More radars… not on the radar
I’ve always said that I am blessed to have so many curious followers. I receive wonderful emails with questions about the weather; those questions usually lead to a column. Having said that, today’s column was inspired by a letter that was sent to the editor; you may have read it in the Reader’s Corner on Tuesday, Dec. 4. Mr. John Wonnacott from East Jordan, N.S. (Shelburne County) wrote a very insightful letter about the lack of weather radar coverage in our region and he believes we are in need of a radar installation in the southwest region of Nova Scotia. It is true, many of the weather systems approach from the southwest and the current radar network does not extend very far offshore. The weather radar is a land-based instrument with a 250-km reach from its centre. We currently have five weather radar towers in Atlantic Canada: Chipman, near Fredericton, N.B.; Halifax; Marion Bridge (near Sydney, N.S.); Marble Mountain in western N.L.; and Holyrood near St. John’s, N.L. There is some overlap but also some gaps and, as highlighted in his letter, very little coverage just off the southwest tip of the province. Mr. Wonnacott talks about weather software that relies on radar data. In these cases, the computer interprets a lack of data as a lack of precipitation and weather maps are produced that don’t show parts of the weather system that are offshore. The maps are therefore incorrect and misleading if that is your only source. All of these points are valid, but I believe they bring us to another important issue: computer-generated products with no human intervention. Data collected and fed into a program can produce a decent product… but many times local effects or not properly considered. Getting back to Mr. Wonnacott’s point regarding offshore rain or snow, a meteorologist has other tools to help him or her identify the “part of the system” that sits offshore: Infrared and visible satellite imagery, water vapour images, vorticity charts, etc. Weather apps are very convenient and increasingly accurate, but they should not replace the detailed analyses of a trained local meteorologist. When I started to work with Environment Canada more than 30 years ago, we provided three-day public forecasts; you had to listen to the radio or watch the newscasts to get them. Today, people who rely on the weather don’t want to wait, or perhaps it’s more accurate to say they can’t wait – time is money. While I do understand that, I also believe that for a more complete understanding of a weather system and finely-tuned local details, it’s crucial to turn to a product that has been tailored or massaged by humans. Regarding the addition of a new radar in southwest Nova Scotia, the Government of Canada announced on Feb. 28, 2017 the replacement of its weather-radar network. A contract has been awarded to buy and install 20 new radars by March 31, 2023. The contract also contains options to replace the remaining radars within the same time frame. As part of this project, the radar network will be expanded by one radar, to be installed in the Lower Athabasca region in Alberta. Marion Bridge on Cape Breton Island, N.S., and Chipman radar in New Brunswick are both scheduled for replacement May to July 2019. Both are currently in the planning stages.