NRT simulations

The Atmospheric Chemistry Modeling group at Harvard University is producing daily detailed ozone–aerosol–CO simulations with the GEOS–Chem model in support of ARCTAS. These simulations are being generated at Harvard University using the GEOS–5 assimilated data product, which are regridded from 1/2° latitude by 2/3° longitude and 72 vertical levels to a 2° latitude by 2.5° longitude horizontal resolution and 47 vertical levels. The simulations will lag the observations by only 2-3 days, and hence have been dubbed "near-real-time", or NRT for short.

Output from the NRT simulations are posted to this website and consists of 3 different kinds of quantities:

3-D timeseries data: CO, Ozone, NOx, PAN, HNO3, ACETONE, aerosols (SO4-NO3-NH4; black carbon, organic carbon, dust, sea salt)
2-D timeseries data: Tropospheric columns of O3, NO2, HCHO; Total CO columns
GEOS–Chem data saved along flight tracks: all GEOS–Chem chemical tracers absolute humidity temperature wind speed Chemically produced quantities: NO, OH, HO2 , JNO2, JO1D Aerosol optical depths

GEOS-Chem Version : v8-01-01 + minor modifications for ARCTAS mission

Met Fields : NASA GMAO GEOS-5 (version 5.1.0)

Horizontal Grid : 2 degrees lat x 2.5 degrees lon

Vertical Grid : Reduced 47 layer grid. NOTE: GEOS-5 original vertical vertical grid has 72 levels. Stratospheric levels above L=32 (176.93 hPa) are lumped in groups of 2 and 4 for computational expediency.

Tracers : 43 (NOx Ox PAN CO ALK4 ISOP HNO3 H2O2 ACET MEK ALD2 RCHO MVK MACR PMN PPN R4N2 PRPE C3H8 CH2O C2H6 N2O5 HNO4 MP DMS SO2 SO4 SO4s MSA NH3 NH4 NIT NITs BCPI OCPI BCPO OCPO DST1 DST2 DST3 DST4 SALA SALC)

NRT Start Date : Jan 1, 2008

Downloading the NRT files: You can access the NRT model files by anonymous ftp.
ftp ftp.as.harvard.edu
Name: anonymous
Password: your e-mail
cd pub/geos-chem/NRT-ARCTAS

The README file describes the files available. Note that only two users can be logged at anytime on the ftp site.

[an error occurred while processing this directive] ARCTAS: GEOS-5 Chemical Forecasts and GEOS-Chem Near Real Time Simulations
[an error occurred while processing this directive] Home GEOS-5 Forecasts NRT simulations About this interface About us ARCTAS
About the GEOS-Chem Near Real Time simulations The Atmospheric Chemistry Modeling group at Harvard University is producing daily detailed ozone–aerosol–CO simulations with the GEOS–Chem model in support of ARCTAS. These simulations are being generated at Harvard University using the GEOS–5 assimilated data product, which are regridded from 1/2° latitude by 2/3° longitude and 72 vertical levels to a 2° latitude by 2.5° longitude horizontal resolution and 47 vertical levels. The simulations will lag the observations by only 2-3 days, and hence have been dubbed "near-real-time", or NRT for short. Output from the NRT simulations are posted to this website and consists of 3 different kinds of quantities: 3-D timeseries data: CO, Ozone, NOx, PAN, HNO3, ACETONE, aerosols (SO4-NO3-NH4; black carbon, organic carbon, dust, sea salt) 2-D timeseries data: Tropospheric columns of O3, NO2, HCHO; Total CO columns GEOS–Chem data saved along flight tracks: all GEOS–Chem chemical tracers absolute humidity temperature wind speed Chemically produced quantities: NO, OH, HO2 , JNO2, JO1D Aerosol optical depths GEOS-Chem Version : v8-01-01 + minor modifications for ARCTAS mission Met Fields : NASA GMAO GEOS-5 (version 5.1.0) Horizontal Grid : 2 degrees lat x 2.5 degrees lon Vertical Grid : Reduced 47 layer grid. NOTE: GEOS-5 original vertical vertical grid has 72 levels. Stratospheric levels above L=32 (176.93 hPa) are lumped in groups of 2 and 4 for computational expediency. Tracers : 43 (NOx Ox PAN CO ALK4 ISOP HNO3 H2O2 ACET MEK ALD2 RCHO MVK MACR PMN PPN R4N2 PRPE C3H8 CH2O C2H6 N2O5 HNO4 MP DMS SO2 SO4 SO4s MSA NH3 NH4 NIT NITs BCPI OCPI BCPO OCPO DST1 DST2 DST3 DST4 SALA SALC) NRT Start Date : Jan 1, 2008 Downloading the NRT files: You can access the NRT model files by anonymous ftp. ftp ftp.as.harvard.edu Name: anonymous Password: your e-mail cd pub/geos-chem/NRT-ARCTAS The README file describes the files available. Note that only two users can be logged at anytime on the ftp site. Links NRT Simulations Status Page More info on NRT simulations Status of GMAO assimilated met fields GEOS-Chem model ARCTAS planning movies GEOS-Chem documentation GEOS-Chem faq Harvard Atmospheric Chemistry Modeling group
Send mail to: jaegle@atmos.washington.edu Last modified: 7/17/2008 11:20 AM