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NAMMA TOGA Radar Data Table of Contents
This dataset consists of a collection of products derived from the NASA TOGA radar observations that were collected in the Republic of Cape Verde during the NAMMA campaign. The NASA TOGA radar is a C-band scanning radar with a beam width of 1.65º. The radar was deployed on the southern tip of São Tiago (14.92ºN, 23.48ºW), the southern-most island in the Cape Verde islands. The radar operated nearly continuously from 15 August–16 September, 2006, collecting measurements of horizontal radar reflectivity (ZH), radial velocity (VR) and spectral width (SW). Additional in-depth information can be found in namma_toga_README.pdf. These data files were generated during support of the NASA African Monsoon Multidisciplinary Analyses (NAMMA) campaign, a field research investigation sponsored by the Science Mission Directorate of the National Aeronautics and Space Administration (NASA). This mission was based in the Cape Verde Islands, 350 miles off the coast of Senegal in west Africa. Commencing in August 2006, NASA scientists employed surface observation networks and aircraft to characterize the evolution and structure of African Easterly Waves (AEWs) and Mesoscale Convective Systems over continental western Africa, and their associated impacts on regional water and energy budgets. For more information about the NAMMA Campaign, go to the NAMMA web site: http://namma.nsstc.nasa.gov/ TOGA collected 360º PPI data (no sectors or RHIs) and operated nearly continuously during NAMMA. A combination of scanning strategies was performed to achieve the TOGA radar objectives.The radar operated on a 10-minute repeat cycle, starting at the top of the UTC hour. During each 10-minute period, a 1-tilt (0.8º) surveillance scan (272 km maximum range) and one 18-21 tilt volume scan (150 km maximum range) were collected. All sampling was accomplished using a 150m bin size.The multiple tilt volume was chosen according to the existing conditions. During NAMMA, the TOGA radar documented at least six major episodes of convection (defined as significant echo within 150 km of the radar lasting at least 6 hours and exhibiting significant mesoscale organization). These features were associated with the passage of AEWs, two of which later developed into tropical storms (Debby and Helene, respectively). Movie loops:
Daily Movie loops (Quicktime format) of uncorrected radar reflectivity “dz”, corrected radar reflectivity “cz”, and radial velocity “vr”. "yymmdd" is year,month, and day. Image files:
Individual image files (png format) of uncorrected radar reflectivity “dz”, corrected radar reflectivity “cz”, and radial velocity “vr”. "yyyymmdd" is year, month, day and "tttt" is time. Gridded data files:
These are gridded data files (NETCDF format) of uncorrected radar reflectivity “DZ” and attenuation corrected radar reflectivity “CA” (i.e.,the best estimate of radar reflectivity)”. These files were generated using the NCAR REORDER software and consist of interpolated data in a 200 x 200 km box surrounding the TOGA radar site. The grid extends from 1.5 to 20 km in the vertical. The 3 km grid spacing was chosen to approximate the actual size of the beam at maximum distance from the radar in the grid (100 km). These data were interpolated using a Cressman filter and a 1.5 km radius of influence. "yymmdd" is year, month, day and "tttt" is time. Radar data files:
These are radar data files (UF format) of unfiltered radar reflectivity “ZT”, uncorrected radar reflectivity “DZ”, corrected radar reflectivity “CZ”, attenuation corrected reflectivity “CA”, radial velocity “VR”, and spectral width “SW”. These are the data files used (DZ and CA fields) to generate the gridded NETCDFs described above. "yymmdd" is year, month, day and "tttt" is time. The file “namma_toga_chkswp.txt” lists the time stamp (YYMMDDHHMM – UTC) and number of tilts collected for all TOGA data collected during NAMMA. This file can be used to determine which volume scan was used for a particular data and time of interest. Questions related to these data should be directed to the data provider listed below:
To order these data or for further information, please contact:
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