The effects of patterns in climate and pollen abundance on allergy.

Recent climatic trends in Europe have been examined in the context of longer term variations and vegetation zonation. The most recent computer models of future climatic changes resulting from increasing carbon dioxide emissions are discussed in relation to the possible impacts that the predicted climatic shifts may have on the distribution and abundance of the main allergenic pollen types. The probable repercussions of these changes on the patterns and incidences of seasonal allergic rhinitis are considered. This study focuses on pollen from Betula, the Poaceae, Ambrosia, Parietaria and Olea, but also examines the implications of climatic change for other aeroallergens, including those from various crops such as Brassica species (oil-seed rape) and Helianthemum (sunflowers). In the case of natural distributions, the response of the plants to climatic changes are viewed in relation to the potential migration rates of the species. For agricultural crops, shifts in the location of productive areas involve agricultural economics both at the national and European community levels. In addition to broad regional impacts, this study examines the influence of increasing ultraviolet radiation on pollen production over various areas of Europe, and considers the effect of changing airflow trajectories on the long-range transport of pollen with pollution from central and northern Europe into Scandinavia.