Climate Corner: Climate change and your allergies

Apr 8, 2023

Rebecca Phillips

The Mid-Ohio Valley has long been known for the prevalence of respiratory woes, particularly the notorious “Ohio Valley Crud,” often a result of seasonal allergies. Unfortunately, there is bad news for allergy sufferers: Climate change is making allergy season longer and more intense, and is almost certain to continue to do so.

Researchers from Rutgers University noted in 2014 that pollen season length increased by three days just in the first decade of this century, with pollen counts rising by 40% in that same period. These phenomena are caused by rising temperatures–in other words, climate change — and increased atmospheric carbon dioxide. Warmer temperatures lead to more frost-free days, with trees blooming earlier and the first frost coming later. Our area now experiences on average nine more frost-free days than it did in 1999. Oak pollen arrives earlier, as does grass pollen. Ragweed pollen lasts longer into the fall.

Ragweed, that bane of so many people’s existence, is not just blooming longer; it is also producing more pollen. USDA scientist Lewis Ziska has found that increased CO2 levels cause ragweed plants to become larger, bloom more heavily, and therefore produce more pollen–somewhere around a billion grains per plant. Not only does it serve as fertilizer: CO2 causes the pollen to produce more of the protein that causes the allergic reaction. Not good news for us.

And the news gets worse. If current emission levels continue, some climate scientists are predicting a 200% increase in total pollen this century, with pollen seasons nearly sixty days longer in some places, particularly the northern U.S. Pollen seasons will overlap, with more varieties in the air at any given time, leading to increased exposure and increased sensitivity for allergy sufferers.

Rising temperatures and humidity are also causing increases in the growth of molds and fungi, yet more allergy triggers. The more intense thunderstorms many places are experiencing coincide with more emergency room visits for allergic asthma; some research indicates that the winds are rupturing pollen grains and allowing them to penetrate more deeply into people’s lungs. Respiratory allergies are worse in areas with compromised air quality, such as the Mid-Ohio Valley.

We joke about our “crud,” but it is no laughing matter. Nearly a third of the world’s population suffers from respiratory allergies, and the Cleveland Clinic reports recent increases in those numbers. In addition to the very real human suffering, allergic rhinitis (the medical name for the crud) has an economic impact, estimated at more than $3.4 billion in annual medical costs in the U.S. alone. Allergy sufferers miss an average of 3.6 days of work per year and are less productive at work when ill. The annual cost of asthma (not always allergy-related) is more than $80 billion, and over 4,000 Americans die from asthma attacks each year.

We can reduce this suffering and these staggering costs by reducing the carbon emissions currently serving as weed fertilizer. This valley will always have pollen season, but we do not have to keep making the situation worse.

Rebecca Phillips is a member of Mid-Ohio Valley Climate Action.