University of Worcester Worcester Research and Publications

Responses to the Start of Betula (birch) Pollen Seasons to Recent Changes in Spring Temperatures Across Europe

Emberlin, Jean, Detandt, M., Gehrig, R., Jaeger, S., Nolard, N. and Rantio-Lehtimäki, A. (2002) Responses to the Start of Betula (birch) Pollen Seasons to Recent Changes in Spring Temperatures Across Europe. International Journal of Biometeorology, 46 (4). pp. 159-170. ISSN Print: 0020-7128 Online: 1432-1254

Full text not available from this repository.


A shift in the timing of birch pollen seasons is important because it is well known to be a significant aeroallergen, especially in NW Europe where it is a notable cause of hay fever and pollen-related asthma. The research reported in this paper aims to investigate temporal patterns in the start dates of Betula (birch) pollen seasons at selected sites across Europe. In particular it investigates relationships between the changes in start dates and changes in spring temperatures over approximately the last 20 years. Daily birch pollen counts were used from Kevo, Turku, London, Brussels, Zurich and Vienna, for the core period from 1982 to 1999 and, in some cases, from 1970 to 2000. The sites represent a range of biogeographical situations from just within the Arctic Circle through to North West Maritime and Continental Europe. Pollen samples were taken with Hirst-type volumetric spore traps. Weather data were obtained from the sites nearest to the pollen traps. The timing of birch pollen seasons is known to depend mostly on a non-linear balance between the winter chilling required to break dormancy, and spring temperatures. Pollen start dates and monthly mean temperatures for January through to May were compiled to 5-year running means to examine trends. The start dates for the next 10 years were calculated from regression equations for each site, on the speculative basis that the current trends would continue. The analyses show regional contrasts. Kevo shows a marked trend towards cooler springs and later starts. If this continues the mean start date will become about 6 days later over the next 10 years. Turku exhibits cyclic patterns in start dates. A current trend towards earlier starts is expected to continue until 2007, followed by another fluctuation. London, Brussels, Zurich and Vienna show very similar patterns in the trends towards earlier start dates. If the trend continues the mean start dates at these sites will advance by about 6 days over the next 10 years. Following this work, amendments will be needed to pollen calendars and local predictive models. It will also be important to assess the implications of earlier seasons for allergy sufferers.

Item Type: Article
Additional Information:

The original publication is available at

Originally deposited as National Pollen and Aerobiology Research Unit (NPARU)

Uncontrolled Discrete Keywords: birch pollen, climate change, allergy, aerobiology, aeroallergens, pollen samples, pollen seasons, NPARU
Subjects: G Geography. Anthropology. Recreation > GE Environmental Sciences
Q Science > QR Microbiology > QR180 Immunology
Divisions: College of Health, Life and Environmental Sciences > School of Science and the Environment
Related URLs:
Depositing User: Janet Davidson
Date Deposited: 28 Sep 2007 10:37
Last Modified: 17 Jun 2020 16:48

Actions (login required)

View Item View Item
Worcester Research and Publications is powered by EPrints 3 which is developed by the School of Electronics and Computer Science at the University of Southampton. More information and software credits.