Benchmark/GEOS-FP 5.25

This page includes information about benchmark simulations comparing GEOS-FP 5.22 meteorology to GEOS-FP 5.25 meteorology using GEOS-Chem 12.8.0.

Major update to GEOS-FP meteorology

NASA’s Global Modeling and Assimilation Office (GMAO) announced a major update to the GEOS-FP (“Forward-processing”) data stream. The switchover to GEOS-FP version 5.25.1 occurred on January 30, 2020. This new version contains the following updates to the GCM:

1. New convection scheme: The RAS convection scheme used to date has now been replaced with Grell & Freitas deep convection plus Park & Bretherton shallow convection.
2. New radiation scheme: The Chou-Suarez shortwave model has been replaced by RRTMG.

For more details, please read the full announcement about the update to GEOS-FP 5.25.1. Because the GEOS-FP meteorological product is an operational dataset, system changes and updates such as these are made at regular intervals. This ensures that the GEOS-FP data product reflects the state of the science. If you use GEOS-FP met fields to drive GEOS-Chem simulations for model dates after January 30, 2020, note that the convection and radiation variables might show substantial differences with respect to prior dates.

The benchmark simulations below can be used to assess the impacts of this GEOS-FP system update.

If you would prefer using a meteorology product that does not contain any system changes, then consider using the GMAO MERRA-2 reanalysis product. MERRA-2 has a native resolution of 0.5 degree x 0.625 degree native resolution, and is generated with a “frozen” assimilation system based on the GEOS GCM version 5.12.4. There are more than 30 years of assimilated MERRA-2 data available (~1980-present) for you to use with GEOS-Chem.

1-month full-chemistry benchmark

Benchmark plots

Enable PDF bookmarks¹ in the files linked below to navigate between species. See the Species in GEOS-Chem wiki page for species definitions and details.

Species Category2	Plots					Additional Information
	Level Map		Zonal Mean		Emissions
Oxidants O3, CO, OH, NOx	sfc	500hPa	full column	stratosphere	sfc
Aerosols DST1, DST2, DST3, DST4, NH4, NIT, SO4, BCPI, BCPO, OCPI, OCPO, AERI, BrSALA, BrSALC, ISALA, ISALC, NITs, SALA, SALC, SO4s, Simple_SOA, Complex_SOA	sfc	500hPa	full column	stratosphere	sfc	AOD
Bromine Bry, BrOx, Br, Br2, BrCl, BrNO2, BrNO3, BrO, CH3Br, CH2Br2, CHBr3, HOBr, HBr	sfc	500hPa	full column	stratosphere	sfc
Chlorine Cly, ClOx, Cl, ClO, Cl2, Cl2O2, ClOO, ClNO2, ClNO3, CCl4, CFCs, CH3Cl, CH2Cl2, CH3CCl3, CHCl3, HOCl, HCl, Halons, HCFCs, OClO	sfc	500hPa	full column	stratosphere	--
Iodine Iy, IxOy, I, I2, IBr, ICl, IO, IONO, IONO2, CH3I, CH2I2, CH2ICl, CH2IBr, HI, HOI, OIO	sfc	500hPa	full column	stratosphere	sfc
Nitrogen NOy, NOx, HNO2, HNO3, HNO4, MPAN, NIT, NO, NO2, NO3, N2O5, MPN, PAN, PPN, N2O, NHx, NH3, NH4, MENO3, ETNO3, IPRNO3, NPRNO3	sfc	500hPa	full column	stratosphere	sfc
Primary Organics EOH, MOH, ISOP, MTPA, MTPO, LIMO, ALK4, BENZ, CH4, C2H6, C3H8, PRPE, TOLU, XYLE	sfc	500hPa	full column	stratosphere	sfc
Secondary Organics ACTA, ALD2, CH2O, HPALDs, MACR, IEPOX, ACET, MEK, MVK, ISOPN, GLYX, HCOOH, MAP, RCHO, MP	sfc	500hPa	full column	stratosphere	sfc
Secondary Organic Aerosols TSOA0, TSOA1, TSOA2, TSOA3, ASOA1, ASOA2, ASOA3, ASOAN, TSOG0, TSOG1, TSOG2, TSOG3, ASOG1, ASOG2, ASOG3, INDIOL, LVOCOA, SOAIE, SOAGX, SOAP, SOAS	sfc	500hPa	full column	stratosphere	sfc
Sulfur SOx, DMS, OCS, SO2, SO4	sfc	500hPa	full column	stratosphere	sfc
ROy H2O2, H, H2, H2O, HO2, O1D, OH, RO2	sfc	500hPa	full column	stratosphere	--
J-values	sfc	500hPa	full column	stratosphere	--	--
Emissions by HEMCO category	Total Aircraft, Anthropogenic, Biomass Burning, Biogenic, Lightning, Natural, Ocean, Seabirds, Decaying Plants, Ship, Soil, Degassing Volcanoes, Erupting Volcanoes
Emission totals	Tables by species Tables by inventory
Global mass	Entire atmosphere Troposphere only
Metrics	OH concentration, MCF lifetime, CH4 lifetime
Budget tables	Budget totals by vertical region PBL Troposphere Stratosphere Full atmosphere

¹All plots created with GCPy have PDF bookmarks. If you do not see them in your browser try using a different browser (not Safari) or installing an Adobe Acrobat plug-in.

²Species category and lumped species definitions are simple to adjust. Updating them requires only editing the YAML files.

1-year Transport Tracers benchmarks

Three 1-year Transport Tracers benchmark simulation were performed using GEOS-Chem 12.8.0:

• GEOS-Chem Classic with the standard wet deposition scheme
• GEOS-Chem Classic with the Luo et al. (2019) wet deposition scheme
• GCHP with the standard wet deposition scheme

The GEOS-Chem Classic (w/ standard wetdep) simulation was spun up for 10 years, and the resulting restart file was used to initialize all three 1-year transport tracer benchmarks listed above.

Both GEOS-Chem Classic simulations utilized 4° x 5° GEOS-FP met fields for the year 2016. These simulations can be used to validate the Luo wet dep scheme which is offered as an option starting in this version.

The GCHP simulation used 0.25° x 0.3125° global GEOS-FP met fields for 2016 and ran at c48 resolution.

For comparison of the Pb-210 and Be-7 budgets to previous versions, please see the following posts on the Rn-Pb-Be simulation wiki page:

1. Budget of Pb210 from 1-year benchmark simulations
2. Budget of Be7 from 1-year benchmark simulations