Climate change is creating a nightmare for allergy sufferers

A new study released Monday is the latest to suggest that climate change is already making people’s lives worse, this time for people with pollen allergies. The results indicate that the pollen season in North America has lengthened considerably and that pollen has become more abundant over the past three decades, in part due to a warmer climate.

There are different types of plant and tree pollen which become prevalent at different times of the year. But in general, the pollen season begins in early spring and runs through summer and early fall. These months are associated with an increase in seasonal allergies, also known as hay fever or allergic rhinitis. People with the condition experience cold-like symptoms such as a stuffy or runny nose, watery eyes, as well as itching around the nose and the roof of the mouth.

Researchers in the study looked at data from pollen counting stations across the United States and Canada, spanning 1990 to 2018. During those years, they found that the pollen season had changed dramatically. Compared to 1990, the average pollen season in an area now starts about 20 days earlier, lasts 10 days longer, and pumps 21% more pollen. While this change was seen everywhere, areas like Texas and the US Midwest experienced the greatest increases in total pollen in those years.

Some studies have found laboratory evidence that warmer temperatures should lead to a worse pollen season. Others have predicted that certain allergenic plants such as ragweed will become widespread over the next decades. But the new discoveries, published in the Proceedings of the National Academy of Sciences, is one of the first research to explicitly link climate change to worse pollen seasons, and to suggest that it makes matters worse here and now.

“Our results indicate that man-made climate change has already worsened pollen seasons in North America,” the authors wrote.

Climate change isn’t the only factor that has made the pollen season a nightmare for allergy sufferers in recent years, they noted. But according to their model, it’s likely that climate change is primarily responsible for around half of the extra days seen during that time, as well as 8% of the heavier pollen counts. They also found that climate change has had a greater contribution to the pollen season over the years, which does not bode well for what lies ahead.

“It is likely that climate change will have an even greater impact on pollen seasons and respiratory health in the near future,” study author William Anderegg, biologist at the University of Utah, told Gizmodo via email. “We saw in our study that the impacts of climate change were more pronounced over the period 2003-2018 compared to the full period 1990-2018. So, at least for the next decade or two, we really expect this trend and the health effects to continue.

Of course, a lot more pollen each year is not the only thing that climate change threatens to bring to human health. In the United States, experts fear that longer, warmer seasons increase the risk of many health problems, due to tick-borne diseases like Lyme disease at heart attacks and heat stroke to the spread of tropical diseases because warming allows them to spread to the pole.