Estimation of dew resources in Valparaíso, Chile, using available meteorological data and semi analytical modeling

Abstract

In arid regions, dew can provide a potential supplementary water resource, which is relatively meager compared to actual rainfall but with a more regular distribution of events throughout the year, even during periods of drought. Thus, quantifying the dew potential in different locations is of utmost interest. This study aims to quantify the available dew resources in the coastal Valparaíso region, using a semi-analytical model proposed by Beysens in 2016, depending on four meteorological data: air and dew temperatures, wind velocity, and cloud coverage. These data were obtained from the Chilean Meteorological State Service website for the Rodelillo site, which has one value per hour. Three complete years were considered, from 2019 to 2021, showing total amounts of rain precipitation ranging from 110 to 400 mm, with rain mainly concentrated during winter. Dew estimations were found to be quite regular during the year, with an average of 2.2 mm per month, and showing a positive evolution from one year to another, with total amounts respectively equal to 27 mm (2019), 30 mm (2020), and 34 mm (2021). This interesting result indicates that the region of coastal central Chile presents a high potential for dew harvesting and a resource which, contrary to rain, whose amplitude diminishes continuously, is likely to increase.