Evapotranspiration in high alpine catchments – an important part of the water balance!

• DOI: 10.2166/nh.2012.132
• Publication Date: 2012-04-30T09:54:41Z
• Authors: Mathew Herrnegger; Hans-Peter Nachtn...; Thomas Haiden
• Keywords: Water balance; Water cycle; Elevation (ballistics)

In this paper the third water balance component, actual evapotranspiration (ETA), is analysed. Although rates decrease with increasing altitude, it can be concluded that substantial quantitative differences are found among temperature and energy balance-based techniques for estimating ETA. The objective of study to apply a distributed continuous hydrological model utilise standard meteorological datasets high spatio-temporal resolution (1 km2 60 min) estimate in Alpine Austrian catchments. Compared Hargreaves Thornthwaite methods ASCE-Penman-Monteith approach yields substantially higher potential (ETP) rates, basin-values up 24% compared temperature-based methods. ETP elevation ranges from 6 26 mm per 100 m. ETA differ 15%, 18–28 About 30% annual precipitation evaporated implies even larger correction factors required satisfy runoff. method demonstrated basins north central Alps.