The Canadian programme of experimental measurement of sea-state characteristics by sky-wave radar

In June, 1980, a limited programs of sky-wave radar measurements was undertaken to investigate the feasibility of measuring sea-state characteristics off the coast of Newfoundland. The program involved the collection of data by the Communications Research Centre's (CRC) Sampled Aperture Receiving Array (SARA) facility at Ottawa, the compilation of ground-truth maps of wave height, wind velocity and ice coverage by the Centre for Cold-Ocean Resources Engineering (C-CORE) in Newfoundland, and data analysis and interpretation by both agencies. A number of day-time experimental runs were made between October, 1980, and April, 1982. Because it was felt that ionospheric disturbances would preclude the recording of useful results, runs were made, as much as possible, only during periods of relatively quiet ionospheric conditions. As was expected from the earlier experience of U.S. workers, maps of wind direction usually could be derived from the data, but maps of wave heights were quite sparse: less than one-quarter of the data were useful. In fact, since the acceptance criterion developed by the U.S. workers was found to reject virtually all of the Canadian data; a manual acceptance technique had to be employed. While this technique has made possible the recovery of experimental results, it would be impractical in an operational radar. Determination of other sea-state characteristics, such as sea-wave spectra, the magnitude of the swell component or independent measurement of wind speed, was not possible from the data collected.