Evaluation of Pan Coefficient Models and Trend Analysis for a Station in Coastal Andhra Pradesh

Abstract

Irrigation scheduling needs an accurate estimation of crop water requirement and can be done using pan evaporation data which is easily available across the country at various meteorological stations. This study aims to evaluate different K models for a station in coastal Andhra Pradesh, India. A10-year meteorological data from 2006 to 2015 was used for p the study. The results indicated that the Snyder method was able to successfully estimate K and ET accurately on an p 0 annual time scale and during the months of January to September. However, Cuenca and FAO-56 K equation for dry p fetch gave a better result during the months of October to December. The trend detection for the estimates was taken up for the study period. The trend analysis showed that the K estimated by FAO 56 PM showed some declining trend p whereas the K estimated by the other models in the study showed positive trend during the study period for the region.