Allergy Season Lengthens Across U.S. by 3 Weeks on Average

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A new report from Climate Central reveals that allergy season has grown significantly longer across the United States since the 1970s, with the freeze-free period extending by an average of 21 days. This gives plants more time to grow and release pollen, exacerbating seasonal allergies for millions of Americans.

Why it matters

Longer allergy seasons driven by climate change can have serious health impacts, leading to increased suffering and medical costs for those with allergies. This trend also highlights the broader effects of a warming climate on ecosystems and human wellbeing.

The details

The Climate Central analysis looked at temperature data from across the country and found that the number of "freeze-free" days has increased by an average of 21 days since the 1970s. This extended growing season allows plants to bloom and release pollen for a longer period, intensifying allergy symptoms for those affected.

• The analysis examined data from the 1970s to the present day.
• Allergy season has grown by an average of 21 additional "freeze-free" days nationwide.

What’s next

Climate experts warn that as global temperatures continue to rise, allergy seasons will likely grow even longer in the coming decades, exacerbating health issues for millions.