pollen

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.

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 […]

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.

Birch
The Birch is not the first trees in the season which flowers, but it has highly allergenic pollen. Although there is a flowering-calendar which indicates the usual period of flowering, you can see in the graph this can vary a lot. In 2017 there was a birchpollen peak (in the Netherlands) at the end of […]