Exploring Estimation of Evaporation in Dry Climates Using a Class ‘A’ Evaporation PanFarai Malvern Simba*, Alois Matorevhu, David Chikodzi and Talent Murwendo
Department of Physics, Geography and Environmental Science, Great Zimbabwe University, Zimbabwe
- *Corresponding Author:
- Farai Malvern Simba
Department of Physics
Geography and Environmental Science
Great Zimbabwe University, Zimbabwe
E-mail: [email protected]
Received August 19, 2013; Accepted September 16, 2013; Published September 27, 2013
Citation: Simba FM, Matorevhu A, Chikodzi D, Murwendo T (2013) Exploring Estimation of Evaporation in Dry Climates Using a Class ‘A’ Evaporation Pan. Irrigat Drainage Sys Eng 2:109. doi:10.4172/2168-9768.1000109
Copyright: © 2013 Simba FM, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
The rate of evaporation in dry climates is a concern and needs to be assessed and quantified for planning in water management activities. The main objective of the study was to investigate evaporation rate of a bare ground in Masvingo district in Zimbabwe using a class ‘A’ evaporation pan. Specific objectives include calibrating the pan using the FAO-Penman Monteith (P-M) method and obtaining typical evaporation rates for the area which could be extended to represent areas of relatively similar climates. To achieve these objectives an evaporation pan was installed on a wooden grid platform near a weather station that recorded wind speed, air temperature, humidity, maximum and minimum temperatures. Considering fetch dimensions the pan results were correlated against P-M method results to give pan calibration coefficient and the slope of the curve gave a Kpan of 0.91 and changes in water depths with respect to pan dimensions gave average evaporation rates of 5.1 mm/day at mean maximum temperature of 24.9°C. The evaporation rates obtained were not sustainable in the long term if water harnessing and conservation strategies are not employed.