Washington: Two of the most common allergens in the contiguous United States are oak and ragweed pollens. Researchers at the Rutgers Environmental and Occupational Health Sciences Institute have modelled how climate change may alter these two pollen distribution patterns. Your eyes may water reading the results, which were published in the journal Frontiers in Allergy.
By 2050, airborne pollen loads will significantly increase as a result of climate change, according to a team led by Panos Georgopoulos, professor of Environmental and Occupational Health and Justice at the Rutgers School of Public Health. Some of the biggest increases will occur in regions where pollen has historically been scarce. "Pollen is an excellent sentinel for the impacts of climate change because shifts in variables like carbon dioxide and temperature affect the way plants behave," said Georgopoulos, who also is director of the Computational Chemodynamics Laboratory at Rutgers and faculty at Robert Wood Johnson Medical School. "At the same time, the production of pollen and pollen's influence on allergic disease has been increasing due to climate change, and this is one of few studies to forecast this trend into the future."
Previous efforts to connect pollen indices with climate change have been limited by a scarcity of data. For instance, there are about 80 pollen sampling stations in the US, operated by a variety of private and public agencies using different sampling methods.
To overcome this challenge, the researchers adapted the Community Multiscale Air Quality modelling system, an open-source tool managed by the US Environmental Protection Agency (EPA) to simulate distributions of allergenic oak and ragweed pollen for historical (2004) and future (2047) conditions.
Results showed that even under moderate warming conditions, pollen season will start earlier and last longer throughout the US, with increasing average pollen concentrations in most parts of the nation. Mean concentrations of oak pollen could climb by more than 40 per cent in the Northeast and Southwest and mean concentrations of ragweed could jump by more than 20 per cent in these areas.
Regional pollen shifts were observed, too. In parts of Nevada and northern Texas, oak pollen levels could double by mid-century, while Massachusetts and Virginia could see an 80 per cent increase in ragweed pollen by 2050.
The pollen research was part of an ongoing project by the Rutgers Ozone Research Centre, which is funded by the EPA and New Jersey to study how climate change will influence air quality in the state. The bulk of that work examines the state's struggles with ground-level ozone, a byproduct of fossil fuel combustion that can damage the lungs.
"New Jersey's air quality is going to be adversely impacted by climate change, both in terms of anthropogenic pollution and increased levels of pollen," Georgopoulos said. "For people with asthma, exposure to pollen and irritants like ozone increases the odds of respiratory illness. To protect the most vulnerable, we need to understand how these irritants will behave in a warming world."