ECMWF Joint Observing System Simulation Experiment
(OSSE) Nature Run
Background and
distribution
July 2013
[Summary]
A broad group of US and international partners organized and agreed to have ECMWF compute a high resolution global gridded dataset that serves as a reference dataset for general and collaborative observing system simulation experiments (OSSE). This model output is termed ÒNature RunÓ, because it is intended to be a best representation possible of the true environmental conditions. The temporal and spatial resolution are sufficient so the data may be used as an experimental samples and validation data for planning future observing systems. It is especially valuable for assessing future satellite systems.
The description of the Nature Run is posted at
ECMWF_Joint_OSSE_NR_Data_Description.html
[Usage and credit]
This data must not be used for commercial purposes and re-distribution rights are not given. ECMWF and Joint OSSEs must be given credit in any publications in which this data is used. If you are interested in using the data set it is necessary to send E-mail with the statement below.
Please send following information to Michiko Masutani (michiko.masutani@noaa.gov).
your name,
Email address,
Affiliation,
Title of the project (or how NR will be used)
Then your name will be added to the user list and sent to ECMWF. The usage permission will be given to individual not to the institute. Therefore, everyone has to submit above information.
"I agree not to copy the ECMWF data for the use of other persons, and I
agree not to use these data and/or software for commercial purposes. ECMWF will
be given credit in any publications in which these data and/or software are
used. I understand that if other persons in my organization wish to use these
data and/or software, they must also sign a copy of this agreement."
Reference:
Andersson, E. and M. Masutani, 2010: Collaboration on
Observing System Simulation Experiments (Joint OSSE). ECMWF News Letter No. 123, Spring 2010,
14-16.
[Background]
The nature runs are used for proxy truth for Observing System Simulation Experiments (OSSE). Joint OSSE is an international collaboration. The first three nature runs, T511NR, T799NRApr06, T799NROct05 have been produced by ECMWF and verification data are also provided.
Data assessment using simulation experiments are able to provide a quantitative evaluation of future observing systems and instruments as well as existing observing systems and data assimilation systems (DAS). These experiments are known as Observing System Simulation Experiments (OSSEs). Through OSSEs, future observing systems will be designed to optimize the use of data assimilation systems and forecast models to improve weather forecasts. By using OSSEs, current operational data assimilation systems can be prepared to handle data from new sources and the operational use of data from future instruments and observing systems can be accelerated. Preparations include handling the expected volume of future data and the development of database, data processing (including formatting), and quality control systems.
The Joint Center for Satellite Data Assimilation (JCSDA), a collaboration between NOAA and NASA, recognized that it is very important that future observing systems be tested by OSSEs. Now EMC, NASA/GMAO, JCSDA, NESDIS/ORA, NASA/SIVO, NASA/ GLA, SWA, ECMWF(UK), NOAA/ESRL (Boulder ), KNMI, Environment of Canada (EC) , University of Utah, and GRI in University of Mississippi are working together to further this goal. JMA and Meteo France, JPL and the Met Office (UK) are also participating in the effort. Collectively the contributors call this the "Joint OSSEs".
The important starting component of OSSE is the nature run, which serves as ÒtruthÓ for the OSSEs. Through various previous OSSEs, it has been realized that preparation of the nature run consumes a significant amount of effort It is important to have a reference nature run so that multiple groups doing OSSEÕs can compare results. Therefore using the same nature run and extended international collaboration within the meteorological community are essential for timely and reliable OSSEs that will positively impact the design of future observing systems.
The Joint OSSE group agreed that the nature run should use a free forecast run that is forced by daily SST and sea ice, more details are available at
http://www.emc.ncep.noaa.gov/research/JointOSSEs/record/OSSE_truth.html
The complete data for T511NR and T799NR are saved at ECMWF, NCEP, NASA/GSFC, and ESRL. Model level data and surface data are saved as a reduced gaussian grid. Regular lat-lon grid data for pressure levels, isentropic levels and surface data are also provided for verification purposes.
The Nature Run is also available scientists do not have account at ECMWF,NCEP,NASA/GSFC, or ESRL . T511 NR was also saved in SWA.
Pressure level data should be used only for verification of the results and over view of the NR to decide the period of interest. It has been saved in JMA, Univ Utah, NRL(Montrey), Mississippi state Univ., Environment of Canada, NGC and JPL. Data can be send by hard disk.
[Nature Run Data at NASA/NCCS portal ]
Access to the complete data is available from the NASA/GSFC portal system:
http://portal.nccs.nasa.gov/osse
Requires a user name and password.
Contact : Ellen
Salmon (Ellen.M.Salmon@nasa.gov)
Sample line for wget script would be
wget --no-check-certificate
--user=<username> --password=<password> https://portal.nccs.nasa.gov/osse/
<path-to-file>
Please
make sure to specify "--no-check-certificate"
Technical support: Bill McHale (wmchale@nccs.nasa.gov)
Gradsdods access:
T511NR model resolution data are also available from the OPeNDAP server
http://opendap.nccs.nasa.gov:9090/dods/OSSE/T511/
please contact Arlindo da Silva (Arlindo.Dasilva@nasa.gov) for the latest location.
Gradsdods access is available for T511 NR. The data can be
down loaded in grib1, NetCDF, binary. The data can be retrieved globally or selected region.
Provide
IP number to :Arlindo da
Silva (Arlindo.Dasilva@nasa.gov)
[Nature Run Data at NCAR]
T511NR 1deg x 1deg pressure level data and cloud are saved at NCAR HPSS. The ID for the data set is ds621.0. NCAR computer account is required for access to the data.
As of January 2012 the data is posted at
http://dss.ucar.edu/datasets/ds621.0/matrix.html
More detail of the data including
corresponding NASA data is described in
ECMWF_Joint_OSSE_DATA_NCAR_NASA.html
More detail is described in
NASA_Portal_T511_reorganized.May2008.html
However, many detailed location
may have been changed. Please
contact
Ellen Salmon (Ellen.M.Salmon@nasa.gov) and
Arlindo
da Silva (Arlindo.Dasilva@nasa.gov)
For
the detail.
[Simulated
and real observation for control experiments]
Simulated observation and other data processed within Joint OSSE are also saved at NCAR HPSS. The ID for the data set is ds621.0. As of January 2012 the data is posted at
http://dss.ucar.edu/datasets/ds621.0/matrix.html
Same data with some additional data are posted from NASA/NCCS portal at
http://portal.nccs.nasa.gov/josse
More detail of the data including
corresponding NASA data is described in
ECMWF_Joint_OSSE_DATA_NCAR_NASA.html
This data must not be used for commercial purposes and redistribution rights are not given. Originating institutes must be given credit in any publications in which this data is used.
Some
evaluation of the simulated observations are included
in the presentation posted at
http://ams.confex.com/ams/92Annual/webprogram/Handout/Paper203048/JOSSE_Future_Sat.490.17in.post.pdf
[Contacts for data set]
US contact:
Michiko Masutani michiko.masutani@noaa.gov
ECMWF:
Erik Andersson
Erik.Andersson@ECMWF.int
NASA SIVO portal system:
Ellen Salmon (Ellen.M.Salmon@nasa.gov)
NASA/GSFC the OPeNDAP server
Arlindo
da Silva (Arlindo.Dasilva@nasa.gov)
NCAR: Steve Worley (worley@ucar.edu)
Chi-Fan Shih chifan@ucar.edu
[References]
Andersson, Erik
and Michiko Masutani 2010: Collaboration
on Observing System Simulation Experiments (Joint OSSE), ECMWF News Letter No.
123, Spring 2010, 14-16. http://www.ecmwf.int/publications/newsletters/pdf/123.pdf
Lahoz, William, Khattatov, Boris,
Menard, Richard (Eds.) 2010: Data
Assimilation, Making Sense of Observation.. Springer, 732 p., Hardcover ISBN: 978-3-540-74702-4
Fundamental principle of OSSE is discussed in Chapter 24.
Masutani, M., T. W. Schlatter, R. M. Errico, A. Stoffelen, E.
Andersson, W. Lahoz, J. S.. Woollen, G. D. Emmitt,L.-P. Riish¿jgaard,
S. J. Lord : Observing System Simulation Experiments
http://ams.confex.com/ams/pdfpapers/124080.pdf
. http://www.agu.org/pubs/crossref/2010/2009JD012528.shtml
Oreste et al 2007: Preliminary evaluation of the European Centre for Medium-Range Weather Forecast (ECMWF) Nature Run over the Tropical Atlantic and African Monsoon region. Conditionally accepted by Geo. Res. Letter
The list of OSSE related references are available at
http://www.emc.ncep.noaa.gov/research/JointOSSEs/references/references.html
[Related link]
Progress and meeting notes are posted at
http://www.emc.ncep.noaa.gov/research/JointOSSEs
Michiko Masutani Ph.D.
(RSIS)
NOAA/NWS/NCEP/EMC
5200 Auth Rd. Rm 207 Camp Springs MD 20746
michiko.masutani@noaa.gov
Office: (301)763-8000x7551
Cell: (240)413-6727
Fax: (301)763-8545