GEOS-Chem model development priorities

On this page we list the current priorities for GEOS-Chem development. This list was compiled by the user Working Groups at the last International GEOS-Chem Meeting (IGC5) in May 2011 and has been continuously updated since 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.

List of priorities as of September 2012

Items "Awaiting release" will be part of the next version release of GEOS-Chem and are actively being incorporated into the standard model and benchmarked. Other items are in different stages of readiness and will be included in future versions of the model.

Awaiting release

Item	Author(s)	Status
Expanded SOA	Havala Pye (EPA/ORD)	Delivered to GCST, awaiting implementation
Inorganic chemistry updates	Mat Evans (York)	Delivered to GCST, awaiting implementation
New soil NOx emission module	Rynda Hudman (UC Berkeley) Neil Moore (Dalhousie)	Bram Maasakkers (Eindhoven) integrated the new soil NOx emissions into the standard GEOS-Chem v9-01-03 code during his visit to Harvard for Summer 2012. Slated for GEOS-Chem v9-02.
Methyl peroxy nitrate (MPN) chemistry	Ellie Browne (UC Berkeley)	Delivered to GCST, awaiting implementation
Acid uptake on dust aerosols	T. Duncan Fairlie (NASA/LARC)	Delivered to GCST, awaiting implementation
Cloudwater pH for sulfate formation	Becky Alexander (U. Washington)	Delivered to GCST, awaiting implementation
EPA/NEI2005 Hg emissions for US	Lyatt Jaeglé (U. Washington)	Delivered to GCST, awaiting implementation
Streets future Hg emissions	Bess Corbitt (Harvard)	Delivered to GCST, awaiting implementation
Nested-grid Hg simulation	Lyatt Jaeglé (U. Washington)	Delivered to GCST, awaiting implementation
Updated Hg(0) oxidation kinetics	Bess Corbitt (Harvard) Justin Parrella (Harvard)	Delivered to GCST, awaiting implementation
Capability to use GEOS-Chem Br/BrO fields in Hg simulation	Bess Corbitt (Harvard) Justin Parrella (Harvard)	Delivered to GCST, awaiting implementation
Correction for GEOS-5 PBL heights	Sajeev Philip (Dalhousie)	Delivered to GCST, awaiting implementation
Updated Canadian NH3 inventory	Wai-Ho Lo (Dalhousie)	Delivered to GCST, awaiting implementation
RCP emission scenarios	Chris Holmes (UC Irvine)	Delivered to GCST, awaiting implementation
EDGAR v4.2 emissions for CH4 simulation	Kevin Wecht (Harvard)	Delivered to GCST, awaiting implementation
Update anthropogenic scale factors through 2010	Aaron van Donkelaar (Dalhousie)	Delivered to GCST, awaiting implementation
Update jv_spec.dat with better representation of OC growth with RH and correction to sulfate optics	David Ridley (MIT)	Delivered to GCST, awaiting implementation
POPs simulation: Polycyclic aromatic hydrocarbons	Carey Friedman (MIT)	Delivered to GCST (24 Sep 2012), awaiting implementation
Tagged sulfate and nitrate simulation	Becky Alexander (U. Washington)	Code is ready
Update to EDGAR 4 anthropogenic emissions	Qiang Zhang (Tsinghua)	Code is ready
Improved HO2 uptake by aerosol	Jingqiu Mao (NASA/GFDL)	Code is ready
Nested-grid model at 0.25° x 0.3125° resolution	Yuxuan Wang (Tsinghua)	Code is ready
High-resolution emissions for above nested-grid model	Yuxuan Wang (Tsinghua)	Code is ready
Fix RO2+HO2 rate constant	Fabien Paulot (Harvard)	globchem.dat is ready
Update Asian emissions	Qiang Zhang (Tsinghua)	Qiang Zhang wrote: Recently we have developed a new Asian emission inventory for 2008 and 2010, with 0.25 x 0.25 degree resolution. This inventory is a combination of China inventory from my group, India inventory from David Streets, Korea and Japan inventory from official data, and rest of Asia from REAS data. This inventory will be used for the coming MICS-Asia phase III and HTAP assessment. If the community would like to use the new inventory immediately in GEOS-Chem, we can implement it in couple of weeks.

--Melissa Payer 10:30, 24 September 2012 (EDT)

Almost there (< 6 months)

Item	Author(s)	Status
FAA/AEDT aircraft emissions inventory	Steven Barrett et al (MIT)	Code delivered to GCST, on hold
Longwave & shortwave RF codes for chemistry-climate	Fangqun Yu (SUNY Albany)	Fangqun Yu wrote: While the first paper on aerosol direct radiative forcing (DRF) with the CCCMa RF code has been published (Ma et al., ACP, 2012), a comparison of DRF values (clear sky vs all sky) of GEOS-Chem with those of others in AeroCom (Myhre et al., ACPD, 2012) indicates that CCCMa RF code may have underestimated the impacts of clouds on radiation... More time is needed for further simulations and evaluations. After I am happy with the RF results and if there is enough interest in the community, I will try to find time to move the APM optical calculation code and RRTMG code into v9.1.3 and handle them to GC support team for inclusion in the standard version.
APM capability for nested grid	Fangqun Yu (SUNY Albany)	Currently evaluating APM simulation with v9-01-03
Interannual lightning	Lee Murray (Harvard)
Primary marine OA emissions	Kateryna Lapina (CSU)
Implement GISS advection scheme for GISS-driven applications	GEOS-Chem Support Team
Updated dicarbonyl simulation	May Fu (Peking U.)
Satellite diagnostic for XCO2	Liang Feng (U. Edinburgh)
Improve temporal resolution of anthropogenic CO2 sources	Ray Nassar (Environment Canada)
Improvements to isoprene chemistry, standardization of Paulot Scheme	Fabien Paulot (Harvard) Eloise Marais (Harvard) Jingqiu Mao (NASA/GFDL) Mat Evans (York)
RO2+NO3 chemistry updates	Mat Evans (York)
Inhibition of N2O5 hydrolysis by aerosol nitrate	Lin Zhang (Harvard)
Improved ROOH formation and chemistry	Fabien Paulot (Harvard) Mat Evans (York)
Unified emissions pre-processor	Qiang Zhang (Tsinghua)	Qiang Zhang wrote: By now we have done EDGAR 4, and now we are tackling the VOC speciation issue. Then the next step is to incorporate several regional inventory datasets. My expertise is anthropogenic emission inventory development, so my efforts focus on how to include state-of-art research inventories in the GC model. I hope we can merge our efforts [with your efforts toward the Grid-independent Emissions Component] into one framework.
Improved operator splitting	Mauricio Santillana (Harvard)	Towards this end, we have added the Centralized chemistry time step option into GEOS-Chem v9-01-02. This makes sure that the tracer concentrations being sent into the chemistry solver are more representative of the center of the chemistry timestep, and thus are more consistent with when the photolysis gets computed. Mauricio is writing up his results for a paper to be submitted to JGR.
Replace CASA CO2 biosphere climatology with year-specific fluxes	Ray Nassar (Environment Canada) Dylan Jones (U. Toronto)	Ray Nassar wrote: SiB Fluxes are available to replace the old CASA fluxes, courtesy of Janina Messerschmidt et al. New CASA fluxes would also be good, such that the user can select options in the input.geos file.
Improved dust simulation in nested-grid model	Rokjin Park (Seoul Nat'l Univ.)	Rokjin Park wrote: We are evaluating the performance of new dust scheme over East Asia
CESM/CAM5 interface for chemistry-climate	Rokjin Park (Seoul Nat'l Univ.) Joshua Fu (U. Tennessee)	Rokjin Park wrote: CESM/CAM5 - GEOS-Chem linking tool has been developed and will be tested soon
CO2 inhibition effect for isoprene emission	Loretta Mickley (Harvard)	Amos Tai has implemented the CO2 inhibition effect and is currently testing. A manuscript is in preparation.

--Melissa Payer 10:30, 24 September 2012 (EDT)

Over the horizon (6-12 months)

Item	Author(s)	Status
Working with GEOS-5.7.2	GEOS-Chem Support Team	Initial changes already added into v9-01-03; validation is ongoing GMAO recently renamed GEOS-5.7.2 to GEOS-5.8 (aka GEOS-5 FP)
Update HCN simulation	Qian Li (U. Edinburgh) Dylan Jones (U. Toronto)
Online RT model in GEOS-Chem (integration of shortwave and longwave RRTMG)	Colette Heald, Steven Barrett and David Ridley (MIT)	Preliminary integration completed Oct 2012, testing, optimizing with planned delivery Spring 2013
Improved planeflight diagnostic	Mat Evans (York)
Chemistry diagnostics	Mat Evans (York)
3-D VOC source for tagged CO simulations	Dylan Jones (U. Toronto)
Move to 2° x 2.5° versions of GISS GCM ModelE and Model3	Loretta Mickley (Harvard)	For more information, please see the GISS Model E Memo by (Lee Murray and Loretta Mickley).
Implement IPCC AR5 scenarios	Loretta Mickley (Harvard)
Improve ocean CO2 flux	Ray Nassar (Environment Canada) Kevin Bowman (JPL)
Standardize the two-film parameterization of air-sea exchange	Hg and POPs Working Group
Model engineering - improving KPP diagnostics	Mat Evans (York) Barron Henderson (UNC) Mike Long (Harvard)

--Melissa Payer 12:23, 19 September 2012 (EDT)

Longer term (> 12 months)

Item	Author(s)	Status
Grid-independent GEOS-Chem	GEOS-Chem Support Team	We delivered the Chemistry Component to NASA/GMAO on June 1, 2012 (at the end of project Year 1). After the initial handoff, it was discovered that further technical fixes and updates were necessary. We have largely resolved these in 1-month benchmark v9-01-03p. We are currently testing the GEOS-Chem/GEOS-5 GCM interface on machines at NASA. Development of the Emissions Component will be the focus of Year 2 of the project. Much of this work will be done by Christoph Keller (Harvard). Our goal is to completely replace GEOS-Chem's legacy emissions routines with a modern emissions package that can be easily interfaced to an external GCM. Many modifications to facilitate the GEOS-Chem/GEOS-5 interface were standardized in GEOS-Chem v9-01-03.
Read emission data at native resolution and regrid on the fly	GEOS-Chem Support Team	This has more or less been achieved with the addition of the these packages: MAP_A2A regridding algorithm (v9-01-03k) New Olson land map module (v9-01-03i) New MODIS LAI module (v9-01-03j) Also note: the new Grid-Independent Emissions Component will also perform this functionality by taking advantage of the regridding features of the Earth System Model Framework. This is an ongoing development project.
Improved atmospheric-ocean-land coupling of Hg simulation	Hg and POPs Working Group
Primary biological aerosol particles (PBAP's)	Colette Heald (Colo. State)	Only to be implemented if users identified
Effective meteorolgical fields for dust and sea-salt emissions	GEOS-Chem Support Team
Dust simulation expansion; tagged simulation, oxalate, Fe, P	Matthew Johnson (NCSU)	Matthew Johnson wrote: I am presently working on publishing this work and this is my last step before graduating with PhD. I will have little time to work on getting this code ready for full implementation. This is due to the fact I have my code in an older version of the model and the newer versions of GEOS-Chem do not even use the same chemical solver and aerosol thermodynamics solver. So it would be alot of work to get the model ready right now.
Benchmark for aerosol deposition	Colette Heald (Colo. State)	TBD

--Melissa Payer 12:23, 19 September 2012 (EDT)