水文循环模拟中蒸散发估算方法综述

为选取基于水文循环估算蒸散发方法提供依据, 首先对常用水文模型中蒸散发估算方法进行回顾, 根据其物理机理的强弱性, 将水文模型中蒸散估算方法分为整体折算法和分类汇总法。当前水文模型中整体折算法占较大比重, 它们之间的差异有两点:一是潜在蒸散发估算方法不同;二是土壤干燥度折算函数不同;研究表明:由于水文模型存在不确定性及Penman-Monteith 方法具有较高资料要求, 致使模拟中使用该方法与使用其它简化经验公式相似或更差的水文循环模拟效果。所以对于不同水文模型, 如何选取与之复杂程度相兼容的潜在蒸散发估算方程和土壤干燥度折算函数来降低模型的不确定性需进一步讨论。在此基础上, 预估基于水文循环估算蒸散发方法朝着复杂机理化和简单实用化两个方向发展。

A review of evapotranspiration estimation methods in hydrological Models

Actual evapotranspiration is a key process of hydrological cycle and a sole term that links land surface water balance equation and land surface energy balance equation. Evapotranspiration plays a key role in simulating hydrological effect of climate change, and a review of evapotranspiration estimation methods in hydrological models is of vital importance. This paper firstly summarizes the evapotranspiration estimation methods in hydrological models and then classifies them into integrated discounting methods and classification gathering methods by their mechanism. Integrated discounting methods are usually used in hydrological models and two differences exist among these methods, one is in the potential evaporation estimation methods, and the other difference is the function for defining relationship between potential evaporation and actual evapotranspiration. Due to the higher information requirements of the Penman-Monteith method and the existing uncertainty in those data, simplified empirical methods for calculating potential and actual evapotranspiration are widely used in hydrological models. Different evapotranspiration calculation methods are used in different hydrological models, and importance and difficulty in the selection of most suitable evapotranspiration methods in various hydrological models with different complexity is discussed. Finally, this paper points out the development direction of the evapotranspiration estimating methods in hydrological models.