forecast modelling

Pollencount by hour

This graph is an example of pollenconcentration during three different types of days. Day 1 shows airborn pollen between 9:00 and 17:00. Day 2 shows a pollenpeak during the early morning hours. Day 3 shows a peak in the evening. Weatherconditions, like a rainshower, a sunny or cloudy day, have big influence on the hourly […]



About Ambrosia Ragweeds are flowering plants in the genus Ambrosia in the aster family, Asteraceae. They are distributed in the tropical and subtropical regions of the New World, especially North America, where the origin and center of diversity of the genus are in the southwestern United States and northwestern Mexico. Several species have been introduced […]


Tree calendar

This calendar shows when specific trees are flowering (in the Netherlands). The calendar is video-based. Every tree is explained by a short video. Corylus aveilana   Alnus incana   Alnus glutinosa   Salix viminalis   Taxus Bacatta   Populus x more   Carpinus Betulus   Betula pendula more information >> Fagus sylvatica   Quercus robur […]


Grass calendar

This example calendar shows when specific ¬†grasses are flowering (in the Netherlands). The calendar is video-based. Every grasstype is explained by a short video. Alopecurus pratensis Image: Alopecurus pratensis, Meadow foxtail. Five stages in ripening of the inflorescense and opening of the anthers to free pollen. more information >> Dactylis glomerata Poa pratensis Anthoxanthum odoratum […]


Winddirection and pollenpressure

Are winddirection, pollenconcentration and pollenpressure correlated? It very much depends on your location. This graph shows that for the Netherlands a south-east wind is less favourable, as it can bring pollen from Germany and Belgium. When you live on a small island like Helgaland, every winddirection is favourable. Besides winddirection also windspeed is correlated.


Windspeed and pollenconcentration

Are windspeed and pollenconcentration correlated? It seems that in periods with a low windspeed the average complainlevel is higher that during periods of high windspeed. A more detailed graph is not available yet.


Temperature and pollenconcentration

Are temperature and pollenconcentrations related? This graph shows the correlation between the average complainlevel and the temperature during two months.

clean rain

Rain and pollenconcentration

Are rain and pollenconcentrations correlated? There seems little doubt about that. Rain can wash the air clean from pollen. This graph shows the correlation between the average complainlevel (purple) and rainfall (blue) during two months. The rainfall seems to press down the complainlevel. On the other hand a short rain shower, can trigger pollenrelease by […]

dry weather humidity

Humidity and pollenconcentration

Relative humidity (RH) is the ratio of the partial pressure of water vapor to the equilibrium vapor pressure of water at a given temperature. Relative humidity depends on temperature and the pressure of the system of interest. It requires less water vapor to attain high relative humidity at low temperatures; more water vapor is required […]


Pollencounts by hour

This graph shows data of three sample days. Instead of counting all pollen during one day, the pollen were counted every hour. This results often in interesting insights of pollenconcentrations during the day. In this case you can see peaks during morning, afternoon and evening. Mainly based on different weatherconditions.