基于Ameriflux通量观测数据的Hi-GLASS潜热通量产品验证

Validation of Hi-GLASS products for latent heat flux based on Ameriflux observation data

潜热通量产品的验证与分析对于研究气候变化及能量循环具有重要意义。全球陆表高分辨率蒸散产品(high resolution global lAnd surface evapotranspiration product,Hi-GLASS ET)融合了5种传统蒸散算法,能够生产出较高精度的陆表潜热通量产品,但目前没有针对此产品的验证研究。利用Ameriflux通量观测站点的潜热通量观测值与相应的Hi-GLASS陆表潜热通量产品估算值进行对比,获取多组有效验证数据。验证结果显示,所选站点实际观测值与产品估算值的决定系数(R 2)为0.6,均方根误差(RMSE)为34.4 W/m^(2),平均偏差(Bias)为-13.4 W/m^(2),克林-古普塔效率(Kling-Gupta efficiency,KGE)为0.49,Hi-GLASS潜热通量产品具有较高的精度,算法的拟合结果较好;此外,空间分布也表明Hi-GLASS陆表潜热通量产品符合正常的自然规律。由于数据获取的局限性,仅采用了美国地区18个站点数据对产品进行验证,在其他地区仍需进一步验证。

The validation and analysis of latent heat flux products are critical for research on climate change and energy circulation.High-resolution global land surface satellite evapotranspiration(Hi-GLASS ET)products,which integrate five traditional evapotranspiration algorithms,can produce high-precision products for land surface latent heat flux.However,these products are yet to be validated.This study obtained multiple sets of valid validation data by comparing the latent heat flux observed values from Ameriflux flux observation sites with the corresponding estimated values of Hi-GLASS land surface latent heat flux products.The validation results yielded a squared correlation coefficient(R 2)of 0.6,a root mean square error(RMSE)of 34.4 W/m^(2),an average bias of-13.4 W/m^(2),and Kling-Gupta efficiency(KGE)of 0.49.These suggest that Hi-GLASS latent heat flux products boast high precision and that their algorithms enjoy satisfactory fitting results.In addition,spatial distributions imply that Hi-GLASS latent heat flux products conform to normal natural laws.Due to data acquisition limitations,the validation of this study was conducted based on data from only 18 sites in the U.S.,and further validation using data from other areas is required.