hayfever

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 […]

allergenic

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 […]