Canadian Weather Radar Network - Scanning Strategy

Scanning Strategy

Because the network is using C band radars, compromises had to be used (see Doppler dilemma) between maximum reflectivity range and maximum non ambiguous velocities. The actual scanning strategy (2006) is divided in two separate scans over 10 minutes :

• Conventional cycle: 24 elevation angles scanned in 5 minutes to obtain a tri-dimensional view of the atmosphere within 256 km of the radar in reflectivity.
• Doppler cycle: 4 angles scanned in reflectivity and velocities, the first three in a range of 128 km and the last within 256 km. This cycle is used to locate possible small scale rotation and shear in the wind pattern as well as the large scale circulation. The velocity data also help to filter artifacts in the reflectivity such as ground echos.

Only the McGill radar (J. S. Marshall Radar Observatory) using its coherent S-band transmitter acquires reflectivities and velocities during each of its 24 elevation angles: 5 minute cycle time.

Take note that McGill. Jimmy Lake and Lac Castor radars are not owned neither operated by Environment Canada. McGill radar is operated/owned by McGill University. Jimmy Lake and Lac Castor are owned/operated by the Department of Defense (DND).