Browsing by Author "Gupta, Vikash"
Now showing 1 - 1 of 1
Results Per Page
Sort Options
ThesisItem Open Access Evaluation of FAO56-pm Et0 model under meteorological data limiting scenarios at semi-arid Hissar district of Haryana(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-08) Gupta, Vikash; Tomar, Arvind SinghThis study was carried out with objectives, (i) to compare performance of FAO56-PM model with derived individual meteorological parameters and their different combinations with full meteorological dataset FAO56-PM estimates, and (ii) to decide minimum meteorological parameters required for acceptable accuracy of obtained ET0 values in comparison to standard FAO56-PM ET0 estimates. The study was carried out in semi-arid climate condition of Hissar district of Haryana using daily meteorological dataset collected for a period of 25 years (1992-2016) from IMD, Pune. Due to severe data gaps, five year (1997, 1999-2002) meteorological data was not considered. The daily meteorological dataset was classified into 52 SMWs and 12 months in tune with CWS-1 format recommended by IMD, Pune for obtaining results on weekly and monthly basis. The performance evaluation of 55 cases of derived individual meteorological parameters and their combinations in comparison to FAO56-PM estimates using full weather dataset was done on the basis of statistical indices namely, agreement index, coefficient of determination, standard error of estimates, weighted root mean square difference. The ranking of these 55 cases was decided on the basis of Global Performance Indicator (GPI) values. MicrosoftTM Excel software was used as computing tool to draw fruitful inferences. The obtained results revealed that (i) saturation vapour pressure estimated using mean air temperature has least influence on FAO56-PM model and can be successfully used if only mean air temperature data is available, (ii) among different combinations of two, three and four derived individual meteorological parameters, combinations esB-Rs, esB-Rs-Ul and ea(k3)-esB-Rs-Ul showed best performance at all timescales, (iii) to get ET0 values at par with standard FAO56-PM model, relative humidity is most important meteorological parameter followed by wind speed and solar radiation, (iv) when reliable data of relative humidity is not available, it will be appropriate to use ea(k3) for estimating actual vapour pressure instead of minimum air temperature, (v) the effect of unavailability of solar radiation data was least on performance of standard FAO56-PM model and it could be accurately estimated by using maximum and minimum air temperature, (vi) in absence of wind speed data, long-term average wind speed of study area must be used, (vii) air temperature (minimum and maximum and/or mean) and long-term average wind speed data are minimum meteorological data required for estimating accurate ET0 values with FAO56-PM model at a place.