Will hailstorms be more common on the Canadian Prairies in the future? That question was posed by atmospheric scientists from Environment and Climate Change Canada and the University of Manitoba in a recent article titled “The changing hail threat over North America in response to anthropogenic change” in the journal Nature Climate Change.
Disclosure: I was involved in writing some of the code used for the data analysis in this study (see article acknowledgements). However, I was not an author of this publication and the opinions below are my own.
This study examined changes in hail across North America using three climate models that simulated future conditions between 2041 and 2070. The model was used to study changes in hail size, frequency, and seasonality. Interestingly, there was not a single uniform trend in hail across all of North America. Some parts of North America, like the southeastern United States, appear likely to see less hail due to higher freezing levels in the atmosphere. Higher freezing levels cause hail to melt before hitting the ground, reducing the size of hail stones, or eliminating them completely. Other parts of North America, like the front range of the Rocky Mountains, will probably see more hail. However, for large parts of the continent, the study found no clear trend in the number of future hail events.
Another aspect of the study examined how hail size will change in the future. In the spring, the study showed most of North America receiving larger hail, but in summer some parts of the continent will likely see larger hail, while other parts see smaller hail. This is again due to increases in temperature in some regions, which will cause hail to melt more before hitting the ground.The last aspect of the study looked at whether the peak in hail season will change. In most of Canada peak hail season is June or July.This isn’t expected to change much on the Prairies, but in eastern Canada there does appear to be a slight trend towards an earlier peak in the hail season.This study is quite interesting, because it’s one of the first to look specifically at how hail will change in the future. Many past studies have just examined at how severe weather in general will change, but didn’t examine the specific impacts. While this study provides good insights into future hail trends, I’ll just add one caveat; this is only one study based on three model simulations. In science it’s important to have as much corroboration as possible for your findings. For that reason, I wouldn’t put all my proverbial eggs into this one study’s basket. I expect that we’ll see more hail studies in the future that can be compared to this article. Once we see additional research on this topic, we can determine whether we’re seeing the same trends in all the various studies, or if there is still uncertainty in future hail trends.