GEOS-Chem model development priorities

On this page we list the current priorities for GEOS-Chem development. This list is continuously updated based on code readiness and input from the Working Groups and the Steering Committee.

We also invite you to view our GEOS-Chem Support Team project management board on Trello.com, which shows the current GCST workflow.

Priorities assigned to upcoming GEOS-Chem versions

12.1.0

This version is currently in development. See the GEOS-Chem 12 wiki page for details.

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.

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
Updated PFT file for MEGAN	Jenny Fisher (Wollongong) Dylan Millet (UMN)	Science	Delivered to GCST (May 2018)
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.

Priorities not yet assigned to a particular version

The following items have been identified as priorities for GEOS-Chem, but have not yet been assigned to a particular GEOS-Chem version.

Ready to go in

Feature	Submitted by	Type	Status
Emissions and surface fluxes updates
Carbon bottom up fluxes: anthro, ocean, land	Kevin Bowman (JPL)	Science	Kevin Bowman wrote: This is a a list of data archived from CMS-Flux that provides bottom up fluxes. These have been generated for the years 2010-2012 and are ready to go now. The key datasets are: CMSFluxFire CMSFluxFossilfuel CMSFluxNEE CMSFluxOcean
Wet deposition updates
Wet deposition parameterizations: pH dependency, Henry's law coefficients, etc.	Sarah Safieddine (MIT) GCST	Science
Aerosol updates
Sea salt aerosol alkalinity	Qianjie Chen (UW) Becky Alexander (UW) Xuan Wang (Harvard)	Science	UW version delivered to GCST (Nov 2017)
VBS SOA option	Rokjin Park (SNU)	Science	Code has been implemented in the ancient v9-01-02 version. Bringing this up to the current SOA model (simple SOA, complex SOA) will likely involve significant effort.
Specialty simulation updates
AMAP/UNEP 2035 for Hg simulation	Helene Angot (MIT)	Science	Data is available, but has not been transferred to GCST yet
Oxidant fields from v10 for 2006-2012 3D chemical source for CO2, CO OH for tagged CO & CH4	Dylan Jones (UofT)	Science	Will make data files available on ftp site
Africa nested-grid for GEOS-FP and MERRA-2	Eloise Marais (U. Birmingham)	Science	Delivered to GCST (Dec 2017) Could be implemented with Jiawei Zhuang's FlexGrid
West Africa nested-grid for GEOS-FP	Mat Evans (York) Eleanor Morris (York)	Science	Could be implemented with Jiawei Zhuang's FlexGrid
Tagged sulfate simulation	Becky Alexander (UW)	Science
Arsenic simulation	Shiliang Wu (MT)	Science
GCHP updates
None
Structural updates
Benchmark of stratospheric simulation	Dylan Jones (U. Toronto)	Benchmarking	1-yr benchmarks for GEOS-Chem v11-01d and later include comparisons with OSIRIS O3 Waiting on OSIRIS NO2 data Waiting on comparisons with ACE-FTS data
Add total column O3 to benchmarks	Chris Holmes (FSU) GCST	Benchmarking	Deferred until GEOS-Chem 12 Also note: GCST plans on migrating benchmark plotting code from IDL to Python in v11-03
ObsPack diagnostic as netCDF replacement for planeflight_mod.F	Andy Jacobson (NOAA/ESRL)	Structural	Delivered to GCST (May 2017)
Further structural updates to facilitate interfacing GEOS-Chem with external models (e.g. WRF, CAM, CESM)	GCST	Structural	Ongoing
Expansion of model capabilities
Archival of roughness length for temperature z0T	GCST	Met processing	Work has not yet begun

--Bob Yantosca (talk) 19:04, 2 August 2018 (UTC)

Almost there (< 6 months)

Item	Author(s)	Type	Status
Transport updates
GEOS resolution & subgrid convection	Karen Yu (Harvard)	Science	To be installed by Bob Yantosca (Harvard), tested by Tailong He (Toronto) Work to begin after GC 12.0.0 release
Chemistry updates
N2O5 hydrolysis updates	Viral Shah (UW)	Science	Defer until paper is submitted (Summer 2018) Code from v10 (SMVGEAR) needs to be translated to v11 (FlexChem); this may take some effort
H2 chemistry in UCX	Chris Holmes (FSU)	Science	Defer until paper is submitted Estimate Fall 2018 or sooner
Updated chlorine chemistry	Xuan Wang (Harvard)	Science	Defer until the paper is submitted
ND49 timeseries diagnostic for correcting ozone from the height of the lowest model level to 10m	Katie Travis (MIT)	Structural	Defer until the paper is submitted
OH + NO2 rate update	Barron Henderson (EPA)	Science
Script for checking N, C, etc. balance in chemistry mechanism	Barron Henderson (EPA)	Software	Barron Henderson wrote: The script for checking the carbon balance exists and works. Ideally, we would move some of the structures into the KPP files to codify them instead of storing them in the script itself. This would be less than 6 months. Click HERE for script
Aromatics and dicarbonyl chemistry	William Porter (MIT) Tzung-May Fu (PKU)	Science
Document chemical mechanism in KPP file	Mat Evans (York)	Structural
Diurnal variability for NH3	Henze group	Science	Daven Henze wrote: The FORTRAN code for implementing NH3 emissions diurnal variability is fairly straightforward. However, it involves calculation of some quantities that depend upon met fields in the future, and we’re unsure of how to accomplish this in a robust and elegant manner. In particular, we need to know the aerodynamic resistance and surface temperature at every emission time step over the course of a time period X, where X is the time resolution of the NH3 livestock emissions inventory being used. This is typically monthly, but I could foresee future inventories having higher resolution, so maybe we want to consider this more generically. One approach would be to pre-process this quantity at high resolution for all years, as is currently being done e.g. for dust emissions. Another would be to add code to read in this information from met files online, but this would add some i/o to the model.
Uptake of HNO3 onto coarse-mode sea salt	Prasad Kasibhatla (Duke)	Science
Photolysis of NITs	Prasad Kasibhatla (Duke)	Science
Update heterogeneous processes to address high bias in nitrate	Chris Holmes (FSU)	Science
Aerosol updates
Update to hygroscopic growth	Robyn Latimer (Dalhousie) Randall Martin (Dalhousie)	Science
Emissions updates
Grid-independent lightning NOx emissions (3-hourly)	Lee Murray (Rochester)	Science	Data has not yet been transferred to GCST
Grid-independent dust emissions (hourly)	David Ridley (MIT)	Science	Data has not yet been transferred to GCST
Grid-independent biogenic emissions (hourly)	Jintai Lin (PKU)	Science	Data has not yet been transferred to GCST
Grid-independent sea salt emissions (hourly)	Jintai Lin (PKU)	Science	Data has not yet been transferred to GCST
EPA-derived BC/OA emissions over US (1990-2012)	David Ridley (MIT) Chi Li (Dalhousie)	Science	Emissions are available but need to be formatted properly. Could be ready by Fall-Winter 2018, depending on D. Ridley's availability
FINN biomass burning emissions for 2014-2016	Barron Henderson (US EPA)	Science	Pending receipt of corrected data files
EPA NEI2011 Version EK	Zitely Tzompa-Sosa (CSU) Emily Fischer (CSU)	Science	Estimate Late 2018 or sooner
GFAS biomass burning emissions	Mat Evans (York)	Science	Mat Evans wrote: For the sake of the documentation and the wiki I think we should replicate the standard benchmark year on our system, and then switch on the GFAS emissions instead of the GFED and then have the GFAS emissions distributed by hieight. We can do that and then prepare some plots for the documentation. Estimate summer 2018.
MASAGE inventory in HEMCO as default	Fabien Paulot (NOAA/GFDL) Amos Tai (CUHK)	Science	MASAGE data is already available. GCST would need assistance from the user community to prepare HEMCO configuration files such that we do not double-count agricultural NH3 from MASAGE and other inventories. This has been the main delay. F. Paulot has left the GC community.
Non-agricultural NH3 for use with MASAGE	Amos Tai (CUHK)	Science	Waiting on data
Ocean ammonia emission inventory	Fabien Paulot (NOAA/GFDL)	Science	Data files delivered to GCST (Jan 2016) Needs to be implemented via HEMCO, which is the primary delay
Injection height for fire emissions	Juliet Zhu (CSU) Emily Fischer (CSU)	Science	Code was available in pre v9-02 (HEMCO) Code may have been ported to v11-02a but this option was not activated
Surface fluxes and land usage updates
Land cover module: Harmonized biosphere-atmosphere exchange and implementing CLM or manual land cover change experiments	Jeff Geddes (BU)	Science	Has been added into v9-02 (pre-HEMCO) Bringing this up to v11 will probably need significant effort BU group/GCST will meet summer 2018 to discuss implementation
Online O3-LAI coupling in GEOS-Chem	Amos Tai (CUHK)	Science
Wet deposition updates
Wet scavenging in mixed-phase clouds	Bo Zhang (NIA/NASA Langley)	Science	Defer until paper is published Estimate Fall 2018
Specialty simulation updates
Radon emission update	Bo Zhang (NIA/NASA Langley)	Science	Defer until paper is published Estimate Fall 2018
PCB simulation	Colin Thackray (Harvard) Carey Friedman (formerly MIT) Helen Amos (formerly Harvard)	Science
New EDGAR sectoral inventory for Hg (1970-2012)	Amanda Giang (MIT)	Science
Archive GISS met fields from RCP scenarios for community	Lee Murray (Rochester)	Science
GCHP updates
New version of MAPL	GMAO Lizzie Lundgren (GCST)	Structural
Flux ingestion	Sebastian Eastham (MIT)	Science
Structural updates
FlexGrid Stage 2: Enable nested simulations over any custom domains	Jiawei Zhuang (Harvard) Melissa Sulprizio (GCST)	Structural
Clean up SOA diagnostics	GCST	Structural	GCST has implemented many existing SOA diagnostics in netCDF GCST would need help from the community to streamline these diagnostics
Calculation consistency throughout code: surface area, HGF (via species database)	GCST	Structural
Harmonizing Henry's Law coefficients across wet and dry deposition	GCST	Science	Work not started yet. Will need input from the community.
Expansion of model capabilities
CESM-GC offline coupling in standard model + benchmark	Rokjin Park (SNU) Daniel Rothenberg (MIT)	Science	Rokjin Park says code is ready Waiting on clarification in which version this is implemented in.

--Lizzie Lundgren (talk) 15:11, 29 June 2018 (UTC)

Over the horizon (6-12 months)

Item	Author(s)	Type	Status
A snow NOx source from deep snowpack	Maria Zatko (UW) Becky Alexander (UW)	Science	Delivered to GCST (Nov 2017) Needs to be added as a HEMCO extension, but converting from ancient v9-01-01 code may take significant effort.
MEIC emissions over China (2000-2015)	Lu Shen (Harvard) Melissa Sulprizio (Harvard)	Science	Defer until MEIC paper is published
GISS-GC (ICECAP/GCAP2) in standard model + benchmark	Lee Murray (Rochester) Eric Leibensperger (SUNY Plattsburgh)	Science	Lee Murray replied: "I would say 6-12 months to be safe, but the goal is to have it done by the end of summer 2018. There will actually be very minimal updates to GEOS-Chem; most of the updates are to modify the GISS model to output MERRA2-like data, to facilitate integration with GCHP and future updates to the CTM."
GISS-GC GCHP	Lee Murray (Rochester) Pengfei Liu (Harvard) Yang Li (Harvard)	Science	Rochester and Harvard groups are coordinating, to avoid duplication of effort
CESM-GC GCHP	Seb Eastham (MIT)	Science	Seb Eastham is now the lead developer. Estimate late 2018 or early 2019; validation will take time
Additional modifications for FlexChem, including: Rebuild the pre-built chemistry mechanisms (Standard, Tropchem, SOA-SVPOA) with Kppa Add capability for custom chemistry mechanism by building KPP on-the-fly in GEOS-Chem	GCST	Structural	Mike Long, who was the principal proponent behind these updates, has since left the GC community. We are not sure who will take this over
Dynamic fire modeling/prediction	Shiliang Wu (MNT)	Science
Interannually varying ocean model BCs for Hg from ocean model	Colin Thackray (Harvard)	Science
PAH & PFCA simulations	Peter Ivatt (York) Mat Evans (York) Noelle Selin (MIT) Colin Thackray (Harvard)	Science
CH4 in full chemistry simulation	Seb Eastham (Harvard)	Science
Standard future land use maps (PFT, LAI) for RCP/CMIP6 simulations	Colette Heald (MIT) Loretta Mickley (Harvard)	Science
Archive GISS met fields from CMIP6 scenarios for community	Lee Murray (Rochester)	Science
Updates to cold-temperature deposition	Lyatt Jaegle (UW)	Science
Simple parameterization for CO2-O3 dependence of stomatal resistance	Amos Tai (CUHK)	Science
NH3 emissions over China	Lin Zhang (PKU)	Science
Using GEOS-Chem within GEOS-5	Loretta Mickley (Harvard)	Science
Carbon cycle outputs in xCO2, xCH4 as a diagnostic	Beata Bukosa (Wollongong) Dylan Jones (UofT)	Science
Seasonal EMEP emissions back to 1980	Mat Evans (York)	Science
Updates to NO2 dry deposition	Brian Boys (Dalhousie)	Science
APM update and integration with most recent GEOS-Chem version	Gan Luo (SUNY Albany)	Structural
Cosmogenic tracer production	Lee Murray (Rochester)	Science
Explore resolution-consistent dust emissions Make high-res concentrations or mass fluxes available offline, implement in met field processing	David Ridley (MIT) GCST Nested Model WG	Science
Dust emissions at nested-grid resolutions	Yuxuan Wang (U. Houston) Jun Wang (U. Iowa)	Science	Check for overlap with resolution-consistent dust emissions above
Update SO2 scavenging in convective updrafts for consistency	Duncan Fairlie (NASA/LARC)	Science
Sea salt emission from sea ice	Jiayue Huang (UW)	Science

--Bob Yantosca (talk) 19:42, 24 May 2018 (UTC)

Longer term (12-24 months)

Item	Author(s)	Type	Status
GCHP stretched grid	Jiawei Zhuang (Harvard)	Science
1/8 degree nested-grid simulations with GEOS-FP	Nested Model WG	Science	Wait for more interest
Embedding GEOS-Chem into CESM	Jean-Francois Lamarque (NCAR)	Science	NOTE: Seb Eastham is already working on this
Adjoint of carbon cycle simulation in GCHP	Kevin Bowman (JPL)	Science
Isoprene chemistry v2 (new Caltech update)	Kelvin Bates (Caltech)	Science
Contemporary land cover: developing historical and updated GEOS-Chem land cover maps based on satellite remote sensing	Jeff Geddes (BU)	Science
Farquhar-Ball-Barry model to calculate stomatal resistance	Amos Tai (CUHK) Jeff Geddes (BU)	Science
Impacts of chemistry on ecosystem/carbon cycle	Kevin Bowman (JPL) Anthony Bloom (JPL)	Science
Improved lightning emission scheme	Lee Murray (Rochester)	Science
Resolution-independent lightning NOx	Lee Murray (Rochester)	Science
Bidirectional NH3 emissions	Juliet Zhu (CSU)	Science
Country-based weekday/weekend variability for EDGAR 4.2	Lee Murray (Rochester) Christoph Keller (Harvard)	Science
Update keytone photolysis	Jared Brewer (CSU) Emily Fischer (CSU)	Science
Small alkyl nitrates	Jenny Fisher (Wollongong)	Science
YIBS-GC chemistry-biosphere-fire coupling	Loretta Mickley (Harvard) Xu Yue (IAP)	Science
Nitrogen-LAI coupling	Lin Zhang (PKU) Amos Tai (CUHK)	Science
Implementing humidity/VPD dependence of dry deposition	Jennifer Murphy (U. Toronto)	Science
SO2 wet scavenging	Duncan Fairlie (NASA Langley)	Science
Heterogeneous sulfate production	Lin Zhang (PKU) Becky Alexander (UW) Yuxuan Wang (U. Houston)	Science
MOSAIC implementation	Sebastian Eastham (Harvard)	Science
Particle size climatology	Fangqun Yu (SUNY Albany)	Science
Sea salt/dust size distribution	David Ridley (MIT) Colette Heald (MIT)	Science
Updates to GTMM	Rebecca Stern (Harvard)	Science
Tracer transport ocean	Chris Holmes (FSU)	Science
Include Hg in full chemistry simulation	Noelle Selin (MIT)	Science
Goddard seasonal weather prediction in GCHP	Kevin Bowman (JPL)	Science
Climate index diagnostics (drought, etc.)	Chemistry-ecosystems-climate WG	Structural
Joint CO/CO2/CH4 simulation	Nicholas Deutscher (U. Wollongong)	Science
Carbon coupling: oceans and terrestrial models	Chris Holmes (FSU)	Science	Ocim-pure physical transport, ECCO-Darwin ocean biogeochemistry
DMS oxidation scheme updating	Qianjie Chen (UW) Chemistry WG	Science
Limiting NH3 uptake due to OA	Rachel Silvern (Harvard)	Science
Uniformity of units throughout GEOS-Chem components	GCST	Structural

--Bob Yantosca (talk) 15:32, 23 May 2018 (UTC)