US DOE Coupled Climate Model Data Archives

Summary

Data Archives

Output data from DOE supported climate models is freely available to the climate modeling community. Currently, there are two available methods to obtain these datasets. The complete dataset is stored on the NERSC HPSS tape system, archive.nersc.gov . A NERSC user account is required to access this data via the ftp or hsi file transfer utilities. A subset of these datasets is also offered on the Live Access Server, esg.llnl.gov/las. Access to this subset is controlled by a password. As the Earth System Grid project progresses, additional technologies will be exploited.

Output results from the NCAR models, PCM and CCSM2.0 are currently available. PCM has been integrated under many different forcing configurations. Upwards of fifty different runs are available. Presently, only the control run from CCSM2.0 is available. However, the complete atmospheric and oceanic monthly datasets are available for years 350 through 999 as well as 290 years of atmospheric daily output. The data present in both of these archives has been postprocessed from the original output data. Each output variable has been extracted from the monthly history file (containing all variables for a single month or year) and written to a file containing only that variable for an extended subset of the integration time. This procedure reduces the amount of data required to construct a time series by a few orders of magnitude. Limited quality control procedures have also been applied with more QC under development. Data users are encouraged to report any problems. Users should also note that some CCSM2 data is served directly from NCAR, either via the internet or their mass storage system.

More Information

• Community Climate System Model
• Parallel Climate Model
• For questions and comments please contact:

Michael Wehner mfwehner@lbl.gov

Registering to access PCM or CCSM2.0 archived data

To access the DOE output data archives from the PCM and/or CCSM2.0, registration with NCAR is required. Ultimate permission to utilize this data is reserved by NCAR.

Step 1. Complete the NCAR web form by following the links at http://www.ccsm.ucar.edu/experiments/ . Inspect the lists of data available at NCAR to see if your needs are fulfilled. If not, proceed to the next step.

Step 2. Certain commonly accessed data is stored on the Live Access Server, http://esg.llnl.gov/las . This web interface to the data archive enables data browsing, plotting and downloading. It is especially useful for constructing subsets of a timeseries, limited either in the spatial or temporal dimensions. The PCM and CCSM2 data on this server are password protected. To get a password, fill out this form and email it to MFWehner@lbl.gov. You may browse the lists of available data without a password. If the data you are interested in is not contained on this server, or if the file sizes are very large (as is the case for variables containing height or depth dimensions), or if you need a lot of different variables from different experiments, you should get a NERSC storage account to access the tape directories by proceeding to the next step.

Step 3. The complete PCM and CCSM2 datasets are stored on the HPSS tape directory at archive.nersc.gov. To get a NERSC account, fill out this form and email it to MFWehner@lbl.gov. Clear text password ftp is not allowed on this machine. Instructions for encrypted password ftp are available here. Alternatively, the routine hsi also allows fast data transfer. Further assistance on these procedures is available by emailing consult@nersc.gov or by dialing 1-800-66NERSC (select option 3).

File structure details in the DOE climate model data archive

Many different simulations and climate variables are available. The directory structure on archive.nersc.gov is arranged in the following manner:

/nersc/mp193/mwehner/model/run_name/component_name/sampling_name/file_name

where:
model = either pcm or ccsm2.0
run_name = The NCAR assigned run name. See here and below for details.
component_name = atm, lnd, ocn or ice (atmosphere, land, ocean or sea ice).
sampling_name = mo or da (monthly or daily averaging).
file_name = A netCDF data file containing a single climate variable over the entire integration.

The monthly file naming convention is variable_name_model_run_name_start_date_end_date.nc where:
variable_name = The  climate variable name
start_date = starting date (of the form 1871.01)
end_date  = endind date (of the form 1999.12)
All monthly files begin in a January and end in a December. The time dimension is "Days since ..." A file attribute indicates whether leap years are included. Horizontal dimensions are in degrees. The atmospheric vertical dimension is model-based sigma coordinates, not pressure levels. A CDAT script to interpolate to atmospheric pressure levels is given here for PCM and here for CCSM2.0. Files from long runs may be split across the time dimension because of file size limitations. A CDAT script to create an xml spanning file in these cases is available here. (Note this is also usually the case for daily data files as well).

Currently available simulations in the DOE climate model data archive

CCSM2.0
Control Runs
b20.007
    atmospheric monthly data from years 350-999
    atmospheric daily data from years
    oceanic monthly data from years 350-999

PCM1.0
Control Runs
B04.10  (300 years)
B04.40  (20 years, all data saved on a daily schedule)

Idealized CO2 only forcings
B04.16         1.0%/yr CO2 #1 (2x @year140, CO2 capped @710ppm) 208 years
B04.29         1.0%/yr CO2 #2 (2x @year220, CO2 capped @710ppm) 111 years
B04.30         1.0%/yr CO2 #3 (2x @years270, CO2 capped @710ppm)  83 years
B04.33         1.0%/yr CO2 #4 (2x @years320, CO2 capped @710ppm)  81 years
B04.34         1.0%/yr CO2 #5 (2x @years370, CO2 capped @710ppm)  81 years
B04.19         0.5%/yr CO2 (2x @years210, CO2 capped @710ppm) 140 years
B04.23         1.0%/yr CO2 (4x @years210, CO2 capped @1420ppm) 245 years

PCM1.1
Click here for a summary table of individual forcing runs over the historical period 1890-2000.
1000+ year pre-industrial control run
B05.02 years 0070-0140
B06.18 years 0141-0388
B06.38 years 0389- 0449
B06.62 years 0450-1150

Ensemble of historical Greenhouse Gas + Sulfate aerosol (GS) forcings
B05.03         Historical 1                  1871 - 1999
B05.09         Historical 2                  1871 - 1999
B05.17         Historical 3                  1871 - 1999
B06.08         Historical 4                  1871 - 1999
B06.05         Historical 5                  1871 - 1999
B06.12         Historical 6                  1871 - 1999
B06.22         Historical 7                  1871 - 1999
B06.23         Historical 8                  1871 - 1999
B06.27         Historical 9                  1871 - 1999
B06.28         Historical 10                1871 - 1999

Future Scenario forcings
B05.12         Business-as-usual 1     2000-2099
B05.15         Business-as-usual 2     2000-2099
B05.18         Business-as-usual 3     2000-2099
B06.09         Business-as-usual 4     2000-2099
B06.06         Business-as-usual 5     2000-2099

B06.39         Business-as-usual 4a   2100-2199

B05.13         Stabilization 1      2005-2099
B05.16         Stabilization 2      2005-2099
B05.19         Stabilization 3      2005-2099
B06.10         Stabilization 4      2005-2099
B06.07         Stabilization 5      2005-2099

B06.20         IPCC scenario A2  1981-2099
B06.21         IPCC scenario B2   2001-2099

Historical GHG + SO4 + Ozone+ Solar Variability Ensemble
B05.14 Solar variability 1 1871 - 1999
B06.11 Solar variability 2 1871 - 1999
B06.16 Solar variability 3 1871 - 1999
B06.19 Solar variability 4 1871 - 1999

Historical GHG + SO4 + Ozone+ Solar Variability + Volcanoes  Ensemble
B06.57 Volcanoes 1 1870-1999
B06.59 Volcanoes 2 1870-1999
B06.60 Volcanoes 3 1870-1999
B06.61 Volcanoes 4 1870-1999

Historical Natural Forcings only (Solar + Volcanoes) Ensemble
B06.66 Natural forcings 1 1871 - 1999
B06.67 Natural forcings 2 1871 - 1999
B06.68 Natural forcings 3 1871 - 1999
B06.69 Natural forcings 4 1871 - 1999

Historical Solar Variability only Ensemble
B06.36 Solar variability only 1 1871 - 1999
B06.74 Solar variability only 2 1871 - 1999
B06.75 Solar variability only 3 1871 - 1999
B06.76 Solar variability only 4 1871 - 1999

Historical Volcanic Forcing only Ensemble
B06.77 Volcanoes only 1  1890-1999
B06.78 Volcanoes only 2  1890-1999
B06.79 Volcanoes only 3  1890-1999
B06.81 Volcanoes only 4  1890-1999

Natural + Ozone Forcing changes only Ensemble
B06.84 Solar variability only 1 1871 - 1999
B06.86 Solar variability only 2 1871 - 1999
B06.87 Solar variability only 3 1871 - 1999
B06.88 Solar variability only 4 1871 - 1999

Historical GHG + SO4 + Solar Variability + Volcanoes Ensemble (constant ozone)
B06.85 1871 - 1999