Cape Breton Weather
er 353! What a vivid way of depicting the variation in daily precipitation amounts!
Naturally, I wondered about Cape Breton’s 50% day numbers. I dove into Sydney’s daily precipitation for the years of 2012 through 2018 and found the average 50% day was 24. This relatively high value indicates that Sydney’s precipitation is distributed more evenly than at many other places. Cape Breton’s location on several major storm tracks and its rugged topography combine to bring us precipitation on most days of the year: 191 of them on the average. In contrast, a few rainy days in a semi-arid place like Saskatoon can dominate its annual precipitation picture. Saskatoon’s 50% day number last year was only 13, barely half of Sydney’s.
Somehow every weather article, no matter where it begins, seems to end up with climate change, and this one is no exception. Pendergrass and Knutti used computer-based climate models to study how the 50% day number might change from now until the end of the century. The models projected a slight decrease, from day 12 to day 11. In other words, in future years, the eleven wettest days will produce as much precipitation as the 12 wettest days do now. Concentrating the precipitation into fewer days implies a heightened risk for future heavy downpours and flooding.