March 8, 2023 -- If it seems like pollen season gets worse every year, it could be because pollen season has been growing for years, a new report says.
Climate change has caused temperatures to rise in 203 American cities since 1970, contributing to longer allergy seasons in more than 170 of them, the report by Climate Central says. Some areas of the country see first blooms weeks earlier.
The “freeze free” seasons are growing longer and more intense, the group says – and that’s bad news for the quarter of adults and fifth of children who suffer with seasonal allergies.
All seasonal allergies are being affected, experts say – springtime’s trees, summertime’s grasses, and autumn’s weeds.
"The plants can grow earlier and they can pollinate earlier. Allergies are just getting worse and worse," Kari Nadeau, MD, professor at the Harvard School of Public Health, told ABC News.
Respiratory illnesses like asthma can make pollen reactions worse.
"This is a major problem, and it will only get worse if we do not limit climate change and limit carbon dioxide production from greenhouse gases," Nadeau said.
Pollen levels now peak earlier than they used to, ABC reported, and pollen counts are higher.
Allergy season grew by an average of two weeks, the research found. Reno, NV, saw an increase of 99 days, one of the biggest. The western part of the country saw the biggest increases generally.
“Climate change will potentially lead to both higher pollen concentrations and longer pollen seasons, causing more people to suffer more health effects from pollen and other allergens,” the CDC says.