ABSTRACT
Direct measurements of dew yield have been made using so-called drosometers and involve the initial process of dew condensation and the further process of drop collection. As both processes are of importance in dew water collectors, dew measurements and dew collection even though dew collectors are not specifically designed for measurements. Optical observations of dew can lead, under some assumptions and/or calibration, to the determination of dew volume. By using the spectral reflectance signature of a surface, one can obtain an estimation of soil-surface moisture content. The process of weighing a substrate on which dew forms is the oldest technique to quantitatively evaluate dew yield. A comparison of dew yield using the same condensing materials and thermal isolation beneath is, however, hampered by boundary effects, which depend mainly on the size of the materials and the orientation of the substrate with respect to the air-flow direction.
