Climate change causes an increase in carbon dioxide, a heat trapping greenhouse gas emitted by coal, oil and other fossil fuels. When there is an increase in CO2 in the air, plants grow faster and bigger, and thus produce more pollen. Throughout the United States, pollen season has increased by 16 days since 1995, and things could get worse if the CO2 levels continue to rise.

“The link between rising carbon dioxide and pollen is pretty clear,” says Lewis Ziska, a weed ecologist at the U.S. Department of Agriculture and a top researcher in the field.

“There’s clear evidence that pollen season is lengthening and total pollen is increasing,” says George Luber, associate director for climate change at the Centers for Disease Control and Prevention. “It’s one of the ways climate change is already affecting your community.”

The CDC reported that skin allergy tests are showing increased sensitivity to ragweed, ryegrass, Bermuda grass and mold. Asthma has also seen a 17% increase since 2001, and it is very possible that asthma symptoms are being triggered by the higher pollen counts, causing people who would have gone undiagnosed to seek help for their symptoms.

In addition to pollen, experts are blaming the climate change for other allergy problems. For example, higher summertime ozone concentrations make breathing more difficult, and trigger asthma symptoms. Heavier downpours coupled with rising temperatures are fostering the growth of indoor fungi and mold, common allergens for people of all ages.

Ramie Tritt, MD, President, Atlanta ENT