Predicting Ragweed Allergy Hotspots in New England

The central objective of this experiment is to better predict the impacts of climate change on pollen-induced allergic airway disease. Specifically, we will: (1) Model pollen allergy risk factors as a function of regional climate patterns; (2) Provide ecological data on allergenic plant responses to a range of current & future seasonal conditions; and (3) Generate predictive maps of allergy “hotspots” under a range of climate change scenarios. We will evaluate the effects of environmental conditions on four pollen allergy risk factors: timing of pollen production (onset, peak and duration); pollen output; and allergic potency (allergen protein levels) in order to address the following questions: What is the role of climate on the production, distribution, dispersion and potency of pollen? How do climatic conditions affect growth, distribution and phenology of allergenic plant species? How will these risk factors change in future climate scenarios?

Approach: We will combine field sampling, geographic information system (GIS) analysis, and controlled experiments to predict when and where pollen allergies are most likely to increase in response to changes in atmospheric carbon dioxide and seasonal precipitation patterns, using the widespread hay-fever allergenic plant, common ragweed (Ambrosia artemisiifolia L.), as a model system. Field surveys will be employed to obtain population-level field data on pollen output, peak flowering times, and allergen protein. These data will be linked to national climate data using regression modeling techniques. We will conduct climate-controlled experiments to determine the range of variation among climatically distinct populations in pollen production and pollen potency in response to current and future atmospheric CO2 and precipitation scenarios. We will then incorporate our results with GIS tools to map site-specific peaks in pollen abundance, potential dispersion, and pollen potency under specific IPCC predictions for regional climate scenarios.

Expected Results (Outputs/Outcomes): This research addresses both the effects and mechanisms by which current and future climate conditions affect the risk factors related to allergic airway disease in humans. Our intensive sampling of pollen production, output, and potency in ecologically distinct ragweed populations will produce much-needed datasets on local pollen outbreaks, regional climate events, and allergenicity that cannot be captured by current National pollen counts. The expected outcomes include: greatly enhanced predictive tools and maps for forecasting allergy “hotspots” at the spatial scale that is most relevant to human exposure to pollen; demographically-relevant models of human exposure to pollen risk factors under a wide range of future climate scenarios. These research and sampling templates can be broadly adapted for other allergenic species and across different regions throughout the United States.