Estimation of Evapotranspiration using Spatial and Ground Based Observations for Irrigated Areas of Allahabad

Abstract

A comprehensive study to determine the evapotranspiration for irrigated areas of Allahabad, India using Quantum GIS, Grass GIS, Python programming of SEBAL and Cropwat 8 is made for the period of January to May for 4 years (2015-2018). Landsat 8 data, DEM, weather data like rainfall, temperature (min. & max.), relative humidity, solar radiation, wind speed, and observed PET data which are used for the SEBS model. DEM was downloaded from SRTM and Landsat 8 data taken from USGS. The rainfall and temperature data which is collected from department of Forestry and Environment SHUATS Allahabad. The entire study compares ET estimated from SEBS and Penman Monteith single source approach model. SEBS approach for the estimation of ET and the Penman Monteith single source approach method (FAO 56) concludes the average minimum and maximum value of ET is 1.07 to 5.40. and 1.02 to 3.17. The Spatial and ground based observations of the study area during the day concludes the co relation of SEBS ET and Penman Monteith single source approach method (FAO 56) ET have coefficient of determination R2 = 0.845. Technique were developed for the continuing determination of monthly evapotranspiration from the irrigated areas.