NCEP Regional Reanalysis - Status and Plans

Fedor Mesinger1, Perry Shafran1, Eugenia Kalnay2
Dusan Jovic1, Wesley Ebisuzaki3, and Coauthors

2: University of Maryland


A regional reanalysis (RR) is in progress at NCEP, aimed at creating a long-term set of consistent climate data on a regional scale, for the North American domain. The RR, or North American RR, (NARR) on its domain, will be superior to the completed NCEP/NCAR Global Reanalysis (GR), in both resolution and accuracy. This is being achieved using the GR to drive the RR system, and taking advantage of the regional Eta Model, and of the various advances that have been made in regional modeling and data assimilation since the GR system starting time of 1995. The resolution of the RR is 32 km/ 45 layers, and the domain used is the same as that of the operational Eta Model. The products archived consist of analysis and first guess fields, as well as free forecasts, to 72 h every 2.5 days. The period to be covered is 25 years, 1979-2003. Once the 25 years are completed, the RR will continue to be run in real-time, like the Ťlimate Data Assimilation System” is being run as a real-time continuation of the GR.

At the seminar, motivation for the effort, and the RR system will be summarized. The data sets used, in particular extensions compared to data used for the GR, will be reviewed. Verification and monitoring tools will be presented. A number of aspects of the results at hand at this time, for 1988, will be discussed. This will include comparisons of the RR analysis as well as first guess fields against those of the GR in terms of fits to radiosonde data, and 2 m temperature and 10 m wind comparisons against observations. Also, monthly precipitation verifications will be shown, demonstrating a very high realism of the obtained RR precipitation fields. The issues related to the real time running of the system will be summarized. Finally, output and archiving information such as lists of products saved, what projections and frequency, file sizes, and the anticipated completion times, will be presented,