New research showing how global warming intensifies extreme rainfall at the regional level could help communities better prepare for storms that in the decades ahead threaten to swamp cities and farms.

The likelihood of intense storms is rising rapidly in North America, and the study, published Monday in theProceedings of the National Academy of Sciences, projects big increases in such deluges.

“The longer you have the warming, the stronger the signal gets, and the more you can separate it from random natural variability,” said co-author Megan Kirchmeier-Young, a climate scientist with Environment Canada.