Will Climate Change Make Pollen Allergies in South Florida Worse?

As South Florida experiences rising temperatures due to ongoing climate change, many residents might wonder how this will impact pollen allergies. Pollen from trees, including oaks and pines, is a major trigger for allergy symptoms, especially when it accumulates on surfaces like windshields and streets. Traditionally, studies suggest that warmer temperatures lead to increased pollen production and longer allergy seasons across the United States, based on data spanning over two decades. However, South Florida's subtropical climate complicates this trend.

In subtropical regions like South Florida, where temperatures are often hot year-round, the effect of climate change on pollen is less straightforward. For instance, while some research indicates that rising temperatures up to a certain point encourage earlier and more prolonged pollen seasons, extremely high temperatures—specifically above 90 to 95°F—may suppress pollen production altogether. This is because overly hot days can inhibit the flowering process of plants.

A study analyzing data over 28 years from various U.S. locations found that, generally, increasing temperatures and elevated levels of carbon dioxide have led to higher pollen concentrations. Nonetheless, in South Florida, other factors such as drought conditions, prior cold spells, and consistent warmth influence pollen levels significantly. Dr. Marc Frank, a botanist at the University of Florida, explains that conditions vary yearly and are influenced by multiple environmental variables.

Unlike most parts of the country, where plants produce most pollen in spring, South Florida's flora tends to bloom throughout the year, making allergy seasons persistent rather than seasonal. Interestingly, data from the U.S. National Phenology Network indicates that in 2024, while spring arrived earlier in the central U.S., timing in South Florida was different—spring arrived late in the northern peninsula and showed little change in the south.

Looking ahead, extreme heat days could actually reduce pollen production in South Florida. If the region experiences more days with temperatures exceeding 90°F earlier in the year, it may lead to a decrease in overall pollen levels and potentially shorten allergy seasons. Therefore, while climate change is influencing pollen patterns, its effects in South Florida are complex and not solely characterized by increased allergy risks.

Overall, residents should stay informed and prepared, but the relationship between climate change and pollen allergies in South Florida involves a mix of factors that can both increase and suppress pollen levels, making it essential to consider local environmental conditions.

Source: https://medicalxpress.com/news/2025-04-pollen-allergies-worse-south-florida.html