Climate Change
Runny noses, itchy eyes, and worsening asthma are more than just seasonal nuisances—experts warn they are symptoms of an expanding public health crisis fueled by climate change. The frequency and severity of hay fever and other allergies are increasing dramatically, driven by rising global temperatures and elevated levels of carbon dioxide.
The United Nations’ World Meteorological Organization (WMO) has confirmed that climate change is significantly altering pollen production and distribution patterns worldwide.
Warmer springs and earlier thaws are prompting trees and plants to bloom much earlier than in the past, effectively lengthening pollen seasons. Meanwhile, increased CO₂ levels—produced largely by the burning of fossil fuels—enhance plant growth and lead to greater pollen production. This means more allergens in the air for longer periods, directly affecting respiratory health, particularly in industrialized nations.
Adding to the issue, air pollution is not just affecting human lungs. It also stresses plants, causing them to release more allergenic and irritant pollen. According to a 2023 WMO report, this phenomenon is already making allergy symptoms more widespread and more severe. The spread of invasive species like ragweed—an extremely allergenic plant—is another factor intensifying the problem.
Hotter, drier summers are ideal for ragweed proliferation, especially in parts of Europe. A 2017 study projected that the number of Europeans affected by ragweed allergies could increase from 33 million to 77 million by 2060 due to climate change.
In response, initiatives across Europe are trying to mitigate these effects. The “AutoPollen” program is being developed to provide real-time data on the distribution of pollen and fungal spores.
Switzerland has teamed up with MeteoSwiss to match individual allergy profiles with regional pollen maps, while in France, “pollinariums” are being planted—gardens filled with allergenic plants that allow authorities to alert residents when pollen levels begin to rise. This helps allergy sufferers begin protective treatments like antihistamines in advance.
Japan is going further by taking a more aggressive approach. In 2023, its government announced a plan to combat cedar tree-related allergies by replacing the highly allergenic trees with species that produce less pollen.
European countries are similarly reevaluating which trees are planted in public spaces. While complete elimination of allergenic species is not the goal, efforts are being made to diversify urban greenery and avoid monocultures—such as rows of birch trees—that can exacerbate allergy symptoms.
Botanist Salome Pasquet, who works with the French pollen garden initiative, notes that flowering now begins earlier than ever. “Hazelnuts have started to bloom as early as mid-December due to increasingly mild winters,” she said.
For allergy sufferers like Simon Barthelemy, an architect near Paris, the impact is deeply personal. His allergy symptoms—triggered by birch trees in a neighbor’s yard—have become a yearly struggle. “If I don’t take antihistamines, I get itchy eyes, constant coughing, fatigue, and I can’t sleep,” he explained.
As global warming continues unchecked, the burden on individuals and healthcare systems is likely to increase. Experts say we are entering an era where climate change isn’t just a planetary concern—it’s a daily health hazard for millions.
