METHODS: In collaboration with the NAB of the AAAAI, we assembled a database of speciated daily pollen counts from 51 stations across the US including data from 2003 to 2016 inclusive. We analyzed pollen season parameters by station, latitude, and ecological zone; examined bivariate correlations between temperature and total and speciated pollen season parameters; and assessed trends in pollen season parameters over the study period.
RESULTS: Data covered most of the US with some gaps in the Midwest and Southwest. Highly allergenic genera dominated counts throughout. Within genera, seasonal parameters varied by latitude and ecological zone, with onset occurring 1-2 months earlier in southern latitudes. Season peaks followed onsets by a consistent lag, with slightly longer seasons in southern latitudes. Ulmus distributions were unimodal in northern latitudes and bimodal in southern areas. Spring temperatures were highly correlated season onset, exhibiting Pearson correlation coefficients ≥ 0.6 for over half of the sample. Over the study period, certain genera demonstrated earlier onset and increased duration, particularly in northern latitudes.
CONCLUSIONS: Allergenic pollens show consistent patterns modified by latitude and ecological zone; these local distributions can be used to help guide medical management. Our findings suggest strong potential for predictive modeling of allergenic pollen season parameters. Trends over time suggest a potential association with shifting temperatures for some genera.