Alberta Hail Project Archive Project

Radar Data Format

During the Alberta Hail Project, weather radar data was recorded in a format developed for speed and space optimization on a PDP-11 and 9-track computer tapes. Today's computers and storage media would likely lead to different choices in many of the formatting decisions. While transferring the archive to CD-ROM, we have a limited opportunity to address some of these choices.

The proposed questions are intended to define the radar data archive format, and form the skeleton of the documentation to accompany the archive. Your suggestions and comments are encouraged.

• 1. Radar Calibration

     • What calibration information and documentation is necessary?

       • • for Port 1?

         • for Port 2?

         • for Port 3?

         • for Port 4?

     • Format of the files

       • • should .CLT or .DBM files be provided? What's the difference?

         • should they be in Binary or ASCII?

         • filename specification. What format do you prefer?

         • how many calibration files should be provided?

           • • representative calibration for the day?

             • all the calibrations?

     • Where should the calibration information be stored?

       • • in a single central place?

         • with every CD of radar data?

         • with each day?

         • with each file?

  2. Radar data

• • • 1. Format

      2. How is a file to be defined?

      3. A file represents one complete 3-dimensional scan by the radar, either 90 seconds for a scan to 8 degrees of elevation, or 180 seconds for a scan to 20 degrees of elevation.

      4. Time

      5. The only information stored within the file is time-of-day. The date must be obtained separately, from the filename, for example.

      6. filename specification.

      7. YYMMDDHH.mmR, where

         1. • YY - last two digits of year

            • MM - two digits for month of year

            • DD - day of month

            • HH - hour of day (24 hour clock)

            • mm - minute of first ray in file

            • R - S for S-band, C for C-band, Q for quality control

• 3. Digital radar logs

  4. Monthly digital radar logs were maintained and backed up at the end of the summer operations.

• • • • Where should the digital log information be stored?

        • • in a central place?

          • with every CD of radar data?

          • split into files to match the radar data?