The effect on river discharge estimation by considering an interaction between land surface process and river routing process
The effect on river discharge estimation by considering an interaction between land surface process and river routing process
复制标题
考虑地表过程与河流演进过程相互作用对河流流量估算的影响
DOI：
10.5194/piahs-369-81-2015
复制
发表时间：
2015
期刊：
影响因子：
2.6
通讯作者：
Y. Tachikawa
中科院分区：
文献类型：
--
作者：
K. Yorozu;Y. Tachikawa
摘要。有很多研究评估了气候变化对水文循环的影响。然而，它往往侧重于特定的水文过程，而没有考虑水文过程之间的相互作用。在此基础上，建立了考虑水流路径与地表过程相互作用的分布式水文模型，并研究了该模型对河流流量估算的影响。该模型可以考虑水流路线、水田河流的灌溉回水量、作物生长依赖于水和能量状况，以及基于气象、土壤水分和植被状况的蒸散发。为了研究水文过程相互作用对河流流量估算的影响，利用日本气象研究所大气环流模式（MRI-AGCM3.2S）以TL959空间分辨率为强迫数据，建立了湄南河流域近地表气象数据模型。此外，作为已开发模型的一部分，一个流动路径模型被独立应用，使用来自同一GCM的地表和地下径流数据。结果表明，由于灌溉效应的影响，所建立的模型所估计的河流流量比河道路径模型所估计的要小。相比之下，该模型计算的年最大日流量比水流路径模型计算的年最大日流量大24%。假设所建模型中的地表径流量大于水流路径模型中的地表径流量，因为通过灌溉回灌使土壤含水量保持在较高水平。对于日流量第355大的干旱流量，该模型给出的流量是流量路径模型的2.7倍。开发模型的地下径流量似乎大于水流路径模型的地下径流量。本研究的结果表明，在数值模型中考虑水文相互作用可以影响洪水和干旱的估计。
Abstract. There is much research assessing the impact of climate change on the hydrologic cycle. However, it has often focused on a specific hydrologic process, without considering the interaction among hydrologic processes. In this study, a distributed hydrologic model considering the interaction between flow routing and land surface processes was developed, and its effect on river discharge estimation was investigated. The model enables consideration of flow routing, irrigation withdrawal from rivers at paddy fields, crop growth depending on water and energy status, and evapotranspiration based on meteorological, soil water and vegetation status. To examine the effects of hydrologic process interaction on river discharge estimation, a developed model was applied to the Chao Phraya river basin using near surface meteorological data collected by the Japanese Meteorological Research Institute's Atmospheric General Circulation Model (MRI-AGCM3.2S) with TL959 spatial resolution as forcing data. Also, a flow routing model, which was part of the developed model, was applied independently, using surface and subsurface runoff data from the same GCM. In the results, the developed model tended to estimate a smaller river discharge than was estimated by the river routing model, because of the irrigation effect. In contrast, the annual maximum daily discharge calculated by the developed model was 24% greater than that by the flow routing model. It is assumed that surface runoff in the developed model was greater than that in the flow routing model because the soil water content was maintained at a high level through irrigation withdrawal. As for drought discharge, which is defined as the 355th largest daily discharge, the developed model gave a discharge 2.7-fold greater than the flow routing model. It seems that subsurface runoff in the developed model was greater than that in the flow routing model. The results of this study suggest that considering hydrologic interaction in a numerical model could affect both flood and drought estimation.