Class A pan evaporation rates in millimetres. In Angola: from Marques, R. 1998. Climate, hydrology and water resources: Angolan sector. Report for OKACOM Diagnostic Assessment. GEF Project Brief. For Maun from HOORC and Botswana Met Services. However, these data are incorrect underestimates and better information is available in Dincer, T. 1976. An introduction to the hydrology and hydrography of the Okavango Delta. In: Proceedings of the symposium on the Okavango Delta and its future utilization. Botswana Society, Gaborone. Namibian data from Namibia Met. Services. The Angolan data includes some Thornthwaite and Penman estimates of potential evapo-transpiration. Origin: Various.