AOD's (R. Yantosca)
• Now can use interannual or seasonal biomass for SO2, NH4, BCPO, OCPO
• Corrected platform-specific bugs for on Linux with PGI compiler (R. Yantosca)
Fixed other minor bugs and removed obsolete code (R. Yantosca)

Papers based on GEOS–Chem v7–02–04:

• Auvray M., I. Bey, E. Llull, M.G. Schultz, and S. Rast, A model investigation of the impact of long-range transport on tropospheric ozone chemical tendencies, J. Geophys. Res., submitted, 2006. [PDF]

• Heald, C.L., D.J. Jacob, S. Turquety, R.C. Hudman, R.J. Weber, A.P. Sullivan, R.E. Peltier, E.L. Atlas, J.A. de Gouw, C. Warneke, J.S. Holloway, J.A. Neuman, F.M. Flocke, and J.H. Seinfeld, Concentrations and sources of organic carbon aerosol in the free troposphere over North America, J. Geophys. Res., submitted, 2006. [PDF]

• Henze, D. K., and J. H. Seinfeld, Global secondary organic aerosol formation from isoprene oxidation, Geophys. Res. Let., 33, L09812, doi:1029/2006GL025976, 2006. [PDF]

• Millet, D.B., A.H. Goldstein, R. Holzinger, B. Williams, J.D. Allan, J.-L. Jimenez, D.R. Worsnop, J.M. Roberts, A.B. White, R.C. Hudman, I.T. Bertschi, and A. Stohl, Chemical characteristics of North American surface-layer outflow: Insights from Chebogue Point, J. Geophys. Res, in press, 2006. [PDF]

• Millet, D.B., D.J. Jacob, S. Turquety, R.C. Hudman, S. Wu, A. Fried, J. Walega, B.G. Heikes, D.R. Blake, H.B. Singh, B.E. Anderson, and A.D. Clarke, Formaldehyde distribution over North America: Implications for satellite retrievals of formaldehyde columns and isoprene emission, J. Geophys. Res., in press, 2006. [PDF]

• Park, R. J., D. J. Jacob, N. Kumar, and R. M. Yantosca, Regional visibility statistics in the United States: Natural and transboundary pollution influences, and implications for the Regional Haze Rule, Atmos. Environ., in press, 2006. [PDF]

• Sauvage, B., R. V. Martin, A. van Donkelaar, X. Liu, K. Chance, L. Jaeglé, P. I. Palmer, S. Wu, and T.-M. Fu, Remote sensed and in situ constraints on processes affecting tropical tropospheric ozone, Atm. Chem. Phys., 7, 815-838, 2007. [PDF]

• Sauvage, B., R. V. Martin, A. van Donkelaar, and J.R. Ziemke, Quantification of the factors controlling tropical tropospheric ozone and the South Atlantic maximum, J. Geophys. Res., 112, D11309, doi:10.1029/2006JD008008, 2007. [PDF]

• Turquety, S., J.A. Logan, D.J. Jacob, R.C. Hudman, F.Y. Leung, C.L. Heald, R.M. Yantosca, S. Wu, L.K. Emmons, D.P. Edwards, G.W. Sachse, Inventory of boreal fire emissions for North America in 2004: the importance of peat burning and pyro-convective injection, J. Geophys. Res, submitted, 2006. [PDF]

• van Donkelaar, A., R. V. Martin, R. J. Park, C. L. Heald, T.-M. Fu, H. Liao, and A. Guenther, Model evidence for a significant source of secondary organic aerosol from isoprene, Atmos. Environ., 41, 1267-1274, 2007. [PDF]

• Wang, Y.H., Y. Choi, T. Zeng, B. Ridley, N. Blake, D. Blake, and F. Flocke, Late spring increase of trans-Pacific pollution transport in the upper troposphere, Geophys. Res. Lett, submitted, 2005. [PDF]

• Wu, S, L.J. Mickley, D.J. Jacob, J.A. Logan, and R.M. Yantosca, Why are there large differences between models in global budgets of tropospheric ozone?, J. Geophys. Res, submitted, 2006. [PDF]

• Zhang, L., D. J. Jacob, K. W. Bowman, J. A. Logan, S. Turquety, Q. Li, R. Beer, H. M. Worden, J. R. Worden, C. P. Rinsland, S. S. Kulawik, M. C. Lampel, M. W. Shephard, B. M. Fisher, and A. Eldering, Continental outflow of ozone pollution as determined by O3-CO correlations from the TES satellite instrument, Geophys. Res. Lett, submitted, 2006. [PDF]

GEOS–Chem public release v7–01–02 (20 Oct 2004)
Benchmark results checked by djj (20 Oct 2004)

• Brand new GEOS–Chem user interface with new "input.geos" file (R. Yantosca)
• Updated ND48, ND49, ND50, ND51, ND52 timeseries diagnostics (R. Yantosca)
• Updated mean OH diagnostic code (R. Yantosca)
• Updated chemical production & loss diagnostic code (R. Yantosca)
• Can now compute aerosol optical depths in offline aerosol simulations (C. Heald, R. Yantosca)
• Aerosol optical depths are now scaled to 400 nm (R. Yantosca)
• Sea salt size bins redefined to 0.1–0.5 and 0.5–10 microns. (B. Alexander, C. Heald)
• Wet deposition and cloud convection code now parallelizes on Altix platform (R. Yantosca)

Papers based on GEOS–Chem v7–01–02:

• Folkins, I., P. Bernath, C. Boone, A. Eldering, G. Lesins, R.V. Martin, B.-M. Sinnhuber, and K. Walker, Testing convective parameterizations with tropical measurements of HNO3, CO, H2O, and O3: implications for the water vapor budget, J. Geophys. Res., 111, D23304, doi:10.1029/2006JD007325. [PDF]

• Heald, C.L., D.J. Jacob, R.J. Park, B. Alexander, T.D. Fairlie, D.A. Chu, R.M. Yantosca, Transpacific transport of Asian anthropogenic aerosols and its impact on surface air quality in the United States, J. Geophys. Res., 111, D14310, doi:10.1029/2005JD006847, 2006. [PDF]

• Hu, R.-M., R.V. Martin, and T.D. Fairlie, Global retrieval of columnar aerosol single scattering albedo from space-based observations, J. Geophys. Res., 112, D02204, doi: 10.1029/2005JD006832, 2007. [PDF]

• Martin, R.V., C.E. Sioris, K. Chance, T.B. Ryerson, T.H. Bertram, P.J. Wooldridge, R.C. Cohen, J.A. Neuman, A. Swanson, and F.M. Flocke, Evaluation of space-based constraints on global nitrogen oxide emissions with regional aircraft measurements over and downwind of eastern North America, J. Geophys. Res., 111, D15308, doi:10.1029/2005JD006680, 2006. [PDF]

GEOS–Chem public release v6–02–05 (01 Jun 2004)
Benchmark results checked by djj (01 Jun 2004)

• Now can read GEOS-4 a_llk_04 met fields (R. Yantosca)
• Added hydrophobic & hydrophilic BC and OC as tracers (R. Park)
• Added routines for dust emissions & chemistry (D. Fairlie)
• Now can read GEOS-3 extra GWET met field files (D. Fairlie)
• Added dust tracers in 4 different size-bins (D. Fairlie)
• Parallelized extra sections of code which execute only on single-processor (R. Yantosca)
• Added accumulation-mode and coarse-mode sea salt tracers (B. Alexander)
• Added emissions of SO2 from ship exhaust (B. Alexander)
  

Papers based on GEOS–Chem v6–02–05:

• Hudman, R.C., D.J. Jacob, O.C. Cooper, M.J. Evans, C. L. Heald, R.J. Park, F. Fehsenfeld, F. Flocke, J. Holloway, G. Hubler, K. Kita, M. Koike, Y. Kondo, A. Neuman, J. Nowak, S. Oltmans, D. Parrish, and J.M. Roberts, T. Ryerson, Ozone production in transpacific Asian pollution plumes and implications for ozone air quality in California, J. Geophys. Res., 109, D23S10,10.1029/2004JD004974, 2004 .[PDF]

• Park, R.J., D.J. Jacob, P.I. Palmer, A.D. Clarke, R.J. Weber, M.A. Zondlo, F.L. Eisele, A.R. Bandy, D.C. Thornton, G.W. Sachse, and T.C. Bond, Export efficiency of black carbon aerosol in continental outflow: global implications, J. Geophys. Res., 110, D11205, doi:10.1029/2004JD005432, 2005. [PDF]

GEOS–Chem public release v6–01–05 (09 Apr 2004)
Benchmark results checked by djj (09 Apr 2004)

• Updated deep & shallow convection code for GEOS-4 met fields (S. Wu)
• Bug fix in routine NFCLDMX to allow 2x25 runs on Altix (R. Yantosca)
• Updated code to read GEOS-4 met fields (R. Yantosca)
• Bug fix in sulfate emissions code: convert GEOS-4 PBL from [m] to [hPa] (R. Yantosca)
• GEOS-4 Lightning emissions now are scaled to 6 Tg N/yr (R. Yantosca)
• Bug fix: Acetone emissions are now the same on both 2x25 and 4x5 grids (R. Yantosca)
• Fixed bug in 222Rn emissions (S. Wu)
• Updated comments, cosmetic changes
  

Papers based on GEOS–Chem v6–01–05:

• Liu, X., K. Chance, C.E. Sioris, T.P. Kurosu, R,J.D. Spurr, R.V. Martin, T.M. Fu, J.A. Logan, D.J. Jacob, P.I. Palmer, M.J. Newchurch, I.A. Megretskaia, and R. Chatfield, First directly-retrieved global distribution of tropospheric column ozone from GOME: comparison with the GEOS-Chem model, J. Geophys. Res., 111, D02308, 2006. [PDF]

• Palmer, P.I., P. Suntharalingham, D.B. A. Jones, D.J. Jacob, D.G. Streets, Q. Fu, S. Vay, G.W. Sachse, Exploiting observed CO:CO2 correlations to improve inverse analyses of carbon fluxes, , J. Geophys. Res., 111, D12318, doi:10.1029/2005JD006697, 2006. [PDF]

• Palmer, P. I., D. S. Abbot, T-Z. Fu, D. J. Jacob, K. Chance, T. P. Kuruso, A. Guenther, C. Wiedinmyer, J. C. Stanton, M. J. Pilling, S. N. Pressley, B. Lamb, and A. L. Sumner, Quantifying the seasonal and interannual variability of North American isoprene emissions using satellite observations of formaldehyde column, J. Geophys. Res., 111, D12315, doi:10.1029/2005JD006689, 2006. [PDF]

GEOS–Chem public release v5–07–08 (10 Oct 2003)
Benchmark results checked by djj, mje (10 Oct 2003)

• Allow SMVGEAR II background CH4 to vary as a function of latitude and year (M. Evans)
• Implements a more computationally efficient ND65 prod/loss diagnostic (20-30% faster!) (R. Yantosca)
• Scale existing FAST-J O3 climatology with to monthly-mean values from EP-TOMS data (M. Evans)
• Update SMVGEAR II reaction rates (in "globchem.dat") to JPL 2000 (M. Evans)
• Modify dry deposition algorithm for better treatment of HNO3 with GEOS-3 meteorology (R. Park)
• Update N205 hydrolysis reaction probability("gamma") (M. Evans)
• Increased stratospheric O3 flux to 500 Tg/yr (M. Evans)

Papers based on GEOS–Chem v5–07–08:

• Evans, M.J., and D.J Jacob, Impact of new laboratory studies of N2O5 hydrolysis on global model budgets of tropospheric nitrogen oxides, ozone and OH, Geophys. Res. Lett, L09813, 2005. [PDF]

• Fiore, A.M., L.W. Horowitz, D.W. Purves, H. Levy II, M.J. Evans, Y.X. Wang, Q. Li, and R.M. Yantosca, Evaluating the contribution of changes in isoprene emissions to surface ozone trends over the eastern United States, J. Geophys. Res, 110, D12303, doi:10.1029/2004JD005485, 2005. [PDF]

• Suntharalingam, P., J.T. Randerson, N. Krakauer, D.J. Jacob and J.A. Logan, The Influence of Reduced Carbon Emissions and Oxidation on the Distribution of Atmospheric CO2: Implications for Inversion Analyses, Glob. Biogeochem. Cycles, 19, GB4003, doi:10,1029/2005GB002466, 2005. [PDF]

• Wang, Y.X., M.B. McElroy, T. Wang, P.I. Palmer, Asian emissions of CO and NOx: constraints from aircraft and Chinese station data, J. Geophys. Res., 109, D24304, 2004. [PDF]

GEOS–Chem public release v5–06 (01 Jul 2003)

• Ability to read GEOS-4/fvDAS met fields from disk
• Now supports compilation on IBM/AIX platform
• Includes untested GEOS-4/fvDAS convection routines

GEOS–Chem public release v5–05–03 (11 Jun 2003)
Benchmark results checked by djj (11 Jun 2003)

• SMVGEAR II chemistry solver package replaces old SMVGEAR I code
• Added new version of S-J Lin TPCORE transport code for GEOS-4/fvDAS (contains MPI code)
• Implemented LLNL pressure fixer (cf Phil Cameron-Smith) into the new GEOS-4/fvDAS TPCORE to ensure that mass is conserved globally. This makes the met field pressure consistent with the met field winds.
• Updated ND65 chemical family prod-loss diagnostic for SMVGEAR II
• Minor bug fixes and updates to documentation

Papers based on GEOS–Chem v5–05–03:

• Liu, H., J.H. Crawford, R.B. Pierce, P. Norris, S.E. Platnick, G. Chen, J.A. Logan, R.M. Yantosca, M.J. Evans, C. Kittaka, Y. Feng, and X. Tie, Radiative effect of clouds on tropospheric chemistry in a global three-dimensional chemical transport model, J. Geophys. Res, in press, 2006. [Abstract] [PDF]

• Jaeglé, L., L. Steinberger, R. V. Martin, and K. Chance, Global partitioning of NOx sources using satellite observations: Relative roles of fossil fuel combustion, biomass burning and soil emissions, Faraday Discussions, 130, 407-423, doi: 10.1039/b502128f, 2005. [PDF]

• Sinha, P., L. Jaeglé, P.V. Hobbs, and Q. Liang, Transport of biomass burning emissions from southern Africa, J. Geophys. Res., 109, D20204, doi:10.1029/2004JD005044, 2004. [PDF]

• Wang, Y.H and T. Zeng, On tracer correlations in the troposphere: The case of ethane and propane, J. Geophys. Res., 109, D24306, doi:10.1029/2004JD005023, 2004. [PDF]

GEOS–Chem public release v5–04 (11 Apr 2003)
Benchmark results checked by djj (09 Apr 2003)

• Implements nested-grid simulation capability.
• Removed much historical baggage from various header files and routines.
• Lat, lon, and surface areas are now computed by routines in F90 module grid_mod.f.
• All date, time, local time, and timestep values are now computed by routines in F90 module time_mod.f
• Local time is now computed consistently everywhere within GEOS–Chem as Local Time = Longitude + (GMT / 15).
• We no longer add ½ the dynamic timestep to the Longitude, this was pure historical baggage from the old Harvard/GISS II model.
• Added F90 module tpcore_window_mod.f for 1x1 nested grid transport.
• Added F90 module tpcore_bc_mod.f to save and read boundary conditions for nested grid transport.
• Added F90 modules emissions_mod.f and chemistry_mod.f, which select the proper emissions and chemistry routines for the various types of GEOS–Chem simulations.
• Bug fix in FAST-J photolysis code.We now use the current day of year to compute the variance of the solar constant. Previously, we had used the cumulative number of days since 1985. This problem was just pure historical baggage. This fix may cause some minor changes to J-values and OH (which are evident as vertical streaks in the ratio plots). However, this bug fix has a minor impact on the chemistry.
• Updated the "look and feel" of the GEOS–Chem standard output. This will make GEOS–Chem log files easier to read.
• Other various minor improvements, updated comments, and cosmetic changes.

Papers based on GEOS–Chem v5–04:

• Alexander, B., J. Savarino, C.C.W. Lee, R.J. Park, D.J. Jacob, M.H. Thiemens, Q.B. Li, R.M. Yantosca, Sulfate formation in sea-salt aerosols: Constraints from oxygen isotopes, J. Geophys. Res., 110, D10307, 2005. [PDF]

• Duncan, B.N., and I. Bey, A modeling study of export pathways of pollution from Europe: Seasonal and interannual variations., J. Geophys. Res, 109, doi:10.1029/2003JD004079, 2004. [PDF]

• Li, Q.B., J.H. Jiang, D.L. Wu, W.G. Read, N.J. Livesey, J.W. Waters, Y.S. Zhang, B. Wang, M.J. Filipiak, C.P. Davis, S. Turquety, S.L. Wu, R.J. Park, R.M. Yantosca, and D.J. Jacob, Convective outflow of South Asian pollution: a global CTM simulation compared with EOS MLS observations, Geophys. Res. Lett., 32, L14826, 2005. [PDF]

GEOS–Chem public release v5–03–01 (03 Feb 2003)
Benchmark simulation results checked by djj (09 Apr 2003)

• DMS and SO2 chemistry is now done via SMVGEAR for coupled chemistry/sulfate runs
• Natural source NH3 is now emitted and archived (sulfate_mod.f)
• Added C-preprocessor switches and error checking for Sun/Sparc platform (define.h, error_mod.f) Renamed C-preprocessor switch from DEC_COMPAQ to COMPAQ for Alpha platform (define.h)
• Now use external ACCESS command for directory checking on Alpha platform (setup.f)
• Now convert scavenged SO2 on raindrops to SO4 via aqueous chemistry (wetscav_mod.f)
• Minor bug fixes in FORMAT statements: replace missing commas

GEOS–Chem public release v5–03 (03 Feb 2003)
Benchmark simulation results checked by djj (03 Feb 2003)

• Added 7 new sulfate and nitrogen tracers (DMS, SO2, SO4, MSA, NH3, NH4, NIT)
• Added coupled full-chemistry/sulfate aerosol simulation (sulfate_mod.f)
• Added offline sulfate simulation capability (sulfate_mod.f)
• Added new module for tracer ID flags (tracerid_mod.f)
• Packaged dry deposition code in to an F90 module.
• Also updated dry deposition routines to handle the new sulfate tracers. (drydep_mod.f)
• Updated wet deposition code for the new sulfate tracers.
• Packaged additional standalone routines into a F90 module. (wetscav_mod.f)
• Added aerosol thermodynamical phase equilibrium code from Binkowski et al. (rpmares_mod.f)
• Cleaned up many obsolete routines.
• Improved documentation and removed historical baggage.

Papers based on GEOS–Chem v5–03:

• Bertschi, I.T., D.A. Jaffe, L. Jaeglé, H.U. Price, and J.B. Dennison, PHOBEA/ITCT 2002 Airborne observations of trans-Pacific transport of ozone, CO, VOCs, and aerosols to the Northeast Pacific: Impacts of Asian anthropogenic and Siberian boreal fire emissions, J. Geophys. Res., 109(D23), doi:10.1029/2003JD004200, 2004. [PDF]

• Jaffe, D., I. Bertschi, L. Jaeglé, P. Novelli, J. Reid, H. Tanimoto, R. Vingarzan, and D. Westphal, Long-range transport of Siberian biomass burning emissions: Impact on surface ozone in western North America, Geophys. Res. Lett., 31, L16106, doi:10.1029/2004GL020093, 2004. [PDF]

• Li, Q.B., J.H. Jiang, D.L. Wu, W.G. Read, N.J. Livesey, J.W. Waters, Y.S. Zhang, B. Wang, M.J. Filipiak, C.P. Davis, S. Turquety, S.L. Wu, R.J. Park, R.M. Yantosca, and D.J. Jacob, Convective outflow of South Asian pollution: a global CTM simulation compared with EOS MLS observations, Geophys. Res. Lett., 32, L14826, 2005.

• Liang, Q., L. Jaegle, D. A. Jaffe, P. Weiss, A. McClintick, and J. Snow, Long-range Transport to the Northeast Pacific: Seasonal variations and transport pathways of carbon monoxide, J. Geophys. Res., 109(D23), D23S07, doi:10.1029/2003JD004402, 2004. [PDF]

GEOS–Chem public release v5–02 (01 Oct 2002)
Benchmark simulation results checked by djj (01 Oct 2002)

• Added pressure_mod.f which contains routines for computing the grid box edge and center pressures for both pure-sigma grids and sigma-pressure grids.  This is necessary for the transition to fvDAS. 
• Incorporated the floating surface pressure scheme of Phil Cameron-Smith.  We now let TPCORE adjust the surface pressure instead of interpolating it from the met fields. 
• GEOS-3 isoprene and acetone from ocean sources have now been scaled to better match observed values.  Since GEOS-3 surface temperatures are slightly higher than in GEOS-1 and GEOS-STRAT, this causes more biogenic isoprene and acetone to be produced. 
• Removed many obsolete variables from common blocks.  This facilitates the transition to fvDAS meteorology. 

Papers based on GEOS–Chem v5–02:

• Wang, J.S., J. A. Logan, M. B. McElroy, B. N. Duncan, I. A. Megretskaia, and R. M. Yantosca, A 3-D model analysis of the slowdown and interannual variability in the methane growth rate from 1988 to 1997, Global Biogeochem. Cycles, 18, GB3011, doi:10.1029/2003GB002180, 2004. [Abstract] [PDF]

• Wang, Y.X., M.B. McElroy, D.J. Jacob, R.M. Yantosca, A nested grid formation for chemical transport over Asia: applications to CO, J. Geophys. Res., 109, D22307, doi:10.1029/2004jd005237, 2004. [PDF]

• Yoshida, Y., Y.H. Wang, T. Zeng, and R.M. Yantosca, A Three-Dimensional Global Model Study of Atmospheric Methyl Chloride Budget and Distributions, J. Geophys. Res., 109, D24309, doi:10.1029/2004JD004951, 2004. [PDF]

GEOS–Chem public release v5–01 (10 Sep 2002)
Benchmark simulation results checked by djj (10 Sep 2002)

• Added planeflight_mod.f, which incorporates Mat Evans' flight track following diagnostic.  Instead of saving out 3-D fields, one can now request diagnostic output to be printed out only at those locations corresponding to aircraft positions. 
• Added file_mod.f to hold all logical file units in one location. 
• Added restart_mod.f, which contains updated code for reading in GEOS–Chem restart files. Unit conversion to kg is done here, thus eliminating the need for calling old obsolete subroutine trace0.f. 
• Updated RnPbBe_mod.f with the most recent code from Hongyu Liu. 
• Included widespread coding changes to facilitate the transition to the fvDAS meteorology. 
• Elimination of old, obsolete code. 

GEOS–Chem v4–34 (17 Jun 2002)
Benchmark simulation results checked by djj (17 Jun 2002)

• Minor bug fixes in acetone_mod.f.  We now use equations of the form exp(-x) instead of the first order approximation 1-x when computing the ocean sink of acetone.  This avoids negative concentrations. 
• Minor bug fix for ND51 diagnostic. Avoid writing data at local times before the start of the run to the output file. 

GEOS–Chem v4–33 (17 Jun 2002)
Benchmark simulation results checked by djj (16 Jun 2002)

• Bug fixes in biomass_mod.f, biofuel_mod.f: convert to molec/cm3/s on each emission timestep.  This needs to be done since the box volumes and box heights change on every timestep with the surface pressures.  The result of these fixes is that the amount of tracer emitted into the model will be consistent with the amount of tracer reported by the diagnostics. 
• Bug fix in biofuel_mod.f: Now read in the correct amount of biofuel emissions for ACET, C3H8, and C2H6.  Due to an error in processing, these numbers were read in as Tg ACET, Tg C3H8, Tg C2H6, but were treated like Tg C.  The correct totals are now 0.3 Tg C from ACET, 2.0 Tg C from C2H6, and 0.9 Tg C from C3H8. 
• Bug fix in error_mod.f: now include NaN and Infinity checking for the Linux platform.  This should have been introduced a while back, but had been omitted. 
• Now declare internal routines in modules PRIVATE so that they will not be seen outside of the module in which they are located.  This will help eliminate naming conflicts.
• Other minor bug fixes, cosmetic changes, and comment updates. 

Papers based on GEOS–Chem v4–33:

• Fiore, A.M., D.J. Jacob, H. Liu, R.M. Yantosca, T.D. Fairlie, and Q. Li, Variability in surface ozone background over the United States: Implications for air quality policy, J. Geophys. Res., 108, 4787, doi:10.1029/2003JD003855, 2003. [Abstract] [PDF]

• Heald, C.L., D.J. Jacob, A.M. Fiore, L. Emmons, J.C. Gille, G.W. Sachse, E.V. Browell, M.A. Avery, S.A. Vay, J.H. Crawford, D.J. Westberg, D.R.Blake, H.B.Singh, S.T. Sandholm, R.W. Talbot, and H.E. Fuelberg, Asian outflow and transpacific transport of carbon monoxide and ozone pollution: An integrated satellite, aircraft and model perspective, J. Geophys. Res., 108(D24), 4804, doi:10.1029/2003JD003507, 2003. [Abstract] [PDF]

• Heald, C.L., D.J. Jacob, D.B.A. Jones, P.I. Palmer, J.A. Logan, D.G. Streets, G.W. Sachse, J.C. Gille, R.N. Hoffman, and T. Nehrkorn, Comparative inverse analysis of satellite (MOPITT) and aircraft (TRACE-P) observations to estimate Asian sources of carbon monoxide, J. Geophys. Res., 109, D23306, doi:10.1029/2004JD005185, 2004. [PDF]

• Li, Q, D.J. Jacob, R.M. Yantosca, C.L. Heald, H.B. Singh, M. Koike, Y. Zhao, G.W. Sachse, D.G. Streets, A Global 3-D Model Evaluation of the Atmospheric Budgets of HCN and CH₃CN: Constraints From Aircraft and Ground Measurements, J. Geophys. Res., 108, 8827, doi:10.1029/2002JD003075, 2003. [PDF]

• Li, Q., D.J. Jacob, J.W. Munger, R.M. Yantosca, and D.D. Parrish, Export of NO_y from the North American Boundary Layer: Reconciling Aircraft Observations and Global Model Budgets, J. Geophys. Res., 109(D2), D02109, doi:10.1029/2003JD003912, 2004. [Abstract] [PDF]

• Suntharalingam, P., D. J. Jacob, P. I. Palmer, J. A. Logan, R. M. Yantosca, Y. Xiao, M. J. Evans, D. Streets, S. A. Vay and G. Sachse, J. Geophys. Res., 109, D18S18, 2004. [PDF]

GEOS–Chem v4–32 (24 Apr 2002)
Benchmark simulation results checked by djj (24 Apr 2002)

• Updated O₃ + hv --> O¹D photolysis cross sections (located in FAST-J input file jv_spec.dat) with new data from JPL 2000. 
• Added a few minor fixes (submitted by Lyatt Jaegle) to facilitate compilation and execution on the Alpha platform. 

Papers based on GEOS–Chem v4–33:

• Jacob, D.J., B.D. Field, Q. Li, D.R. Blake, J. de Gouw, C. Warneke, A. Hansel, A. Wisthaler, and H.B. Singh, Global budget of methanol: constraints from atmospheric observations, J. Geophys. Res., 110, D08303, 2005. [PDF]

GEOS–Chem v4–31(16 Apr 2002)
Benchmark simulation results checked by djj (16 Apr 2002)

• Bug fix: air mass quantities are now computed correctly before and after the call to TPCORE.  If you start with a constant mixing ratio field, you will get back a constant mixing ratio field exactly, without any signs of numerical noise. 
• Eliminated the need for most symbolic links; routines now can read directly from the /data/ctm/GEOS_2x2.5 and /data/ctm/GEOS_4x5 data directory structure. 
• Cleaned up some old code, added comment headers, and updated comments.

GEOS–Chem v4–30 (26 Mar 2002)
Benchmark simulation results checked by djj (27 Mar 2002)

• Added optical depths from 5 different aerosol types (sulfate, black carbon, organic carbon, sea salt/accumulation, and sea salt/coarse) into FAST-J photolysis routines. 
• Aerosol concentration fields were supplied by Mian Chin (from GSFC).  Further details are in a paper in preparation by Randall Martin.
• Heterogeneous chemistry is now computed on 5 types of aerosol (sulfate, black carbon, organic carbon, sea salt/accumulation, and sea salt/coarse).  Aerosol concentration fields were supplied by Mian Chin (from GSFC).  Further details are in a paper in preparation by Randall Martin.
• Now also save out HO2 and NO2 as part of the ND43 chemical production diagnostic. 
• Comment out the code in emissdr.f where we generate CO from methanol, in order to avoid double-counting.  We currently impose an initial distribution of methanol within the routine initgas.f. 
• Added support for compilation and error trapping on Linux boxes using the Portland Group's (PGI) compiler. 
• Also added Makefile.linux, the makefile for the Linux platform, and linux_err.c, a file containing C-language routines necessary for NaN and infinity error checking. 
• Removed obsolete, commented-out code from several routines.
• Various other minor bug fixes and cosmetic changes.

GEOS–Chem v4–29 (25 Feb 2002)
Benchmark simulation results checked by djj (26 Mar 2002)

• initgas.f, chemdr.f: For SMVGEAR, the initial background concentration of methanol (MOH) is now a function of location on the globe:
  • 2.0 ppbv MOH in the continental boundary layer
  • 0.9 ppbv MOH in the marine boundary layer
  • 0.6 ppbv MOH in the free troposphere
• The above values are taken from recent work by Brian Heikes et al (2002), and represent the best estimate of MOH concentrations based on various observations.
• aircraft_nox_mod.f: Bundled former standalone routines airemiss.f, readair.f, and header file aircraft.h into this F90 module for easier bookkeeping.
• tagged_co_mod.f: Bug fix: now make sure to multiply the CO_OH variable by GCO, in order to convert to an actual amount of CO lost.  This will prevent CO from piling up in the stratosphere.

GEOS–Chem v4–28 (06 Feb 2002)
Benchmark simulation results checked by djj (13 Feb 2002)

• Updates for the wet scavenging algorithm: (Hongyu Liu)
  • compute_f.f: now avoid subscript-out-of-range errors for HNO3, Pb210, and Be7 "aerosol" scavenging
  • rainout.f: do not suppress scavenging of HNO3, Pb210, Be7 below -15 C
• Packaged existing CH3I emissions and chemistry routines into F90 module ch3i_mod.f for easier bookkeeping (Bob Yantosca)
• Introduced new F90 module c2h6_mod.f, which contains routines for C2H6 emissions and chemistry (Yaping Xiao)
• Now can read fossil fuel scale factor files for 1997 and 1998 (Andrew Fusco) Various minor changes (Bob Yantosca):
• dao_mod.f, readair.f, readlai.f, read_tropopause.f now read input files from subdirectories of /data/ctm/GEOS_2x2.5 or /data/ctm/GEOS_4x5 without the need for symbolic links
• CMN_GCTM: Radius of earth changed to 6.375d6 to be consistent w/ GAMAP

GEOS–Chem v4–27 (22 Jan 2002)
Benchmark simulation results checked by djj (13 Feb 2002)

• The large change in the methylchloroform lifetime between GEOS–Chem versions 4.26 and 4.27 occurs because OH has decreased due to updates to the chemical mechanism.  The most important change is the faster rate constant for O(1D) + N2 (which slows down OH production) as recommended by Ravishankara et al., 2002.  Information on the additional updates to the chemical mechanism can be found HERE. Updates for the chemistry mechanism (Arlene Fiore):
• calcrate.f: HARDWIRE addition of 1e-5 s-1 photolysis rate to HNO4 -> HO2+NO2 to account for HNO4 photolysis in near-IR (see Roehl et al 2002).
• chemset.f: Now look for "B" flag in input file chem.dat to denote new HNO4 photolysis reaction, assign to NKHNO4 variable
• comode.h: Add NKHNO4 variable into /Chem4/ common block for updated chemistry mechanism
• fyrno3.f: Return to using a yield of 12% for ISN2 (Isoprene Nitrate) instead of using a yield of 4%
• chem.dat: revised reaction rates (see file header)
• Various bug fixes (Bob Yantosca):
• diag49.f, diag50.f, diag51_mod.f, read49.f: Now save data to disk properly, even for simulations that use a grid of less than global size.  (Yuxuan Wang)
• dao_mod.f Routines is_land and is_water now discern land/water boxes correctly for GEOS-3 for the year 1998 and for years 2000-onward. 
• global_oh_mod.f, global_nox_mod.f now make sure to regrid from GEOS-3 48L grid -> 30L grid properly.  (Bob Yantosca)
• initialize.f: take steps to avoid using an array before it has been allocated.  (Bob Yantosca)
• tagged_co_mod.f: Eliminated duplicate variable definition.  (Bob Yantosca)
• rdust.f: For GEOS-STRAT and Dec 1995, read mineral dust data from Dec 1996.  There is no mineral dust data from 1995, we must use 1996 as a proxy.  (Bob Yantosca)
• ndxx_setup.f Avoid allocation errors.  (Bob Yantosca)
• depvel.f: Add I10 to the format string #1001 (Bob Yantosca)
• compute_f.f: For aerosol scavenging in the Rn-Pb-Be simulation, rewrote code so as to avoid a subscript-out-of-bounds condition.
• Introduced new F90 module uvalbedo_mod.f.  (Bob Yantosca)
• Renamed paftop.f to debug_msg.f for clarity. 
• Removed obsolete routine paftop2.f.  (Bob Yantosca)
• Removed obsolete code and also updated comments in a few routines. (Bob Yantosca)

GEOS–Chem v4–26 (06 Dec 2001)
Benchmark simulation results checked by djj (22 Dec 2001)

• Updated biomass burning emissions from 10/2001 are now the default (Randall Martin)

Papers based on GEOS–Chem v4–26:

• Abbot, D. S., P. I. Palmer, R. V. Martin, K. V. Chance, D. J. Jacob, and A. Guenther, Seasonal and interannual variability of isoprene emissions as determined by formaldehyde column measurements from space, Geophys. Res. Lett., 30(17), 1886, doi:10.1029/2003GL017336, 2003. [PDF]

• In, H.-J., D.W. Byun, R.J. Park, N.-K. Moon, S. Kim, and S. Zhong (2006), Impact of trans-boundary transport of carbonaceous aerosols on the regional air quality in the United States: A case study of the South American wildland fire of May 1998, J. Geophys. Res, submitted, 2006. [PDF]

• Liu, H., D.J. Jacob, J.E. Dibb, A.M. Fiore, and R.M. Yantosca, Constraints on the sources of tropospheric ozone from ²¹⁰Pb-⁷Be-O₃ correlations, J. Geophys. Res., 109, D07306, doi:10.1029/2003JD003988, 2004.[PDF]

• Martin, R.V., D.J. Jacob, R.M. Yantosca, Mian Chin, and Paul Ginoux, Global and Regional Decreases in Tropospheric Oxidants from Photochemical Effects of Aerosols, J. Geophys. Res., 108(D3), 4097, doi:10.1029/2002JD002622, 2003. [PDF]

• Martin, R.V., D.J. Jacob, K.V. Chance, T.P. Kurosu, P.I. Palmer, and M.J. Evans, Global inventory of nitrogen oxide emissions constrained by space-based observations of NO₂ columns, J. Geophys. Res., 108(D17), 4537, doi:10.1029/2003JD003453, 2003. [PDF]

• Xiao, Y., D.J. Jacob, J. Wang, J.A. Logan, P.I. Palmer, P. Suntharalingam, R.M. Yantosca, G.W. Sachse, D.R. Blake, D.G. Streets, Constraints on Asian and European sources of methane from CH4-C2H6-CO correlations in Asian outflow, J. Geophys. Res, 109, D15S16, 2004. [PDF]

GEOS–Chem v4–25 (29 Nov 2001)
Benchmark simulation results checked by djj (22 Dec 2001)

• updated "chem.dat" w/ new rates based on Tyndall et al 2001 (Arlene Fiore)

GEOS–Chem v4–24 (28 Nov 2001)
Benchmark simulation results checked by djj (22 Dec 2001)

• updated timing routines, now can handle any future date past 2001 (Bob Yantosca)
• minor fixes in biogenic acetone routines (Mat Evans, Randall Martin)

GEOS–Chem v4–23 (21 Nov 2001)
Benchmark simulation results checked by djj (21 Nov 2001)

• lightning NOx doubled from 3 Tg N/yr to 6 Tg N/yr (Randall Martin)

GEOS–Chem v4–22 (15 Nov 2001)
Benchmark simulation results checked by djj (18 Nov 2001)

• heterogeneous chemistry for the 7 FAST-J mineral dust size bins (Randall Martin)
• fixes to facilitate compilation on Compaq ALPHA platform (Lyatt Jaegle)
• ships w/ separate makefile for Compaq ALPHA platform (Lyatt Jaegle)
• added some more parallel DO loops to routines (airqnt, rdust) (Randall Martin)
• removed obsolete code, updated comments, cosmetic changes (Randall Martin)

GEOS–Chem v4–21 (29 Oct 2001)

• TPCORE pressure fixer now included in "tpcore_mod.f" (Brendan Field)
• text handling subroutines now bundled into "charpak_mod.f" (Bob Yantosca)
• use routines from "transfer_mod.f" in a couple more places (Bob Yantosca)
• deleted obsolete code from prior to v4–20 updated comments, cosmetic changes

GEOS–Chem v4–20 (15 Oct 2001)

• now use routines from "transfer_mod.f" to copy and resize data blocks
• many arrays now sized (IIPAR,JJPAR,LLPAR) instead of (IGLOB,JGLOB,LGLOB)
• eliminated IGCMPAR, JGCMPAR, LGCMPAR parameters; AVGF, PW arrays
• XTRA2(I,J,5) is now just XTRA2(I,J)
• AVGW is now an allocatable array instead of a common-block array
• eliminated unnecessary variables in "chemdr.f", "partition.f", etc
• compute optical depth and surface temp correctly for 1998 GEOS-3 fields
• now call GET_TAU0 from "bpch3_mod.f" w/ 3 arguments updated comments, cosmetic changes

Papers based on GEOS–Chem v4–20:

• Heald, Colette L., Daniel J. Jacob, Paul I. Palmer, Mathew J. Evans, Glen W. Sachse, Hanwant B. Singh and Donald R. Blake, Biomass burning emission inventory with daily resolution: application to aircraft observations of Asian outflow, J. Geophys. Res., 108(D4), 8368, doi:10.1029/2002JD002732, 2003. [PDF]

• Jones, D.B.A., K.W. Bowman, P.I. Palmer, J.R.Worden, D.J. Jacob, R.N. Hoffman, I. Bey, and R.M. Yantosca, Potential of observations from the Tropospheric Emission Spectrometer to constrain continental sources of carbon monoxide, J. Geophys. Res., 108(D24), 4789, doi:10.1029/2003JD003702, 2003. [PDF]

• Worden, J.R., K.W. Bowman, and D.B.A. Jones, Characterization of Atmospheric Profile Retrievals From Limb Sounding Observations of an Inhomogeneous Atmosphere, J. Quant. Spectrosc. Radiat. Transfer, 86, doi:10.1016/S0022-4073(03)00274-7, 2004. [PDF]

GEOS–Chem v4–19 (24 Sep 2001)

• biogenic acetone emission fluxes (following Jacob et al 2001)
• isoprene emission from grass and methyl butenol emission from isoprene
• ND11 diagnostic for biogenic acetone sources/sinks
• anthro C3H8 and C2H6 emissions scaled from natural gas emissions
• bug fix: tagged CO now stores CO sources/sinks in tracer #1 properly
• other minor fixes, updated comments

GEOS–Chem v4–18 (31 Aug 2001)
Benchmark simulation results checked by djj (31 Aug 2001)

• bug fix: scale biomass CO by 5% instead of 7.4% for SMVGEAR
• bug fix: scale biomass CO by 11% instesd of 16.3% for Tagged CO run
• added code to read GEOS-3 optical depths from disk
• GET_TAU0 can now return daily TAU0's instead of just monthly TAU0's
• commented out use of 1996 biogenic fields for Tagged CO run
• minor bug fixes and cosmetic changes

GEOS–Chem v4–17 (20 Jul 2001)
Benchmark simulation results checked by djj (31 Aug 2001)

• TPCORE routines bundled into "tpcore_mod.f" for easier bookkeeping
• OpenMP directives for all parallel loops
• special code added for DEC/COMPAQ and LINUX platforms
• minor improvements, updated comments, cosmetic changes

GEOS–Chem v4–16 (17 Jun 2001)
Benchmark simulation results checked by djj (22 Jun 2001)

• surface emissions now distributed thru boundary layer for SMVGEAR
• added ND12 diagnostic: fraction of PBL occupied by level L
• many initialization routines now read files directly from DATA_DIR
• read newly reprocessed files for stratospheric NOy flux
• added fixes to run GEOS-3 with SMVGEAR: lightning, P(NOy), etc.
• added updates to single and multi-tracer tagged-Ox runs (from amf)
• extra error checking in several routines
• bug fix:biomass PRPE isn't multiplied by 3 anymore
• bug fix: anthro C2H6 is now read in correctly
• updated comments, cosmetic changes, eliminated obsolete code

Papers based on GEOS–Chem v4–16:

• A. M. Fiore, D.J. Jacob, B.D. Field, D.G. Streets, S. Fernandes, and C. Jang, Linking air pollution and climate change: The case for controlling methane, Geophys. Res. Lett., 29 (19), 1919. doi:10.1029/2002GL015601, 2002. [Abstract] [PDF]

• Li, Q., D.J. Jacob, T.D. Fairlie, H. Liu, R.M. Yantosca, and R.V. Martin, Stratospheric versus pollution influences on ozone at Bermuda: Reconciling past analyses, J. Geophys. Res., 107 (D22), 4611, doi: 10.1029/2002JD002138, 2002. [Abstract] [PDF] [PS]

• Martin, R.V., A. Fiore, and A. Van Donkelaar, Space-based diagnosis of surface ozone sensitivity to anthropogenic emissions, Geophys. Res. Lett, 31, L06120, doi:10.1029/2004GL019416, 2004.[PDF]

GEOS–Chem v4–15 (15 Jun 2001)
Benchmark simulation results checked by djj (22 Jun 2001)

• updated fossil fuel emissions (jal/rmy/acs 4/01)
• correction factors for CO-OH parameterization (bnd 6/01)
• bug fix: scale annual biomass burning emissions to TOMSAI (bnd 6/01)
• eliminated much obsolete, commented out code
• fixed ND21 optical depth diagnostic for GEOS-3 met fields
• bug fix for GEOS-3 fields in single tracer Ox chemistry routine
• collated Rn-Pb-Be routines into a F90 module ("RnPbBe_mod.f")

GEOS–Chem v4–14 (18 Apr 2001)

• biofuel emissions: NOx, CO, ALK4, ACET, MEK, ALD2, PRPE, C3H8, CH3O, C2H6
• biofuel CO enhanced by 8.6% (full chem) or 18.9% (tagged CO chem)
• biomass CO enhanced by 7.4% (full chem) or 16.3% (tagged CO chem)
• improvements to "biomass_mod.f", "biofuel_mod.f", "tracerid.f"
• ND34 diagnostic for biofuel emissions
• logical switch LWAIT for unzipping met fields in the foreground
• support for 1998 GEOS-3 met fields extra error checking
• updated comments, cosmetic changes

GEOS–Chem v4–13 (09 Mar 2001)
Benchmark simulation results checked by djj (11 Jun 2001)

• scaling of monoterpenes to leaf area indices ("emmonot.f")
• CH4 emissions & chemistry routines ("global_ch4_mod.f")
• new C-preprocessor switches for SGI and DEC/Compaq platforms ("define.h")
• new routines for trapping NaN's and infinities ("error_mod.f")
• error checks every hour for STT array (in "main.f")
• restored CO scale factor to 1.0 ("emfossil.f")

Papers based on GEOS–Chem v4–13:

• Liu, Hongyu, Daniel J. Jacob, Isabelle Bey, Robert M. Yantosca, Bryan N. Duncan, and Glen W. Sachse, Transport pathways for Asian pollution outflow over the Pacific: Interannual and seasonal variations, J. Geophys. Res., 108, 8786, doi 10.1029/2002JD003102, 2003. [PDF]

GEOS–Chem v4–12 (12 Jan 2001)

• 8% more anthropogenic CO emissions (from VOC's) in full chemistry run
• CO emissions from MONOTERPENES and CH3OH in full chemistry run
• 20% more anthropogenic CO emissions (from VOC's) in tagged-co and CO-OH runs
• 10% more biomass CO emissions (from VOC's) in tagged-co and CO-OH runs
• 10% more biofuel CO emissions (from VOC's) in tagged-co and CO-OH runs
• CO emissions from CH3OH and MONOTERPENES in tagged CO and CO-OH runs
• Yearly and longitudinal gradients of CH4 in tagged-co and CO-OH runs
• Added CO from MONOTERPENES to ND29, ND46 diagnostics
• Added CO from CH3OH to ND29 diagnostic
• Other minor bug fixes, updated comments

Papers based on GEOS–Chem v4–12:

• Li, Q., D. J. Jacob, I. Bey, P. I. Palmer, B. N. Duncan, B. D. Field, R. V. Martin, A. M. Fiore, R. M. Yantosca, D. D. Parrish, P. G. Simmonds, and S. J. Oltmans, Transatlantic transport of pollution and its effects on surface ozone in Europe and North America, J. Geophys. Res., 107 (D13), 10.1029/2001JD001422, 2002. [Abstract] [PS]

GEOS–Chem v4–11 (21 Dec 2000)

• Reset parameters to allow for peroxy radical mech. ("comode.h", "cmn_fj.h")
• Removed obsolete, commented-out code from several routines

Papers based on GEOS–Chem v4–11:

• Chandra, S., J.R. Ziemke, P.K. Bhartia, and R.V. Martin, Tropical tropospheric ozone: Implications for biomass burning, J. Geophys. Res., 10.1029/2001JD000447, 2002.  [PDF]

• Chandra, S., J.R. Ziemke, and R.V. Martin, Tropospheric ozone at tropical and middle latitudes derived from TOMS/MLS residual:Comparison with a global model, J. Geophys. Res., 108 (D9), 4291, doi 10.1029/2001JD002912, 2003. [PDF]

• Martin, R.V., D.J. Jacob, J.A. Logan, I. Bey, R.M. Yantosca, A.C. Staudt, Q. Li, A.M. Fiore, B.N. Duncan, H. Liu, P. Ginoux, and V. Thouret, Interpretation of TOMS observations of tropical tropospheric ozone with a global model and in-situ observations, J. Geophys. Res., 107(D18), 4351, 10.1029/2001JD001480, 2002. [PDF] [Efficiency Correction]

• Martin, R.V., K. Chance, D.J. Jacob, T.P. Kurosu, R.J.D. Spurr, E. Bucsela, J.F. Gleason, P.I. Palmer, I. Bey, A.M. Fiore, Q. Li, R.M. Yantosca, and R.B.A. Koelemeijer, An improved retrieval of tropospheric nitrogen dioxide from GOME, J. Geophys. Res., 10.1029/2001JD001027, 2002. [PDF] [Retrieved Columns (July 1996)]  [Retrieved Columns (TRACE-P)]

• Martin, R.V., D.J. Jacob, J.A. Logan, I. Bey, R.M. Yantosca, A.C. Staudt, Q. Li, A.M. Fiore, B.N. Duncan, H. Liu, P. Ginoux, and V. Thouret, Interpretation of TOMS observations of tropical tropospheric ozone with a global model and in-situ observations, J. Geophys. Res., 107 (D18), 4351, 10.1029/2001JD001480, 2002. [PDF]  [Efficiency Correction]

GEOS–Chem v4–10 (19 Dec 2000)

• Removed obsolete ASCII punch file format ("diag3.f", "diag7.f")
• Various minor bug fixes for diagnostic output
• Now save ND65 output only up to tropopause ("diag3.f", "ndxx_setup.f")
• Save Ox to punch file at start & end of run for STDRUN testing ("main.f")
• Updated Ox and NOy fluxes for new TPCORE ("upbdflx_o3.f", "upbdflx_noy.f")
• Now does strat chem in a parallel DO-loop ("schem.f")

GEOS–Chem v4–09 (04 Dec 2000)

• Updated afternoon timeseries code ("diag51_mod.f")
• Updated CO-OH code from bnd (as of 10/31/00)
• Declared more SMVGEAR arrays allocatable ("comode_mod.f")
• Extra error checks when reading met fields ("dao_read_mod.f")
• Proper aerosol dust file selection for 1996 and 1997 ("rdust.f", "chemdr.f")
• Bug Fix: WASHFRAC * F is now applied for soluble gases ("wetdep.f")
• Bug Fix: Use correct N Pole boundary for TOMS AI scaling ("biomass_mod.f")

GEOS–Chem v4–08 (19 Oct 2000)

• mineral dust optical depths for FAST-J
• new decision tree for biomass burning options updated CO-OH parameterization code (from bnd)
• now reads SLP field from GEOS-3 data files
• redimension some diagnostic arrays to save memory minor bug fixes, cosmetic changes

GEOS–Chem v4–07 (29 Sep 2000)

• interannual variability for biomass burning from TOMS AI data
• mass flux diagnostics for TPCORE v. 7.1 (ND24, ND25, ND26)
• resized arrays for chem mechanism w/o peroxy radicals ("comode.h", "cmn_fj.h")

GEOS–Chem v4–06 (18 Sep 2000)

• new biomass burning emissions ("biomass_mod.f")
• new biofuel burning emissions for CO & NOx ("biofuel_mod.f")
• more checks for EOF condition when reading data from disk

Papers based on GEOS–Chem v4–06:

• Li, Q., D. J. Jacob, J. A. Logan, I. Bey, R. M. Yantosca, H. Liu, R. V. Martin,A. M. Fiore, B. D. Field, B. N. Duncan, and V. Thouret, A tropospheric ozone maximum over the Middle East, Geophys. Res. Lett., 28, 3235-3238, 2001. [PS]

• Liu, H., D.J. Jacob, L.Y. Chan, S.J. Oltmans, I. Bey, R.M. Yantosca, J.M. Harris, B.N. Duncan, and R.V. Martin, Sources of tropospheric ozone along the Asian Pacific Rim: An analysis of ozonesonde observations, J. Geophys. Res., doi:10.1029/2001JD002005, 2002 [PDF]

• Liu, H., D.J. Jacob, J.E. Dibb, A.M. Fiore, and R.M. Yantosca, Constraints on the sources of tropospheric ozone from ²¹⁰Pb-⁷Be-O₃ correlations, J. Geophys. Res., 109, D07306, doi:10.1029/2003JD003988, 2004. [PDF]

GEOS–Chem v4–05 (11 Sep 2000)

• added CLDMAS field to ND66 diagnostic
• added extra error-checking for EOF condition ("dao_read_mod.f")
• removed the deliquescence criteria for aerosols ("calcrate.f")
• removed a lot of obsolete code other minor cosmetic changes

GEOS–Chem v4–04 (31 Aug 2000)

• new module for reading in global OH fields ("global_oh_mod.f")
• new module for tagged CO simulation ("tagged_co_mod.f")
• new module for reading in GEIA emissions ("geia_mod.f")
• code for reading in GEOS-3 met fields ("dao_mod.f", "dao_read_mod.f")
• added more utility routines to F90 modules ("bpch3_mod.f", "time_mod.f")
• elimination of lots of commented out, obsolete code
• elimination of duplicate mp and 1p files for parallel processing
• redesigned Makefile

GEOS–Chem v4–03 (18 Jul 2000)

• new module for storing & manipulating DAO met field data ("dao_mod.f")
• new module for reading DAO met data from disk ("dao_read_mod.f")
• new module for date/time utilities and Y2K compliance ("time_mod.f")
• new module for holding large SMVGEAR arrays ("comode_mod.f")
• new module for binary punch file utilities ("bpch3_mod.f")
• removal of obsolete common-block header files for met field data
• additional error checking for reading/writing restart files
• additional error checking for 3-D timeseries diagnostics
• additional internal routines in various source code files
• cosmetic changes, updated comments

GEOS–Chem v4–02 (21 Jun 2000)

• Sulfate chemistry routines from GSFC GOCART model ("sulfate_mod.f")
• Diagnostics for sulfur emissions and production
• Removed obsolete code from some routines ( "ctm_flush.f", "open_files.f", "close_files.f" )
• Minor bug fixes & improvements ("airqnt.f", "diag_xtp.f", "diag_ytp.f", "diag_3.f", "diag51.f", "init_scav.f" )

GEOS–Chem v4–01 (11 May 2000)

• Parallel transport code (TPCORE v. 7.1)
• Parallel cloud convection code ("nfcldmx.f")
• Parallel unit conversion code ("convert_units.f")
• Parallel diagnostic archiving ("diag1.f")
• Bug fix: split MIEDX into a separate common block ("jv_cmn.h")
• Bug fix: cap RDLOSS to prevent negative tracer ("schem.f")
• Bug fix: suppress drydep over aerodynamically smooth regions ("depvel.f")
• Bug fix: skip archiving for inactive or dead drydep species ("dryflx.f")
• Now archive O3 and NO2 for movie diagnostics, minor bug fixes ("diag49.f")
• Now archive NO2 as for movie diagnostics ("diag51.f")
• Error checking for negatives and NaN's ("smvgear.f", "make_wind10m.f")

GEOS–Chem v3–11 (25 Apr 2000)

• Redimensioned STT from NNPAR+3 to NNPAR (& eliminated obsolete diagnostics)
• Error checking for NTRACE in "input.f"

GEOS–Chem v3–10 (20 Apr 2000)

• New chemistry mechanism w/ peroxy radical recycling (Arlene Fiore)

GEOS–Chem v3–09 (19 Apr 2000)

• Code for CO simulation with parameterized OH (GEOSCO)
• Error checking for negative dry deposition velocities
• Bug fix: now accumulate properly into EMISRR(I,J,IDEACET) in "emissdr.f"
• Removal of obsolete code & comments from previous revisions
• Updated comments, cosmetic changes

GEOS–Chem v3–08 (13 Apr 2000)

• Elimination of ND63 diagnostic
• Commented out calls to "diag0.f"
• Bug fix for ND47 diagnostic in "diag3.f"
• Updated comments, cosmetic changes

GEOS–Chem v3–07 (29 Mar 2000)

• Allocatable diagnostic arrays for ALL diagnostics
• Updated CH3I emissions code (reads aqueous CH3I from binary punch file)
• Improved STOP 700 error output in "smvgear.f"

GEOS–Chem v3–06 (16 Mar 2000)

• New wet deposition & wet scavenging algorithm (Jacob et al, 2000)
• PTOP parameter in "CMN_SIZE" (instead of in common block "CMN")
• OH fields now read from binary punch file for
• Tagged CO run C-Preprocessor switch "LSLOWJ" for SLOW-J photolysis
• allocatable arrays for diagnostics ND16, ND17, ND18, ND31, ND33, ND35, ND39, AD67, AD69
• Updated version of "diag51.f", with DO-loops in the optimal order
• Other minor bug fixes & cosmetic changes

GEOS–Chem v3–05 (8 Feb 2000)

• Monthly mean UV albedoes for FAST-J photolysis
• Fixes for ND27, ND48 diagnostics in "diag3.f" and "diag48.f"
• Some reorganization of code in "main.f" into internal subroutines
• Flushing of stdout buffer (unit 6) before halting with I/O errors
• Other minor cosmetic changes in "chemhcn.f", "cleanup.f", "diag_mod.f"

GEOS–Chem v3–04 (1 February 2000)

• ND65 (prod-loss) diagnostics in "chemco_decay.f"
• Extra error-checking in "setup.f"
• Other fixes in "woodburn.f", "upbdflx_noy.f", "fillfields.f"

GEOS–Chem v3–03 (12 January 2000)

• Updated ND27 cross-tropopause flux diagnostic Minor bug fixes and cosmetic changes

Papers based on GEOS–Chem v3–03:

• Fiore, A.M., D.J. Jacob, I. Bey, R.M. Yantosca, B.D. Field, A.C. Fusco, and J.G. Wilkinson, Background ozone over the United States in summer: origin,trend, and contribution to pollution episodes, J. Geophys. Res., 107(D15), 10.1029/2001JD000982, 2002.  [Abstract] [PDF]

• Fiore, Arlene M., Daniel J. Jacob, Rohit Mathur, Randall V. Martin, Application of empirical orthogonal functions to evaluate ozone simulations for the eastern United States with regional and global models, J. Geophys. Res., 108, 4431, doi: 10.1029/2002JD003151, 2003 [Abstract] [PDF]

• Jacob, D.J., B.D. Field, E. Jin, I. Bey, Q. Li, J.A. Logan, and R.M. Yantosca, Atmospheric budget of acetone, Geophys. Res. Lett., 10.1029/2001JD000694, 2002.  [Abstract]  [PDF] 

GEOS–Chem v3–02 (6 January 2000)

• Flux boundary conditions for O3 and NOy @ top of model
• Suppression of HNO3 simple chemistry/photolysis in "schem.f"
• Dynamically allocatable arrays for ND20 and ND50 diagnostics
• Improved error checking for ND48 timeseries input
• Addition of surface pressure and temperature to ND49 diagnostic
• Addition of pure ozone to ND50 diagnostic
• Minor updates for wet deposition in "rainout.f" and "nfcldmx.f"
• Various bug fixes and cosmetic changes

Papers based on GEOS–Chem v3–02:

• Bey, I., D. J. Jacob, R. M. Yantosca, J. A. Logan, B. Field, A. M. Fiore, Q. Li, H. Liu, L. J. Mickley, and M. Schultz, Global modeling of tropospheric chemistry with assimilated meteorology: Model description and evaluation, J. Geophys. Res., 106, 23,073-23,096, 2001. [Abstract] [PDF]

• Bey I., D. J. Jacob, J. A. Logan, R. M. Yantosca, Asian chemical outflow to the Pacific: origins, pathways and budgets, J. Geophys. Res., 106, 23,097-23,114, 2001. [Abstract] [PDF]

• Li, Q., D.J. Jacob, I. Bey, R.M. Yantosca, Y. Zhao, and Y. Kondo, Atmospheric hydrogen cyanide (HCN): Biomass burning source, ocean sink? Geophys. Res. Lett., 27, 357-360, 2000. [Abstract] [PDF]

GEOS–Chem v3–01 (13 Dec 1999)

• annual mean tropopause code SMVGEAR chemistry below annual mean tropopause
• SChem chemistry above annual mean tropopause
• allocatable array for ND41 diagnostic
• "read_bpch2.f" -- used to read input data from binary punch files

GEOS–Chem v2–13 (3 Dec 1999)

• ND55 diagnostic for tropopause level, height, pressure
• dynamically allocatable array AD55 for tropopause diagnostics
• new biomass burning emission factors for C2H6, C3H8, CH3O

GEOS–Chem v2–12 (1 Dec 1999)

• Dynamically allocatable arrays for the following diagnostics:
     ND14, ND15, ND21, ND22, ND23, ND24, ND25, ND26,
     ND38, ND39, ND43, ND45, ND47, ND48, ND66, ND68

GEOS–Chem v2–11 (24 Nov 1999)

• Code for single-tracer Ox chemistry (NSRCX == 6)
• Dry deposition of NO2 and O3 for single-tracer Ox chemistry
• Renamed categories for drydep fluxes and velocities
• Updated rdaerosol.f, which reads binary punch file format
• Updated upbdflx, now divides strat flux of O3 by 4
• Updated comments, cosmetic changes

GEOS–Chem v2–10 (19 Nov 1999)

• ND41 diagnostic for 1-4 PM PBL height
• ND51 diagnostic for 1-4 PM timeseries
• DIAG_MOD: declares some diagnostic arrays as allocatable
• Minor fixes and updated comments

GEOS–Chem v2–09 (15 Nov 1999)

• Mass-Flux diagnostics in TPCORE, NFCLDMX, TURBDAY
• Modified wet deposition routines
• Modified Reynolds' # criterion in "depvel.f"
• Updated comments and removed obsolete code

GEOS–Chem v2–08 (9 Nov 1999)

• Tagged CO subroutines (NSRCX = 7)
• Minor bug fixes for diagnostics
• Logical flags LSPLIT, LMONOT now read by "setup.f"
• Added fixes to "readfields.f" and "fillfields.f" for 2 x 2.5

GEOS–Chem v2–07 (22 Oct 1999)

• Updated soil NOx emissions code
• Bug fix for ND32 binary punch file output
• Cosmetic changes and updated comments

GEOS–Chem v2–06 (18 Oct 1999)

• Fixes in order to properly read met fields for 1996 and beyond
• Updated chemical mechanism code (new "chemset.f")
• Various minor bug fixes
• Several cosmetic changes

GEOS–Chem v2–05 (5 Oct 1999)

• Installed FAST-J v. 3.0 routines
• Minor cosmetic changes

GEOS–Chem v2–04 (21 Sep 1999)

• Bug fixes in setmodel.f, setup.f, and read49.f

GEOS–Chem v2–02 (11 Aug 1999)

• Added acetone source from monoterpenes
• Added code for 2 x 2.5 and GEOS-STRAT grids
• Now supports binary punch file v. 2.0
• Now supports blocking of large arrays with preprocessor switches Improved diagnostics and I/O error trapping
• Added latest alternate chemistry codes (CH3I, Rn/Pb/Be, HCN, O3 P-L)

Papers based on GEOS–Chem v2–02:

• Liu, H., D.J. Jacob, I. Bey, and R.M. Yantosca, Constraints from ²¹⁰Pb and ⁷Be on wet deposition and transporting a global threee-dimensional chemical tracer model driven by assimilated meteorological fields, J. Geophys. Res., 106, 12,109 - 12,128, 2001. [Abstract] [PS]

GEOS–Chem v2–01–01 (6 May 1999)

• Included option to choose Kzz or TURBDAY for BL mixing
• Fixed call to TPCORE, we don't reset pressures afterwards
• Now use original TPCORE v. 4.1, from S-J Lin Made fixes to timeseries diagnostics & other minor fixes

GEOS–Chem v2–01 (22 Feb 1999)

• Incorporated the updated merge file
• Fixed biomass burning emissions
• Added new diagnostics (chemical prod/loss, NO fields, RH in diag48, flux from the stratosphere, timeseries for geographical domain)
• Changed flux from the stratosphere
• Changed diag48 to automatically assign stations from level 1 to level indicated in inptr.ctm
• Modified fast-J subroutines to calculate the effect of changing Earth-Sun distance during the year and acetone pressure dependance
• Add flag s for new chemistry runs (HCN, CO, etc...)
• Changed the archiving time for tracer fields Changed the scavenging in convective events

GEOS–Chem v1–09 (11 Jan 1999)

• Now use FRCLND instead of TCRIJ for CH3I emissions
• Also minor changes to chemrn.f and chemch3i.f

GEOS–Chem v1–08 (25 Nov 1998)

• Added J-value lookup table
• If NSRCX=1 will do Radon chemistry
• If NSRCX=2 will do CH3I chemistry

GEOS–Chem v1–05 (02 Oct 1998)

• Fixed negative J-value bugs in fast-J

GEOS–Chem v1–04–02–01 (29 Sep 1998)

• Bug fixes in FAST-J interface

GEOS–Chem v1–04–01 (28 Sep 1998)

• Minor fixes

GEOS–Chem v1–04 (25 Sep 1998)

• Added UCI FAST-J photolysis code Use separate counter array for J-value diagnostic

GEOS–Chem v1–02–01 (17 Sep 1998)

• Now uses value of CLDMAS to diagnose the occurrences of deep convective clouds, and scales TAURO accordingly (NOTE: This was for testing only.)
• Also uses F90 syntax for declarations.

GEOS–Chem v1–02 (11 Sep 1998)

• Added cloud fractions to ND21 diagnostic

GEOS–Chem v1–01–02 (25 Sep 1998)

• Order of diagnostics is now print, write restart file, check for end of run, accumulate

GEOS–Chem v1–01–01 (17 Sep 1998)

• Now passes CLDMAS to OPTDEPTH, so that it can diagnose occurrences of deep convective clouds

GEOS–Chem v1–01 (10 Sep 1998)

• Initial revision