Washington, D.C. – As the spring season unfolds in Washington, D.C., tree pollen emerges as a microscopic yet potent culprit that plagues allergy sufferers. This year, the region has experienced abnormally warm temperatures, leading to record-high levels of tree pollen. The pollen counts have soared into the high range on multiple days, with the peak daily count reaching 1,171 pollen grains per cubic meter of air in early March.
The early arrival of spring has been marked by Washington’s sixth-warmest average temperature on record. The rapid transition of plant and tree life, including the iconic cherry blossoms at the Tidal Basin, signifies the acceleration of the season. This trend of early spring onset and heightened allergy season has become increasingly common due to rising temperatures attributed to human-induced climate change.
Experts have observed an early start to the tree pollen season in 2024, with counts rising above average levels since late January. Despite brief disruptions during cold spells, the pollen season has intensified during late winter, following a pattern seen in recent years. Moderate tree pollen levels were detected earlier than usual, with high-pollen days occurring sooner than expected.
Susan Kosisky, the director of aerobiological reporting and evaluation at the U.S. Army Centralized Allergen Extract Lab, noted a significant increase in pollen levels during the fourth week of February. The region also experienced the second-highest average pollen counts on record in late February and early March. Although the count has yet to surpass 1,500 grains, experts anticipate a continued rise in levels as the season progresses.
The spike in tree pollen is closely linked to the unseasonably warm winter and early spring temperatures. With fewer overnight freezes and consistently higher temperatures than normal, trees have been triggered to release pollen earlier than usual. This trend aligns with the overall increase in Washington’s average temperature, with temperatures rising steadily over the decades.
Studies have shown a direct correlation between rising temperatures, increased carbon dioxide levels, and heightened pollen levels. Climate change has led to an expansion of the pollen season by several weeks and a significant percentage increase in pollen production since the late 1900s. The implications of these environmental shifts are evident in the early and intense onset of the tree pollen season in Washington, D.C.
Looking ahead, experts predict the peak tree pollen season to occur around April 14 in the Washington region. Despite the early start to the season, there is uncertainty about whether the rapid onset will result in a milder second half of the season. Factors such as temperature fluctuations, humidity levels, and precipitation patterns will influence the trajectory of pollen levels in the coming weeks.
As Washington residents brace for an extended and intense tree pollen season, the interplay between climate change and allergen exposure underscores the complex relationship between environmental factors and human health. The evolving landscape of pollen production serves as a stark reminder of the far-reaching impacts of climate change on everyday experiences like seasonal allergies.