Characterisation of pollen seasons in Iceland based on long-term observations: 1988–2018

This paper describes a long-term (1988–2018) data series from pollen monitoring in two locations in Iceland: Akureyri and Reykjavik. Our data showed a low diversity of airborne pollen present in the aeroplankton of Iceland. We showed that Betula spp. and Poaceae can be considered the main pollen allergens in Iceland. Both Betula spp. and Poaceae pollen seasons in Iceland are characterised by a late onset compared to continental Europe. Betula spp. seasons are further characterised by a longer duration and low SPI and peak values. Icelandic Poaceae seasons are shorter, but have SPI and peak values comparable to those recorded in continental Europe. We recorded no synchronisation in the intensity of pollen production between our monitoring sites in Iceland, and our data do not confirm the existence of repeatable cycle (bi- or triennial) of high and low pollen production in Betula spp. Statistically significant trends towards increasing SPI values were recorded in Reykjavik (Betula spp.) and Akureyri (Poaceae).