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

Abstract

A fundamental aspect of climate change is the potential shifts in flowering phenology and pollen initiation associated with milder winters and warmer seasonal air temperature. Earlier floral anthesis has been suggested, in turn, to have a role in human disease by increasing time of exposure to pollen that causes allergic rhinitis and related asthma. However, earlier floral initiation does not necessarily alter the temporal duration of the pollen season, and, to date, no consistent continental trend in pollen season length has been demonstrated. Here we report that duration of the ragweed (Ambrosia spp.) pollen season has been increasing in recent decades as a function of latitude in North America. 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. Overall, these data indicate 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. This is consistent with recent Intergovernmental Panel on Climate Change projections regarding enhanced warming as a function of latitude. If similar warming trends accompany long-term climate change, greater exposure times to seasonal allergens may occur with subsequent effects on public health. aerobiology | allergies | global warming

The influence of extreme high and low temperatures and precipitation totals on pollen seasons of Ambrosia, Poaceae and Populus in Szeged, southern Hungary

“…A moderate warming is favourable for Ambrosia (Ziska et al, 2011). The increase of the mean temperature for the warm-tolerant Ambrosia, especially in summer time (August), can restrict its ability to pollinate, since the plant concentrates on preserving water and maintaining its vegetative life functions rather than its generative functions.…”

“…cold or hot days, as well as droughts or rainy periods) can be persistent and can keep up to several weeks and even they can be repeated several times. Global warming may facilitate the extension of certain herbaceous and arboreal plant habitats by contributing to the increase of pollen levels and to the exacerbation of their adverse effects, hence to the rise of pollen sensitivity and respiratory admissions due to a pollen allergy (d 'Amato & Cecchi, 2008;Ariano et al, 2010;Ziska et al, 2011). Thus, the analysis of the effects of long-lasting extreme weather events on the daily or annual pollen concentrations is of ever increasing importance.…”

Aerobiology in the International Journal of Biometeorology, 1957–2017

“…As noteworthy as the IJB contribution to this area of research has been, it has not been the sole domain of such work. For instance, Ziska et al (2011) published an impactful study in the Proceedings of the National Academy of Sciences of the United States of America showing recent warming was associated with increased length of the ragweed pollen season in central North America.…”

Global Climate Change and Children’s Health

“…Air quality can be reduced through temperatureassociated elevations in ground-level ozone concentration, 32 increased pollen counts and allergy season duration, 33,34 and wildfire smoke 35 ; all of these factors exacerbate respiratory disease and asthma in children. Climate influences the behavior, development, and mortality of a wide range of living organisms, 36,37 some of which have the potential to cause pediatric infection.…”