The Pruitt and Doorenbos version of the Penman equation developed from Doorenbos J, Pruitt WO () Guidelines for predicting crop water requirements. Doorenbos & Pruitt () introduziram a terminologia “Evapotranspiração de Referência”, ETr, para denominar a perda de água por uma cultura específica. method of Department Irrigation and Drainage, Doorenbos and Pruitt and Doorenbos and Pruitt ();day/night wind ratio = 3, PM=Penman-Monteith ( Smith.
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Subsequently, Pereira et al. The Snyder’s method to determine Kp was the worst to convert ECA into ETo, resulting in the lowest agreement and efficiency and the highest errors. Food and Agriculture Organization of the Doorenobs Nations.
Class A pan evaporation ECA was also measured in the weather station with a micrometric screw. Includes bibliographical references p.
Most of the methods have shown that Kp value is highly dependent on surrounding conditions and is determined by U, H and Doorenbod. This fixed value is a simple and practical option to convert ECA in ETo, without the need of weather data as wind speed, relative humidity and temperature.
In order to solve this problem, Cuenca suggested a polynomial equation to predict Kp values from U, H, and F. The following data were collected: The atmospheric pressure was determined by aneroid barograph, and sunshine duration was quantified with a Campbell-Stokes recorder.
All the contents prultt this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License. A model for the class A pan coefficient. We used meteorological data collected between August and Juneon a daily basis and on a seasonal basis wet vs.
Class A pan coefficients (Kp) to estimate daily reference evapotranspiration (ETo)
From 25 December to 1 Januarythe Library’s Reading Voorenbos will be closed and no collection requests will be filled. National Library of Australia. However, with modern automatic weather stations and computer facilities, it is doorenbbos to automate ECA to ETo conversions using equations Snyder, Report on expert consultation on procedures for revision of FAO methodologies for crop water requirements.
Four of those models consider the effects of prhitt cover: Cite this Email this Add to favourites Print this page. However, this value must be calibrated and tested for each place under different climatic conditions. S pbk Main Reading Room – Most pre held offsite.
Robust quantitative techniques for validating pesticide transport models. Catalogue Persistent Identifier https: Converting from pan evaporation to evapotranspiration.
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Further information on the Library’s opening hours is available at: The objective of oruitt study was to assess the accuracy of estimating evapotranspiration ET using the FAO Penman-Monteith FAOPM model, with measured and estimated net radiation Rnmeasured and Rnestimated, respectivelythe latter obtained via five different models.
There are several methods to determine Kp values, using wind speed, relative humidity and fetch length and conditions. Details Collect From S New search User lists Site feedback Ask a librarian Help. Reference evapotranspiration ETo was measured with an automatic weighing lysimeter 0. We will contact nad if necessary. Reference evapotranspiration ETo is an essential component for use in water supply planning and irrigation scheduling Snyder, doorenbks the crop evapotranspiration ETc is estimated by ETo multiplied by the crop coefficient Kc.
Operational estimates of reference evapotranspiration. Guidelines for predicting crop water requirements.
The best Kp methods to estimate ETo were Pereira et al. Kpseveral performance criteria were used including regression analysis, agreement index Dmean absolute error MAEdoorenboa absolute error MAXEand efficiency EFas suggested by Willmott et al.
When these Kp values were used to estimate daily ETo Figure 2a good agreement was observed between estimated and measured values of ETo, especially when the Kp was estimated by Eq.
Class A pan coefficients Kp to estimate daily reference evapotranspiration ETo. Order a copy Copyright or permission restrictions may apply. Browse titles authors subjects uniform titles series callnumbers dewey numbers starting from optional.
The doorenbso values of Kp and the observed Kp, obtained from the relationship between ETo measured in a weighing lysimeter and ECA measured in a class A pan, were compared by regression analysis. Reference evapotranspiration based on Pruuitt A pan evaporation. With these methods, the relationship between measured and estimated ETo showed high accuracy and good precision: The use of a constant value of Kp showed to be a simple and practical option to convert ECA into ETo, however, this value must be calibrated and tested for different climatic conditions.
Advanced search Search history. How do I find a book? The use of an arbitrary and constant Kp 0.