According to the U.S. Centers for Disease Control and Prevention (CDC), over 60 million Americans suffer from seasonal allergies caused by airborne pollen. Medical costs associated with this condition exceed $3 billion annually, and some people suffer from pollen allergies so severely that they need prescription medicine to cure their symptoms.
As an equal-opportunity irritant, pollen can cause allergies as it is blown from trees, weeds, and grasses. This powder is particularly irritating in spring and summer when it is present in high quantities. For this reason, accurate pollen forecasts are needed, which can help allergy sufferers reduce their exposure the same way that they might during high-ozone days.
Pollen-Weather Connection
For the past two years, scientists from the National Oceanic and Atmospheric Administration (NOAA)'s Global Systems Laboratory (GSL) have been working on the first pollen forecast model in the US. It was made to predict the weather's influence on pollen concentrations and how pollen loads can impact the weather.
The experimental model from NOAA has been generating pollen forecasts since the summer of 2022. It also conducts functions similar to commercial pollen forecasts, which inform the sufferers about the amount of pollen exposure they will be experiencing.
Called the Rapid-Refresh Chemistry (RAP-Chem) weather and atmospheric chemistry prediction system, the model discovered that suspended pollen particles work to scatter sunlight. As a result, this can form clouds and affect the surrounding temperature and amount of rain.
According to CIRES scientist Jordan Schnell, pollen and its associated allergies are crucial to people's daily lives. Real-time predictions of pollen and its transport can help people adjust their medications and outdoor activities and take precautionary measures to ensure their well-being.
NOAA works with public health stakeholders such as the CDC to study the connection between past RAP-Chem high pollen forecasts and allergy sufferers seeking relief. This can validate the forecast model, a necessary step in becoming an official model.
RAP-Chem Weather Model
RAP-Chem is a next-generation combined weather and air quality forecasting system that simulates gas-phase and aerosol chemistry and transport. The model makes a 48-hour forecast for air quality and atmospheric chemistry-related parameters like pollen, smoke, dust, and ozone every day.
The system works by simulating the influence of weather on pollen concentrations, such as the daily swings in airborne abundance and pollen emissions. Pollen is released during the day, mostly driven by the model's simulated winds. At night, the emissions stop, and the particles deposit to the ground, causing pollen concentrations to drop.
Rain also tends to cleanse the air and lower pollen counts. However, cold downdrafts triggered by thunderstorms can concentrate pollen particles, worsening asthma or itchy eyes. Meanwhile, humidity and lightning can break up pollen particles into tiny fragments, making them easier to reach the respiratory tract.
Unlike other existing models. RAP-Chem counts for the influence of pollen, smoke, and dust on the weather. Like other suspended particles, pollen grains can scatter sunlight and serve as seeds for cloud formation. In turn, this can affect temperature, precipitation, and visibility.
RELATED ARTICLE: Allergy Season: Allergist Alerts of Hay Fever as 'Pollen Storm' Rises Across US
Check out more news and information on Pollen in Science Times.
