Dear PO.DAAC Users,
The PO.DAAC is happy to announce the release of the Cross-Calibrated Multi-Platform (CCMP) Ocean Surface Wind Components (Atlas et al. 2008, 2009). This product is a multi-satellite climate data record (CDR) for ocean surface wind that spans nearly 21 years. The product is derived through cross-calibration and assimilation of ocean surface wind data from SSM/I, TMI, AMSR-E, SeaWinds on QuikSCAT, and SeaWinds on ADEOS-II. Cross-calibration is performed by Remote Sensing Systems (RSS) under the DISCOVER project (http://www.remss.com/). These data sets are combined with conventional observations and a starting estimate of the wind field using a variational analysis method (VAM). The ECMWF Reanalysis (ERA-40) is used as the starting estimate (or background) for July 1987 until December 1998 and the ECMWF Operational Analysis is used from January 1999 onward.
CCMP consists of three unique data sets, each of which is stored on a uniform grid with a resolution of 0.25°x0.25°. The principal data set, denoted Level 3.0, contains gap-free wind vector analyses every six hours (initialized at 00 GMT) in its near global (78.375°S to 78.375°N) domain. These analyses are also time averaged over 5-day and monthly periods to derive the Level 3.5 data sets. For level 3.5a data sets, only those grid points with one or more analyzed observations are used in the averages to more accurately approximate a satellite-only climatology. A level 3.5b data set, which shall make use of all analysis points, will soon be available. Finally, directions from the VAM analyses are assigned to the wind speed observations for each passive microwave sensor to derive the Level 2.5 data sets. Level 2.5 data is available in a binary Bytemap format to parallel the original satellite data files from Remote Sensing Systems.
CCMP is the culmination of nearly a decade of work beginning with NASA's SSM/I Pathfinder program, which led to the production of the SSM/I Derived Ocean Surface Wind Components dataset (Atlas et al. 1996). The success of this project led to more funding through REASoN to begin work on multi-satellite data assimilation from SSM/I, TMI, AMSR-E, SeaWinds on QuikSCAT, and SeaWinds on ADEOS-II. NASA's Making Earth Science data records for Use in Research Environments (MEaSUREs) program is currently funding the CCMP project to extend its CDR time series to 2012. The current series of CCMP products is known as First-Look (FLK). Late-Look (LLK) products are to be delivered shortly after the completion of the expected 25-year CCMP time series. The CCMP project aims include additional cross-calibrated data sets (such as Windsat and NSCAT) as well as other enhancements.
In addition to having been evaluated by some members of NASA's Ocean Vector Winds Science Team (OVWST), PO.DAAC's exclusive "Product Preview" allowed for the opportunity for all users to evaluate the CCMP product for a full year before its approved public release on May 11, 2009.
To learn more and access the CCMP datasets, please visit our web portal: http://podaac.jpl.nasa.gov/DATA_CATALOG/ccmpinfo.html.
Disclaimer: All CCMP datasets represent an "analysis" (as opposed to an observation), which is a result of a combined assimilation and cross-calibration of instrument measurements and numerically-derived analyses from ECMWF. For more information on how these products were derived, as well as known problems, please download the user guide (please note that the user guide may be updated periodically): ftp://podaac.jpl.nasa.gov/ocean_wind/ccmp/L3.0/doc/ccmp_users_guide.pdf. Additional details may be obtained from the references cited in the user guide.
If you have any comments or questions, please email us at podaac@podaac.jpl.nasa.gov.
Respectfully,
PO.DAAC User Services
Citations:
[1] Atlas, R., R.N. Hoffman, S.C. Bloom, J.C. Jusem, and J. Ardizzone, 1996: A multiyear global surface wind velocity dataset using SSM/I wind observations. BAMS, 77, 5, 869-882.
[2] Atlas R., Ardizzone J., Hoffman R.N., 2008: Application of satellite surface wind data to ocean wind analysis, Proc. SPIE, Vol. 7087, 70870B (2008); DOI:10.1117/12.795371.
[3] Atlas R., Hoffman R. N., Ardizzone J., Leidner S. M., Jusem J. C., 2009: Development of a new cross-calibrated, multi-platform (CCMP) ocean surface wind product. AMS 13th Conference on Integrated Observing and Assimilation Systems for Atmosphere, Oceans, and Land Surface (IOAS-AOLS)
--------------------------------------------------------------------
User Services Office
Physical Oceanography DAAC Email: podaac@podaac.jpl.nasa.gov
Jet Propulsion Laboratory WWW URL: http://podaac.jpl.nasa.gov
News:
-Find answers using our new FAQ tool
(http://podaac.jpl.nasa.gov/HELP/index.html)
--------------------------------------------------------------------
To be removed from the GENERAL list, click here
or send an email to podaac@podaac.jpl.nasa.gov with your request.