By 2050, one in every three Americans will be exposed to extreme climate events every year, according to a study led by the Oak Ridge National Laboratory (ORNL). The researchers used the Titan supercomputer to estimate the frequency of nine types of extreme climate events, ranging from heat waves to intense floods.
The projections are based on the National Oceanic and Atmospheric Administration’s National Centers for Environmental Information Climate Extremes Index, or CEI.
The findings indicate that extreme weather will increasingly threaten human health, ecosystem stability, and regional economies over the next three decades.
Previous research has been primarily focused on the potential impacts of a single type of weather extreme, such as temperatures or precipitation, on broad climate zones.
The ORNL study has quantified the consequences of coninciding weather extremes on a county level, generating unprecedented regional and climate projections that can pinpoint the areas that will be hit the hardest.
“We calculated population exposure at a one-kilometer scale, which had never been done before, to provide more precise estimates,” explained Moetasim Ashfaq, a climate computational scientist at ORNL.
According to the study, more than 47 million people in the United States are currently exposed to extreme climate conditions each year – a number which has gradually increased in recent decades. The research suggests that this number will double by the year 2050, when one in every three residents of the United States will be directly affected by extreme climate events on an annual basis.
Human health, food security, and ecosystems will widely suffer from the impacts.
The researchers determined that human-induced climate change is to blame for the projected increase in extreme weather, and widespread exposure is highly likely within 30 years unless harmful greenhouse gas emissions are reduced.
“Seeing the same upward trend in the number of climate extremes in our historical simulations and observations strongly suggests that these changes are driven by human activity,” said Ashfaq said.
The experts will run another set of simulations based on new scenarios for the next Intergovernmental Panel on Climate Change (IPCC) report, and their findings have already been incorporated into additional studies.
“These collaborative efforts could uncover how various climate extremes affect certain areas and help determine the types of policies and mitigation strategies that may be required to prevent or reduce the damage,” said Ashfaq.
The study is published in the journal Earth’s Future.