Rain attenuation statistics across Canada

Abstract

A method to generate rain attenuation statistics has been confirmed experimentally: actual attenuation statistics were obtained from a 5-mile microwave link operating at 11.2 GHz and compared with the results of computations from raingauge records observed alongside the link. The storm velocity required in this method was estimated from radar and from 700-mb-level wind speed. These were compared. The resulting statistics suggest that the storm velocity can be estimated from radiosonde observations where the radar facilities are not available. Using the method, 10-year attenuation statistics were computed in the regions of Halifax, Montreal, Toronto, Thunder Bay, Winnipeg and Edmonton. The statistics of attenuation for various hop lengths and various frequencies have been compiled. They are 10-year mean probabilities, year-to-year variation of the probabilities, individual duration of fade and joint and conditional probability as well as rainfall rate statistics in the regions