Reference Crop Evapotranspiration from Temperature
19 Oct 1985-Applied Engineering in Agriculture (American Society of Agricultural and Biological Engineers)-Vol. 1, Iss: 2, pp 96-99
TL;DR: In this paper, an equation is presented that estimates ETo from measured values of daily or mean values of maximum and minimum temperature. But this equation is compared with various other methods for estimating ETo.
Abstract: MEASURED lysimeter evapotranspiration of Alta fescue grass (a cool season grass) is taken as an index of reference crop evapotranspiration (ETo). An equation is presented that estimates ETo from measured values of daily or mean values of maximum and minimum temperature. This equation is compared with various other methods for estimating ETo. The equation was developed using eight years of daily lysimeter data from Davis, California and used to estimate values of ETo for other locations. Comparisons with other methods with measured cool season grass evapotranspiration at Aspendale, Australia; Lompoc, California; and Seabrook, New Jersey; with lysimeter data from Damin, Haiti; and with the modified Penman for various locations in Bangladesh indicated that the method usually does not require local calibration and that the estimated values are probably as reliable and useable as those from the other estimating methods used for comparison. Considering the scarcity of complete and reliable climatic data for estimating crop water requirements in developing countries, this proposed method can do much to improve irrigation planning design and scheduling in the developing countries.
Citations
More filters
TL;DR: A conceptual, continuous time model called SWAT (Soil and Water Assessment Tool) was developed to assist water resource managers in assessing the impact of management on water supplies and nonpoint source pollution in watersheds and large river basins as discussed by the authors.
Abstract: A conceptual, continuous time model called SWAT (Soil and Water Assessment Tool) was developed to assist water resource managers in assessing the impact of management on water supplies and nonpoint source pollution in watersheds and large river basins. The model is currently being utilized in several large area projects by EPA, NOAA, NRCS and others to estimate the off-site impacts of climate and management on water use, nonpoint source loadings, and pesticide contamination. Model development, operation, limitations, and assumptions are discussed and components of the model are described. In Part II, a GIS input/output interface is presented along with model validation on three basins within the Upper Trinity basin in Texas.
6,674 citations
Goddard Institute for Space Studies1, Columbia University2, University of Chicago3, University of East Anglia4, Potsdam Institute for Climate Impact Research5, Karlsruhe Institute of Technology6, University of Florida7, Swiss Federal Institute of Aquatic Science and Technology8, International Institute for Applied Systems Analysis9, Netherlands Environmental Assessment Agency10, University of Natural Resources and Life Sciences, Vienna11
TL;DR: Uncertainties related to the representation of carbon dioxide, nitrogen, and high temperature effects demonstrated here show that further research is urgently needed to better understand effects of climate change on agricultural production and to devise targeted adaptation strategies.
Abstract: Here we present the results from an intercomparison of multiple global gridded crop models (GGCMs) within the framework of the Agricultural Model Intercomparison and Improvement Project and the Inter-Sectoral Impacts Model Intercomparison Project. Results indicate strong negative effects of climate change, especially at higher levels of warming and at low latitudes; models that include explicit nitrogen stress project more severe impacts. Across seven GGCMs, five global climate models, and four representative concentration pathways, model agreement on direction of yield changes is found in many major agricultural regions at both low and high latitudes; however, reducing uncertainty in sign of response in mid-latitude regions remains a challenge. Uncertainties related to the representation of carbon dioxide, nitrogen, and high temperature effects demonstrated here show that further research is urgently needed to better understand effects of climate change on agricultural production and to devise targeted adaptation strategies.
1,704 citations
TL;DR: In this paper, the authors used the SWAT (Soil and Water Assessment Tool) to simulate all related processes affecting water quantity, sediment, and nutrient loads in the Thur River basin, which is a direct tributary to the Rhine.
1,571 citations
Cites methods from "Reference Crop Evapotranspiration f..."
...Potential evapotranspiration can be modelled with the Penman–Monteith (Monteith, 1965), Priestley– Taylor (Priestley and Taylor, 1972), or Hargreaves methods (Hargreaves and Samani, 1985), depending on data availability....
[...]
...(Hargreaves and Samani, 1985), depending on data availability....
[...]
03 Aug 2005
TL;DR: In this article, the Task Committee on Standardization of Reference Evapotranspiration of the Environmental and Water Resources Institute of ASCE has proposed a method for the standardization of reference evapotspiration.
Abstract: Prepared by the Task Committee on Standardization of Reference Evapotranspiration of the Environmental and Water Resources Institute of ASCE.
1,236 citations
TL;DR: In this paper, the authors present a collection of 25 figs from the genus "Figs" and discuss the relationship between the two types of figs: figs and figs.
Abstract: 48 pags., 25 figs. Available online 21 December 2013. The definitive version is available at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1097-0088
1,083 citations