Mar 8, 2011

Recent warming by latitude associated with increased length of ragweed pollen season in central North America

Ziska, L, Knowlton, K, Rogers, C, Dalan, D, Tierney, N, Elder, M, Filley, W, Shropshire, J, LFord, L.B., Hedberg, C., Fleetwood, P., Hovanky, K.T., Kavanaugh, T., Fulford, G., Vrtis, R.F., Patz, J., Coates, F., Bielory, L., Frenz, D.
Proceedings of the National Academy of Sciences
  • Reports that duration of the ragweed (Ambrosia spp.) pollen season has been increasing in recent decades as a function of latitude in North America
  • Finds that latitudinal effects on increasing season length were associated primarily with a delay in first frost of the fall season and lengthening of the frost free period
  • Indicates a significant increase in the length of the ragweed pollen season by as much as 13–27 d at latitudes above ~44°N since 1995
  • States that the findings are consistent with recent Intergovernmental Panel on Climate Change projections regarding enhanced warming as a function of latitude