Global warming is intensifying rainstorms in North America. Rats are becoming more aggressive in their hunt for food due to pandemic lockdown measures.
If the current rate of global warming continues, North America could see 100-year rainstorms as often as every two-and-a-half years by 2100, says a new study published in the Proceedings of the National Academy of Sciences.
“We’re finding that extreme precipitation has increased over North America, and we’re finding that’s consistent with what the models are showing about the influence of human-caused warming. We have very high confidence of extreme precipitation in the future,” said study co-author Megan Kirchmeier-Young, a climate scientist with Environment Canada.
At the current level of warming caused by greenhouse gases—about 1.8 degrees Fahrenheit above the pre-industrial average—extreme rainstorms that in the past happened once every 20 years will occur every five years, according to the study. If the current rate of warming continues, Earth will heat up 5.4 degrees by 2100. Then, 20-, 50- and 100-year extreme rainstorms could happen every one-and-a-half to two-and-a-half years, the researchers concluded.
The risks will continue to increase as the atmosphere warms, said David R. Easterling, a climate extremes researcher and director of the U.S. National Climate Assessment. He warned that most current infrastructure, such as dams and bridges, was designed based on rainfall values from the mid- to late-20th century and was not built to withstand the more frequent extreme rains identified by the new research.
Restaurant closures have made rats more aggressive in their hunt for food, according to a warning from the Centers for Disease Control and Prevention.
Rats usually feast on scraps from restaurant trash bins overflowing with leftovers, but those businesses are closed or limited to takeout and delivery thanks to stay-at-home restrictions across the country. As a result, there have been increased reports of cannibalism among rats, and they’ve been moving to residential areas in search of food.
While the biggest worry comes from rodent-borne disease, experts warn that rats have also been known to devour cars. They burrow into engine compartments and gnaw at wires, insulation and even tires—which can cost a fortune to fix and has even been known to cause fires.
The CDC warning includes a list of guidelines home and business owners can follow to keep rats away from their property.