ABSTRACT

The present study focusses on the estimation of ET using Mapping Evapotranspiration at high Resolution with Internalized Calibration (METRIC) model over the Sal (Shorea robusta Gaertn.f) forest in the subtropical Doon Valley, India for the dry periods of 2016-18. Parameterization of METRIC model was done for surface temperature (T_s), momentum roughness length (z_om), and surface albedo (α) estimations to make it suitable for Forest ET assessment. Results showed good agreement between the daily ET derived from the METRIC model and observed ET by eddy covariance method at Barkot Flux Tower (BFT) site. Results of parameterized METRIC model showed improvement over non-parameterized model with higher coefficient of determination (0.81), Nash Sutcliffe Efficiency (0.71) and lower Root Mean Square Error (0.48 mm). Average ET for the Sal forest ranged from 1.18-4.78 mm/day. Monthly and seasonal ET was derived using cubic spline interpolation-based time integration of reference ET fraction (ET_rF).

摘要

本研究的重点是在2016-18年干旱的印度亚热带Doon谷的Sal（Shorearobasta Gaertn.f）森林上使用高分辨率的蒸散发图和内部校正（METRIC）模型对ET进行估算。对表面温度（T _s），动量粗糙度长度（z _om）进行METRIC模型的参数化）和地表反照率（α）估算值，使其适合进行森林ET评估。结果表明，从METRIC模型获得的每日ET与通过Barkot Flux Tower（BFT）站点的涡度协方差法观察到的ET之间具有良好的一致性。参数化METRIC模型的结果表明，与非参数化模型相比，改进了，具有更高的测定系数（0.81），纳什·苏克利夫效率（0.71）和更低的均方根误差（0.48 mm）。萨尔森林的平均ET范围为1.18-4.78毫米/天。使用基于三次样条插值的参考ET分数（ET _r F）的时间积分得出月和季节ET 。