Dew as an adaptation measure for climate change -

Abstract

Dew is a frequent atmospheric phenomenon in which water droplets naturally condense upon passively cooled surfaces. Pilot studies showed small yet significant yield, particularly in their contribution to the water budget. This interdisciplinary research couples knowledge from hydrology, geostatistics, modeling, and instrumentation to assess the long term potential of dew and its feasibility for crop and reforestation irrigation in the Mediterranean region. An experimental campaign consisting of 6 sites in differing microclimates and elevations across Lebanon revealed dew harvesting is most successful windward at midrange elevation with average nightly yields of 0.13 mm occurring 55percent of nights during the Mediterranean dry season (April-October) and a maximum yield of 0.35 mm. This experimental data was used to validate a dew prediction model which was thereby applied to develop a dew atlas for the entire Mediterranean region as well as evaluate differences in predicted yield due to anticipated climate change impacts. In addition, experimental data was coupled with ET-based modeling to assess its effectiveness to potentially eliminate the need for reforestation and agricultural irrigation from traditional water resources during the dry season.