United States: Pollen concentrations are anticipated to surpass historical norms in 39 states this year as rising temperatures blanket large portions of the United States, meteorologists caution.
Health specialists are advising individuals with seasonal allergies to brace for a particularly intense allergy season, which may persist well into the fall months.
“Approximately a quarter of American adults and nearly one in five children contend with seasonal allergies,” stated Alan Reppert, a senior meteorologist at AccuWeather.
“This year, millions will face heightened symptoms with prolonged discomfort in numerous regions,” he added, according to The Hill.
Reppert attributed these exacerbated conditions to the forecasted patterns of warm and wet weather, which he suggested would lead to pronounced pollen surges.
Additionally, he and fellow meteorologists referenced the notably colder and snow-laden winter experienced across much of the nation, soon to give way to significantly warmer spring temperatures.
Pollen to exceed 'historic average levels' across 39 states as hay fever sufferers given warninghttps://t.co/684EcYSTjw pic.twitter.com/2IL1npgm6v
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Brett Anderson, a senior meteorologist and climate specialist for AccuWeather, highlighted that this warming trend aligns with the patterns observed in recent years, ushering in extended growing seasons and early allergy onsets.
According to Anderson, changing climate conditions have caused allergy seasons to lengthen by one to four weeks across many parts of the country compared to five decades ago.
“Although year-to-year variations occur due to spring temperatures, storm trajectories, and added moisture from tropical storms and hurricanes, the overarching trend remains evident,” Anderson remarked.
Tree pollen, the first of the three principal allergens in the US, emerges in spring once ground temperatures climb to a consistent 40-45 degrees Fahrenheit, as per an AccuWeather analysis. This is subsequently followed by grass pollen in late spring and early summer, with weed pollen peaking in late summer and extending into fall.
“A cold start to the year in much of the eastern United States will initially suppress tree pollen levels, but brief surges of exceptionally high pollen counts are still anticipated,” Reppert explained.
Meteorologists predict the most severe tree pollen impact will be concentrated along the Gulf Coast, Central Plains, Northern Rockies, and Pacific Northwest.
AccuWeather’s findings indicate that tree pollen concentrations may exceed historical averages across a vast 2,000-mile expanse covering 22 states, as reported by The Hill.
However, Reppert pointed out that arid spring weather in the Southwest could mitigate pollen levels, offering the region a reprieve following a particularly severe onset.
Grass pollen is expected to hit the Northeast and Pacific Northwest hardest, particularly in June and July, owing to the likelihood of a warm and humid early summer.
Regarding weed pollen, meteorologists forecast a significant peak in July across the Tennessee Valley, with the potential for a secondary peak driven by increased moisture toward summer’s end.
Anderson warned that as global temperatures rise, the prevalence of lengthier and more intense allergy seasons is projected to persist over the next decade. He attributed this escalation to the continued combustion of fossil fuels, which releases carbon dioxide into the atmosphere, leading to warmer, moisture-rich air, according to The Hill.
“Increased rainfall accelerates plant growth, and higher spring temperatures paired with longer growing seasons and elevated atmospheric carbon dioxide levels contribute to heightened pollen production,” Anderson elaborated. “This phenomenon has resulted in more individuals experiencing seasonal allergy symptoms for the first time, while long-term sufferers are enduring worsening symptoms.”
