[1] The Penman-Monteith equation is often used to estimate transpiration, but an important limitation to this approach, especially for mountainous forested sites, is an accurate estimate of canopy conductance averaged over the area of interest (Gs). We propose a method for estimating watershed-scale transpiration using estimates of Gs derived from measurements of stable isotopes. To estimate Gs...

This study evaluates the performance of four evapotranspiration methods (Priestley-Taylor, Penman-Monteith, Hargreaves and Makkink) of differing complexity in a semiarid environment in north China. The results are compared to observed water vapour fluxes derived from eddy flux measurements. The analysis became necessary after discharge simulations using an automatically calibrated version of th...

This study is an attempt to find best alternative method to estimate reference evapotranspiration (ETo) for the Nagarjuna Sagar Reservoir Project [NSRP], command area located at Andhra Pradesh, India. When input climatic parameters are insufficient to apply standard Food and Agriculture Organization (FAO) of the United Nations Penman–Monteith (P–M) method. To identify the best alternative clima...

Evaporation losses from a watertight 6.34 ha rain forest catchment under wet maritime tropical conditions in the Luquillo Experimental Forest, Puerto Rico, were determined using complementary hydrological and micrometeorological techniques during 1996 and 1997. At 6.6 mm d−1 for 1996 and 6.0 mm d−1 for 1997, the average evapotranspiration (ET ) of the forest is exceptionally high. Rainfall inte...

from the mathematical point of view, the fao penman-monteith equation shows a homographic function related to the wind speed. the homographic function has horizontal and vertical asymptotes. in this issue horizontal asymptote is applicable; because the vertical asymptote occurs for negative values of wind speed but the negative sign indicates the direction of the wind speed and only the absolut...

been reviewed in final form. Permission, as indicated by the signatures and dates given below, is now granted to submit final copies to the College of Graduate Studies for approval. Abstract Changes in streamflow across the western US illustrate a need to better understand how drought indices derived from climate data track streamflow. Three drought metrics, the (SPEI), and Palmer Drought Sever...

Hidrolik tasarım süreci ve tarımsal sulama yönetiminde evapotranspirasyonun tahmini oldukça önemlidir. Bu çalışmada günlük evapotranspirasyon miktarı için ortalama sıcaklık (S), bağıl nem (N), rüzgâr hızı (R), solar radyasyon (SR) parametreleri kullanılmıştır. Penman-Monteith, FAO (Food and Agriculture Organization) tarafından önerilen standart bir metottur. metoda göre yapılmış (ET0), referans...