Hourly 4´4 Precipitation Data Set for the Mississippi River Basin of the GAPP

We have developed an archival precipitation data set for the GEWEX Americas Prediction Project (GAPP). The data set spans from 1996–2000.  Inputs for the data set are the National Reflectivity Composite that we obtained in Hierarchical Data Format.  The size of the input data is 40 GB.  We have developed an efficient data format that reduces the size to 2.1 GB.  We have also developed browsing tools for users of the data set.  The data browser allows for fast and efficient viewing of the precipitation data and was produced using commercial GIS software.  In particular,  ArcView 3.2.  Supplemental data are also included in the browser as an aid to the user. 

We then implemented an estimation algorithm for precipitation estimation.  The algorithm involves investigating the quality of the input radar reflectivity data and then improving the quality of these data.  Then we determined the parameters needed for transforming reflectivity to rain rate through a Z-R relation.  Next we produced precipitation accumulations and then we investigated the data quality in the final product.  Issues related to the validation of the data set are ongoing. 

The DVD contains:

• Documentation (PDF, 1MB),
• Precipitation Data Set (2.5 GB),
•  Programmer’s Application Interface (API) to read data in C programming language, and
•  ArcView ® 3.2 Data Browser.

The data are available via a THREDDS data server, and can be accessed via any OpenDAP enabled client:

http://eclipse.ncdc.noaa.gov:9090/thredds/catalog/radar/GAPP/catalog.html

The data are available via anonymous ftp:

ftp://eclipse.ncdc.noaa.gov/pub/radar/GAPP

References

• Nelson B.R, W. F. Krajewski, J. A. Smith, E. Habib, and G. Hoogenboom, “Archival Precipitation Data Set for the Mississippi River Basin:  Evaluation,” Geophysical Research Letters, 32(L18403), doi:10.1029/2005GL023334, 2005 (Abstract).
• Nelson, B.R., W.F. Krajewski, A. Kruger, J.A. Smith, M.L. Baeck, “Archival Precipitation Data Set for the Mississippi River Basin: Development of a GIS-Based Data Browser,”  Computers & Geosciences, 29(5),595-604,  doi:10.1016/S0098-3004(03)00045-1  June 2003. (Abstract)
• Nelson, B.R., W.F. Krajewski, A. Kruger, J.A. Smith, M.L. Baeck, “Archival Precipitation Data Set for the Mississippi River Basin: Algorithm Development,” Journal of Geophysical Research, 108(D22),8857, doi:10.1029/2002JD003158, 2003. (Abstract)

Contact Information

Brian R. Nelson, W.F. Krajewski, or Anton Kruger