Difference between revisions of "Overview of GMAO met data products"
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=== Summary === | === Summary === | ||
+ | |||
+ | {| border=1 cellspacing=0 cellpadding=5 | ||
+ | |- | ||
+ | |''Assimilation GCM used:'' | ||
+ | |NCAR fvCCM GCM | ||
+ | |-valign="top" | ||
+ | |''Native horizontal grid:'' | ||
+ | |[http://acmg.seas.harvard.edu/geos/doc/man/appendix_2.html#A2.4 1° x 1.25°] | ||
+ | |-valign="top" | ||
+ | |''Native vertical grid:'' | ||
+ | |[http://acmg.seas.harvard.edu/geos/doc/man/appendix_3.html#A3.4 55 hybrid levels]; model top at 0.01 hPa | ||
+ | |-valign="top" | ||
+ | |''Native file format:'' | ||
+ | |HDF4-EOS | ||
+ | |-valign="top" | ||
+ | |''Temporal coverage:'' | ||
+ | |1985-2006; some 2007 | ||
+ | |-valign="top" | ||
+ | |''We regridded to:'' | ||
+ | |[http://acmg.seas.harvard.edu/geos/doc/man/appendix_2.html#A2.2 4° x 5°] at 55 sigma layers | ||
+ | |-valign="top" | ||
+ | |''Strengths:'' | ||
+ | | | ||
+ | *Long temporal horizon – 20 years of consistent met data | ||
+ | *U and V winds are 6-hr averages, not instantaneous | ||
+ | *Much better STE than any prior GEOS met fields | ||
+ | |-valign="top" | ||
+ | |''Weaknesses:'' | ||
+ | | | ||
+ | *Convection variables totally different than GEOS–3 | ||
+ | *GMAO was unhappy w/ the convection results | ||
+ | *Cloud OD’s are too low; J-values, chemistry are “too hot” | ||
+ | |} | ||
=== References === | === References === |
Revision as of 20:30, 28 July 2010
Contents
GMAO met field comparison chart
GEOS-1 | GEOS-STRAT | GEOS-3 | GEOS-4 | GEOS-5 | MERRA | |
---|---|---|---|---|---|---|
Native # of levels | 20 sigma | 26 sigma | 48 sigma | 55 hybrid | 72 hybrid | 72 hybrid |
Native grid | 2° x 2.5° | 2 x 2.5 | 1° x 1° | 1° x 1.25° | 0.5° x 0.666° | 0.5 x 0.666 and 1 x 1.25 |
Native file format | Binary | Binary | HDF4-EOS | HDF4-EOS | HDF4-EOS | HDF4-EOS |
Regridded to | 2° x 2.5° 4 x 5 |
2° x 2.5° 4° x 5° |
1° x 1° nested °2 x 2.5° 4° x 5°l |
2° x 2.5° 4° x 5° |
0.5° x 0.666° nested 2° x 2.5° 4° x 5° |
4 x 5 |
Temporal coverage | 1985 - 1995 | 1996 - 1998 | 2000 - 2002 | 1985 - 2007 | 2004 - present | 1979 - 2010 |
NOTES:
- GEOS-1 and GEOS-STRAT are now obsolete and no longer supported by GEOS-Chem
- GEOS-3 is still supported but we recommend users to migrate to GEOS-4 or GEOS-5.
- MERRA data will be made available at 4 x 5 resolution in the near future. MERRA is a long-term reanalysis done with version GEOS-5.2.0.
--Bob Y. 16:24, 27 July 2010 (EDT)
GEOS-5 and MERRA
Text to be added
GEOS-4
Summary
Assimilation GCM used: | NCAR fvCCM GCM |
Native horizontal grid: | 1° x 1.25° |
Native vertical grid: | 55 hybrid levels; model top at 0.01 hPa |
Native file format: | HDF4-EOS |
Temporal coverage: | 1985-2006; some 2007 |
We regridded to: | 4° x 5° at 55 sigma layers |
Strengths: |
|
Weaknesses: |
|
References
- Documents which describe the validation of GEOS-4 met fields in GEOS-Chem
- GEOS-4 references
- List of GEOS-4 met fields
- Availability of GEOS-4 met fields
GEOS-3
GEOS-3 was an improvement over GEOS-1 and GEOS-STRAT. However, because GEOS-3 was a pure-sigma model, there were problems in the stratosphere caused by excess noise in the winds. The GEOS-3 product was extensively used in GEOS-Chem for TRACE-P mission analysis.
Assimilation GCM used: | NASA/GSFC GEOS–3 GCM |
Native horizontal grid: | 1° x 1° |
Native vertical grid: | 48 sigma levels; model top at 0.01 hPa |
Native file format: | HDF4-EOS |
Temporal coverage: | 2000-2002 |
We regridded to: | 1° x 1° nested grids, 2° x 2.5°, 4° x 5° at 48 sigma layers |
Strengths: |
|
Weaknesses: |
|
GEOS-1 and GEOS-STRAT
GEOS-1 was the first GMAO met field data product compatible with GEOS-Chem. GEOS-STRAT was a continuation of GEOS-1, but with a finer vertical grid. Both products have been superceded by newer versions of GMAO met products and are no longer supported in GEOS-Chem.
GEOS-1 features
Assimilation GCM used: | NASA/GSFC GEOS1 GCM |
Native horizontal grid: | 2° x 2.5° |
Native vertical grid: | 20 pure-sigma layers, model top at 10 hPa |
Native file format: | NASA PHOENIX format (binary Fortran unformatted) |
Temporal coverage: | 1985-1995 |
We regridded to: | 4 x 5; 20 pure-sigma layers |
Strengths: |
|
Weaknesses: |
|
GEOS-STRAT features
Assimilation GCM used: | NASA/GSFC GEOS1 GCM |
Native horizontal grid: | 2° x 2.5° |
Native vertical grid: | 46 pure-sigma layers, model top at 0.1 hPa |
Native file format: | NASA PHOENIX format (binary Fortran unformatted) |
Temporal coverage: | 1996-1997 (some 1998) |
We regridded to: | 4 x 5; 26 pure-sigma layers |
Strengths: |
|
Weaknesses: |
|
--Bob Y. 16:43, 27 July 2010 (EDT)