Application of S-SEBI model for crop evapotranspiration using Landsat-8 data over parts of North India

Abstract

Estimation and monitoring of crop evapotranspiration (ET_c) or consumptive water use over large-area holds the key to irrigation management plans and regional drought preparedness. The objective of this study was to estimate ET_c by applying the simplified-surface energy balance index (S-SEBI) model to Landsat-8 data for the 2014–2015 period in parts of North India. An average ET_c was estimated 2.72 and 2.47 in mm day⁻¹ with 0.22, 0.18 standard deviation and 0.11, 0.07 standard error for Kharif and Rabi crops, respectively. On validation part, a close relationship was observed between S-SEBI derived and scintillometer observed evaporative fraction with 0.85 correlation coefficient and 0.86 agreement index. The statistical analysis also endorses the results accuracy and reliability with 0.026 and 0.602, relative root-mean square errors and model efficiency for wheat crop, respectively. The study showed that normalized difference vegetation index and LST are closely related and serve as a proxy for qualitative representation of ET_c.

Keywords:

• Crop evapotranspiration
• S-SEBI model
• Landsat-8
• evaporative fraction
• scintillometer

Acknowledgements

Authors are grateful to the Director, Indian Institute of Remote Sensing, Indian Space Research Organization, Dehradun and Director, CSSTEAP, Dehradun for facilitating this research. Authors also acknowledge to Director, ICAR- Indian Agricultural Research Institute, New Delhi for providing the LAS data which is a part of a collaborative study between IIRS and ICAR-IARI.