If you’ve been sneezing more, rubbing your itchy eyes, or popping antihistamines like candy, you’re not alone—and it’s not just your imagination. Climate change is making hay fever worse, and the data now proves it.
A new comprehensive review in The Laryngoscope confirms what allergy sufferers have long suspected: warmer temperatures, higher carbon dioxide levels, and shifting weather patterns are supercharging pollen seasons across the globe. Spring allergies are arriving earlier, lasting longer, and hitting harder.
“Allergic rhinitis used to be seasonal. Now, it’s practically year-round for some people,” says Alisha Pershad, a medical student at George Washington University and lead author of the new study.
What the Science Says
Pershad and her team reviewed 23 years of research to uncover the relationship between climate change and allergic rhinitis (AR). Out of all studies published between 2000 and 2023, only 30 met strict criteria focusing on climatological mechanisms directly influencing allergy seasons.
Their findings? Stark and sobering:
- Over 50% of the studies reported either longer pollen seasons, higher pollen concentrations—or both.
- Some projections estimate a 16% to 40% rise in pollen emissions in the U.S. by 2100, with allergy seasons lengthening by an additional 19 days.
- A 2021 study in Australia directly linked higher CO₂ levels and rising temperatures with increased grass pollen levels between 2016 and 2020.
- European projections predict a near doubling in ragweed allergy sufferers—from 33 million to 77 million—between 2041 and 2060.
In short, climate change isn’t just turning up the global thermostat—it’s weaponizing nature against our immune systems.
Why This Is Happening
The biological connection is clear: plants grow more, and produce more pollen, in warmer and more carbon-rich environments. Higher humidity and CO₂ levels amplify pollen production and dispersal. On the flip side, heavy rainfall temporarily reduces airborne allergens—but it can also fuel mold growth, another potent allergen.
One study even found that Aspergillus mold thrives under today’s CO₂ levels more than it did during the pre-industrial era.
Not Everyone Suffers Equally
Hay fever is also a story of inequality. Race, income, age, and geography all influence how severely people are affected. Communities of color, low-income households, and children are disproportionately impacted, largely due to systemic environmental injustices and infrastructure gaps.
“Communities affected by redlining tend to live in hotter regions,” Pershad notes. “And lower-income homes often can’t fix water damage quickly enough to prevent mold.”
Urban areas, despite having fewer plants, also worsen allergies through the urban heat island effect, where concrete traps heat, intensifying pollen levels.
Doctors Are Taking Notice
Physicians on the frontlines are sounding the alarm. A 2022 survey of pulmonologists in Italy revealed:
- 56% observed earlier and longer allergy seasons,
- 45% saw more AR cases overall,
- And 61% noted increased cases among children.
An overwhelming 97% of doctors want to learn more about how climate change is reshaping allergic diseases.
“Physicians have a unique platform,” says Pershad. “They’re trusted, they’re informed, and they see the damage firsthand. They should be leading the charge for climate action.”
What Can You Do?
While global climate policy is essential, individuals can take steps to minimize allergy exposure:
- Track pollen forecasts and limit outdoor activity on high-count days.
- Use air purifiers and keep windows closed during peak season.
- Consult your doctor about allergy management, especially if symptoms worsen.
But ultimately, this is a public health crisis tied to a planetary emergency.
Allergy season isn’t just a nuisance anymore—it’s a warning. Climate change is in the air, and for millions, it’s harder to breathe.