Allergy season hits Nashville

You're not imagining things: Allergy season in Nashville increased by 25 days on average between 1970 and 2021, per an analysis from the nonprofit news organization Climate Central.

• That's based on the number of days between the last freeze each spring and the first freeze each fall — essentially, the annual window during which seasonal allergy sufferers are most likely to rely on their antihistamine of choice to get by.

Why it matters: The lengthening allergy season — which is tied to climate change, per Climate Central — has big health ramifications for the roughly one in four Americans who suffer from seasonal allergies.

• Longer stretches without freezes give plants more time to flower and release irritating pollen, per Climate Central.
• From 1990 to 2018, pollen counts increased by 21% nationwide, according to a 2021 study, Axios' Arielle Dreher reports.

What he's saying: "Across the country, allergy seasons are getting longer because of the fact that our winters are getting shorter," Stokes Peebles, professor of medicine and section chief for allergy and immunology at Vanderbilt University Medical Center, tells Axios.

• Peebles says year-to-year trends in Nashville can vary widely based on specific weather patterns that promote pollen production.

Flashback: A stretch of unseasonably warm and wet weather earlier this year created a tough dynamic for people with allergies.

• But frost last month might have inhibited pollen production.

The big picture: Peebles says some of his patients have severe allergies that can be debilitating. They can also exacerbate the impact of asthma and other respiratory diseases.

What's next: Ongoing climate change means further deviation from what was once considered the norm.

• "We do expect that areas that haven't previously had substantial pollen seasons will potentially start to experience pollen seasons," William Anderegg, director of the Wilkes Center for Climate Science & Policy at the University of Utah, tells Axios.