Dew: The mysterious precipitation
Dew has fascinated Man and been a subject of interest since ancient times. Numerous references to dew can be found in the Bible and classical Greek and Chinese literature. In low rainfall regions, small animals rely on dew water to survive. And in arid regions microorganisms such as cyanobacteria require dew as a moisture source to form biological sand crusts to stabilize mobile dunes. A unique optical instrument was designed to enable remote and non-destructive measurement of surface wetness and leaf water content. A complex meteorological field experiment in the Negev desert, Israel, which also included passive dew collection tests and various soil moisture measurements, showed that daily dew input is around 0.2 L per m2 per night. A model was developed using field meteorological and soil moisture measurements to study dew formation, moisture transport and evaporation from biological sand crusts. We now better understand the factors controlling such processes.
proefschrift: “On dew and micrometeorology in an arid coastal ecosystem“