GEOS-Chem 12

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GEOS-Chem v11-02-final will also carry the designation GEOS-Chem 12.0.0. We are migrating to a purely numeric versioning system in order to adhere more closely to software development best practices. For a complete description of the new versioning system, please see our GEOS-Chem version numbering system wiki page.

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Version history

The table below shows the previous, current, and successive major GEOS-Chem versions:

Previous major release	This version in development	Next major release
GEOS-Chem v11-02 (aka 12.0.0)	GEOS-Chem 12	GEOS-Chem 13
TBD	TBD	TBD
View v11-02 benchmark history	View GEOS-Chem 12 benchmark history	TBD

The sections below describe each GEOS-Chem feature version and GEOS-Chem patch version belonging to the GEOS-Chem 12 series. Each feature version carries the tag 12.Y.0, which indicates that the version will be (or has been) validated with a 1-month benchmark simulation (and one or more 1-year benchmark simulations if necessary). Each patch version carries the tag 12.Y.Z, which denotes that the version preserves backwards-compatibility with the prior feature version 12.Y.0. For more information, please see our GEOS-Chem version numbering system wiki page.

In the pipeline

Several GEOS-Chem updates have been proposed by the relevant Working Groups, but have not yet been assigned to a specific GEOS-Chem version. For a complete list of these updates, please visit our GEOS-Chem model development priorities wiki page.

GEOS-Chem 12.3.0

The items listed below are slated to be included in GEOS-Chem 12.3.0. This is a feature release which will be validated with a 1-month benchmark simulation.

Feature	Submitted by	Type	Status
Features affecting the full-chemistry simulation:
Update ISORROPIA from v2.0 to v2.2, in order to remove persistent noise in output	Seb Eastham (Harvard)	Science	Delivered to GCST (May 2017)
Update MODIS LAI fields for 2005-2016 using Yuan et al. (2011)	Jenny Fisher (Wollongong) Barron Henderson (US EPA)	Science	Will require reworking of LAI regridding in GEOS-Chem Classic and pre-processing land map data
Extend UCX into the mesosphere	Sebastian Eastham (MIT)	Science
OMI-based Volcanic emissions 2005-2012	Cui Ge (U. Iowa) Jun Wang (U. Iowa)	Science	Working with developers to obtain alternate data for Oct-Dec 2012.

GEOS-Chem 12.2.0

The items listed below are slated to be included in GEOS-Chem 12.2.0. This is a feature release which will be benchmarked with a 1-month benchmark simulation and a 1-year Rn-Pb-Be benchmark simulation.

Feature	Submitted by	Type	Status
Features NOT affecting the full-chemistry simulation:
Common set of tracers in GEOS-Chem and GEOS	Transport WG GCST	Benchmarking	A set of passive species will be added to the GEOS-Chem Rn-Pb-Be benchmark simulation. This will facilitate comparisons between GEOS-Chem "Classic" and/or GCHP vs. the NASA GEOS-DAS system.

GEOS-Chem 12.1.0

The items listed below are slated to be included in GEOS-Chem 12.1.0. This is a feature release which will be validated with a 1-month benchmark simulation.

Feature	Submitted by	Type	Status
Features affecting the full-chemistry simulation:
FlexGrid: Use HEMCO to read met fields and enable nested simulations over any custom domains	Jiawei Zhuang (Harvard) Jintai Lin (PKU)	Structural	NOTE: FlexGrid might result in slight differences in met fields w/r/t the current regridding method. This could have an impact on the full-chemistry simulations.
Anthropogenic PM2.5 dust source	Sajeev Philip (Dalhousie)	Science	Need to fix an under-the-hood issue in HEMCO that makes this update yield 1200 Tg of dust.
NetCDF Output Phase 3b: Updates to eliminate differences between single and multi-segmented GEOS-Chem runs	GCST Christoph Keller	Bug Fix & Structural
Features NOT affecting the full-chemistry simulation:
Updated flux diagnostics	Chris Holmes (Florida State) GCST	Structural/ Benchmarking

GEOS-Chem 12.0.0

In order to transition to a new, purely numeric versioning system, the GEOS-Chem v12.0.0 designation refers to the GEOS-Chem v11-02-final release version.

For more information about our new GEOS-Chem versioning system, please see our GEOS-Chem version numbering system wiki page.

--Bob Yantosca (talk) 15:35, 20 June 2018 (UTC)

New data directories

The following HEMCO data directories have been added or updated for GEOS-Chem 12. You will have to download the directories relevant to your simulation.

Inventory	What was added?	When added?	Directory
TBD

Validation

In this section we provide information about the benchmarks and tests that we have done to validate GEOS-Chem v11-03.

1-month and 1-year benchmarks

For complete information about the benchmark simulations used to validate GEOS-Chem v11-03, please see our GEOS-Chem v11-03 benchmark history wiki page.

Unit tests for GEOS-Chem 12

We perform a full set of unit tests on GEOS-Chem on an almost daily basis. These tests ensure that each new feature being added does not break any existing functionality.

Here are the unit tests that we ran before submitting 1-month benchmark simulation for v11-03. Click on the links below to see the results from each set of unit tests:

Unit test	Date
TBD

Previous issues now resolved in GEOS-Chem 12

The following bugs and/or technical issues have been resolved in v11-03.

Outstanding issues not yet resolved in GEOS-Chem 12

The following known issues are slated to be fixed in GEOS-Chem 12:

FlexChem bug fix: do not zero ACTA, EOH, HCOOH

This fix will be included in GEOS-Chem 12.

Katie Travis wrote:

I am working on a VOC simulation, and noticed that in my copy of v11-02f, the following species are set to zero in two places:

     ! Zero certain species
     C(ind_ACTA) = 0.e0_dp
     C(ind_EOH) = 0.e0_dp
     C(ind_HCOOH) = 0.e0_dp

And

  C(ind_ACTA)  = 0.0_dp
  C(ind_HCOOH) = 0.0_dp

Since none of these species are fixed in Tropchem.eqn, shouldn’t they NOT be set to zero?

Mike Long wrote:'

I think the code should be removed. This must have been a patch added to maintain parity with SMVGEAR w/o anticipating that the species would become active.

--Bob Yantosca (talk) 16:19, 17 May 2018 (UTC)

Avoid double counting CEDS and GEIA NH3 biofuel emissions

This fix will be included GEOS-Chem 12.

Eloise Marais wrote:

If CEDS includes NH3 emissions, then this will be double counting. I recommend using CEDS, as GEIA is very out of date (1998 according to the HEMCO configuration file I have).

Daniel Jacob replied:

We should use the GEIA NH3 natural emission inventory (1° x 1° file from Eleanor Morris) but not the GEIA NH3 biofuel inventory.

--Bob Yantosca (talk) 16:33, 17 May 2018 (UTC)