As climate change continues to affect ecosystems around the world, summer temperatures will likely be on the rise. It is believed that increases in precipitation could mitigate the risk of drought in some regions. While this seems like a positive outcome, a recent study published in Nature Communications has found that wetter summers may bring on other problems.
Generally, summers that are both warm and wet are unusual in most areas of the world.
“Terrestrial climates around the world tend to alternate between cool, wet summers in some years and warm, dry summers in other years,” says Colin Mahony, a University of British Columbia forestry PhD candidate and lead author of the study. “But climate change is driving many climates towards warmer and wetter conditions. We found that where temperature and precipitation are increasing together, climates are changing faster than the temperature trend alone would suggest.”
The negative impacts include disease outbreaks and crop failures, as warm and wet summers break climatic norms that ecosystems and our own communities are adapted to.
In this study, the researchers analyzed historical observations going back to 1901 and global climate model projections looking ahead to the year 2100. The results showed that subtropical and temperate regions were areas where these conditions are most likely to occur.
“We’re just getting into the time period where we expect to see this effect,” says Mahony. In the forests of western North America, recent outbreaks of fungal diseases have already been linked to warmer and wetter conditions at certain times of the year.
“Some fungal outbreaks over the past couple of decades, such as Dothistroma needle blight, could likely have been anticipated by tracking how temperature and precipitation were changing together,” explains Mahony. “In order to respond to global warming, we need to understand how the climates of the future will be different than the familiar, historical climates that we are adapted to.”