Publications

Shekar, NCS; Hemalatha, HN (2021). Performance Comparison of Penman-Monteith and Priestley-Taylor Models Using MOD16A2 Remote Sensing Product. PURE AND APPLIED GEOPHYSICS, 178(8), 3153-3167.

Abstract
The aim of this work is to develop and evaluate a performance comparison for estimating satellite-based actual evapotranspiration (AET) using the Penman-Monteith (PM) and Priestley-Taylor (PT) approaches and to create a spatial AET map in an ungauged sub-humid tropical river basin. A few studies have compared the PM and PT model performance with a MODIS evapotranspiration data product (MOD16A2). Estimated AET values by the PT approach (AET(PT)), PM model with aerodynamic conductance (Ga) computed using the Leuning equation (AET(PM)), and Ga computed using the Choudhury equation (AET(PMCH)) were extracted for each of the 304 pixels for each day, and pixelwise comparisons were made with the corresponding MOD16A2 AET estimates for validation. As shown by the low RMSE values (0.19-0.23 mm/day), the PM model suggested in this analysis with Ga computed using the (AET(PMCH)) equation turned out to be the better model. Also, using the (AET(PMCH)) equation significantly reduced PBIAS values for all days examined. Topography, land use and land cover (LU/LC), temperature, and moisture availability conditions appear to influence AET variations across the basin. For the eight total Julian days in summer and winter for selected wet (2007) and dry (2012) years the for period 2006-2017, pixelwise maps depicting spatial variability were developed using MATLAB for the AET(PMCH) approach for selected available cloud-free MODIS image data.

DOI:
10.1007/s00024-021-02780-5

ISSN:
0033-4553