基于GLDAS-Noah模型的闽江流域实际蒸散发评估

以亚热带季风区的典型流域——闽江流域为研究区域，根据Penman-Monteith（P-M）公式和双作物系数法，计算了闽江流域内8个气象观测站点的实际蒸散量，并评估了GLDAS-Noah实际蒸散产品在闽江流域的适用性。在此基础上，基于GLDAS-Noah实际蒸散发数据，解读了2000—2019年闽江流域的实际蒸散量的变化特征。结果表明：① GLDAS-Noah实际蒸散发数据在闽江流域的适用性较好(R²>0.9，NSE>0.8)；② 2000年以来闽江流域的实际蒸散发呈增加趋势（3.86 mm/a，P < 0.01），且存在显著的季节差异，表现为冬季和春季的增加速率要大于夏季和秋季；③ 闽江流域冬季和春季蒸散发增加与气温密切相关，冬季蒸散发与冬季气温呈微弱正相关（ R = 0.27），春季蒸散发的增加与春季升温密切相关（R = 0.79）。

Assessment of Actual Evapotranspiration in the Minjiang River Basin Based on the GLDAS-Noah Model

Evapotranspiration is one of the critical processes in the surface water cycle. Assessment of evapotranspiration and its characterization is essential for understanding the regional water cycle processes. We used the Penman-Monteith (P-M) equation and the two-crop coefficient method to calculate the actual evapotranspiration in the Minjiang River Basin. Meanwhile, used P-M results to evaluate the applicability of the GLDAS-Noah actual evapotranspiration product in the Minjiang River Basin. Then, the GLDAS-Noah actual evapotranspiration product is used to analyze spatial and temporal patterns of actual evapotranspiration in the Minjiang River Basin from 2000 to 2019. The results show that: 1) The GLDAS-Noah actual evapotranspiration product has good applicability (R² > 0.9 and NSE > 0.8) in the Minjiang River Basin; 2) The actual evapotranspiration in the Minjiang River Basin has been increasing since 2000 (3.86 mm/a, P = 0.0086), and there are significant seasonal differences, showing that the increase rate in winter and spring is more significant than that in summer and autumn; 3) The increase in winter and spring evapotranspiration in the Minjiang River Basin was closely related to air temperature. There is a weak positive correlation between winter evapotranspiration and winter air temperature (R = 0.27) and an increase in spring evapotranspiration closely related to spring warming (R = 0.79). The results of the study help to deepen the understanding of the evapotranspiration characteristics of the Minjiang River Basin in the context of global warming and provide an experimental basis for assessing the eco-hydrological processes in the Minjiang River Basin based on the GLDAS-Noah model products.