In less than a decade, scientists could point to a specific heat wave — and possibly a death toll — and blame it on climate change.
Heat waves are the deadliest type of extreme weather out there. Hurricanes are infamous for leaving a path of death and destruction, but heat waves have claimed tens of thousands of lives — and continue to do so in modern times. In 1995, a heat wave killed more than 1,000 people in Chicago. In 2010, more than 55,000 died when a heat wave sparked devastating wildfires in Russia.
New research led by scientists at the University of Miami Rosenstiel School of Marine and Atmospheric Science and NOAA shows that the future holds more heat waves in the U.S., thanks to human-caused climate change.
Without humans and their fossil-fuel-burning habits, the future would hold half as many heat waves, the research shows. And certain parts of the country could start seeing heat waves largely caused by human climate change as soon as 2027.
The research team compared two climate models — one that shows a world without human interference and another in which people burned fossil fuels and filled the atmosphere with gasses that trap heat and warm the globe. Scientists were able to pinpoint the areas in the country where heat waves that aren’t fully naturally occurring will happen first.
“It’s the first time anybody has been able to look at it on a subcontinental scale and link the patterns that occur,” said Ben Kirtman, a UM researcher on the study. “We haven’t been able to do that in the past.”
The study, published Monday in the journal Nature, used a new type of analysis to predict when heat waves driven mostly by human-caused climate change will happen.
Californians and residents of Southwestern states could see them as soon as the 2020s; for the Great Lakes, 2030; for the Northern Plains, 2050; and for the Southern Plains, 2070. The staggered time frame is due to natural weather variations that existed long before people started changing the climate.
South Florida, although notorious for high temperatures, didn’t show up in the analysis as being due for an abnormal number of heat waves in the future. That doesn’t mean the region isn’t expected to get hotter in the future. It absolutely is, Lopez said, but it’s hard to differentiate a “heat wave” when the temperatures (and humidity) are high most of the time.
“There’s no such thing as a wave here. We’re always hot,” said Hosmay Lopez, a UM meteorologist based at NOAA’s Atlantic Oceanographic Meteorological Laboratory and lead author on the study.
Lopez said he wants to take his research and try to come up with a system that predicts when heat waves will happen, potentially giving officials time to save lives. But Kirtman said the research technique Lopez pioneered could be applied to all kinds of factors, like rain and wind.
For South Florida, knowing how much extra rain is due thanks to climate change and when it’ll arrive would be critical. Particularly for the Everglades, where rain levels play a big part in calculations for restoration efforts, having an idea of how much rain to expect could be a game-changer.
“We don’t have an answer to that question,” Kirtman said.