Benchmark/GEOS-FP 5.25

This page includes information about benchmark simulations comparing GEOS-FP 5.22.0 meteorology to GEOS-FP 5.25.1 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 New radiation scheme: The Chou-Suarez shortwave model has been replaced by RRTMG.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 raw GEOS-FP met fields downloaded from GMAO 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. If you use GEOS-FP met fields downloaded from the WashU archive then this switch starts on June 1, 2020.

The benchmark simulations below can be used to assess the impacts of this GEOS-FP system update. The simulations were completed for January 2020 using parallel streams of the GEOS-FP 5.22.0 and 5.25.1 products provided by GMAO.

NOTE: 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.

For more information about the changeover in the meteorology archive used for GEOS-Chem see GitHub issue #388. Discussion and concerns about the impacts are at Github issue #1409. A bug impacting the new dataset was discovered during development of GEOS-Chem 14.5.0 and is discussed at GitHub issue #2469.

1-month full-chemistry 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* * Lightning NOx and volcano emissions are off in both simulations because no data are available for January 2020.
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-month transport tracer benchmark plots

Species Category2	Plots
	Level Map		Zonal Mean
RnPbBeTracers Rn222, Pb210, Pb210Strat, Be7, Be7Strat, Be10, Be10Strat	sfc	500hPa	full column	stratosphere
PassiveTracers PassiveTracer, SF6Tracer, CH3ITracer, COAnthroEmis25dayTracer, COAnthroEmis50dayTracer, COUniformEmis25dayTracer, GlobEmis90dayTracer, NHEmis90dayTracer, SHEmis90dayTracer	sfc	500hPa	full column	stratosphere
WetLossConv Pb210, Pb210Strat, Be7, Be7Strat, Be10, Be10Strat	sfc	500 hPa	full column	strat
WetLossLS Pb210, Pb210Strat, Be7, Be7Strat, Be10, Be10Strat	sfc	500 hPa	full column	strat
Pb-Be Budgets	GEOS-FP 5.22.0 (Ref): Troposphere Stratosphere Troposhpere + Stratosphere		GEOS-FP 5.25.1 (Dev): Troposphere Stratosphere Troposhpere + Stratosphere
Operation budgets	Full column Troposphere Stratosphere PBL
Strat-trop exchange	GEOS-FP 5.22 (Ref): Jan 2020 values		GEOS-FP 5.25 (Dev): Jan 2020 values