Satellite-derived evapotranspiration across southern Africa

Programming code for: Evaluating the performance of satellite-derived evapotranspiration products across varying bioclimates in South Africa This repository hosts the code for the processing of acquired evapotranspiration time series datasets. Summary In this study we aim to evaluate the performance of freely available satellite-derived evapotranspiration products across varying bioclimates in South Africa. Satellite-derived evapotranspiration products were evaluated against in situ observations at a monthly time-step. Evapotranspiration time series datasets from flux towers across South Africa as well as from satellite-derived evapotranspiration products were collated and processed. Metrics used for the evaluation included correlation (Spearman Correlation Coefficient), Percent Bias and Kling-Gupta Efficiency for different temporal levels including overall, log transformed data, interannual and seasonal. The best performing satellite-derived evapotranspiration products were identified and integrated into a mean ensemble model for South Africa, which was then also evaluated. Note: Evapotranspiration refers to the combination of the evaporation of water from the Earths surface and transpiration from vegetation. Repository Components The components of this repository include two primary steps each including a set of method workflow notes and code scripts The two steps include the following: A) Evaluate satellite-derived evapotranspiration products performance Collate and process field-measured and satellite-derived evapotranspiration time series datasets Evaluate the performance of satellite-derived evapotranspiration products B) Select products for an ensemble and evaluate its performance Collate evapotranspiration time series using ensemble Evaluate the ensembles performance用于评估南非不同生物气候区卫星反演蒸散发产品（satellite-derived evapotranspiration products）性能的编程代码 本代码仓库包含已获取的蒸散发时间序列数据集的处理代码。 ## 研究概述 本研究旨在评估南非不同生物气候区各类免费公开的卫星反演蒸散发产品的性能。 研究以月时间步长的原位观测数据为参照，对卫星反演蒸散发产品开展性能评估。研究人员整理并处理了来自南非全境通量塔的蒸散发时间序列数据集，以及卫星反演蒸散发产品数据集。本次评估采用的指标包括相关系数（斯皮尔曼相关系数，Spearman Correlation Coefficient）、相对偏差（Percent Bias）以及克林-古普塔效率（Kling-Gupta Efficiency），评估覆盖多时间尺度维度：整体数据集、对数变换后的数据、年际尺度以及季节尺度。研究筛选出性能最优的卫星反演蒸散发产品，构建南非区域的平均集合模型，并对该集合模型的性能进行了评估。 ## 备注 蒸散发（evapotranspiration）指地球表面水体蒸发与植被蒸腾的综合过程。 ## 仓库组成 本代码仓库包含两大核心步骤，每个步骤均配有配套的方法流程说明文档与代码脚本，具体如下： A) 卫星反演蒸散发产品性能评估 整理并处理野外实测与卫星反演的蒸散发时间序列数据集 评估卫星反演蒸散发产品的性能 B) 筛选集合模型所需产品并评估其性能 基于集合模型整合蒸散发时间序列数据 评估集合模型的性能