Effects of Spatial Resolution in Urban Hydrologic Simulations
Effects of Spatial Resolution in Urban Hydrologic Simulations
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DOI：
10.1061/(asce)he.1943-5584.0000405
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发表时间：
2012-01-01
影响因子：
2.4
通讯作者：
Hellweger, Ferdi L.
中科院分区：
文献类型：
--
作者：
Ghosh, Indrani;Hellweger, Ferdi L.
模型细分用于捕获输入参数的空间异质性，并且众所周知，空间分辨率（即，聚合度）影响模型输出。然而，关于这种影响的普遍共识并不存在。本研究的目的是探讨空间分辨率对城市集水区模式预测的影响，并了解尺度效应的机制。一般方法是开发各种空间分辨率的模型，进行模拟，并比较总流出量和峰值流量的预测。模型的基础上开发的实际排水网络，和人工的基础上产生的分形算法，通过使用人工网络发生器（ANGel）。使用美国环保署的暴雨水管理模型（SWMM）进行模拟，并对50场暴雨的模型输出进行了比较。不同决议预测的年流出总量差别很小。然而，峰值流量表现出双重尺度效应。对于较大的风暴，模型聚合减少了峰值流量，这可以解释为渗透的差异。这种影响主要归因于土壤饱和导水率和坡面流长度的空间分布。对于较小的风暴，聚合增加了峰值流量，这可以解释为地表径流和管道路由的综合影响。使用实际和人工网络的结果是一致的。这项研究表明，不同的过程可以引入尺度效应，这些过程可以在不同的方向上进行（即增加或减少峰值流量），并取决于风暴的特征。DOI：10.1061/（ASCE）HE.1943-5584.0000405。(C)2012年美国土木工程师学会。
Model subdivision is used to capture spatial heterogeneity in input parameters and it is well-established that spatial resolution (i.e., degree of aggregation) affects model output. However, a general consensus about the effect does not exist. The objective of this study was to investigate the effects of spatial resolution on model predictions in an urban catchment, and to understand the mechanism(s) responsible for the scale effect. The general approach is to develop models at various spatial resolutions, perform simulations, and compare the predictions of total outflow volume and peak flow. Models were developed on the basis of actual drainage networks, and artificial ones generated on the basis of a fractal algorithm by using the Artificial Network Generator (ANGel). Simulations were performed by using the EPA Storm Water Management Model (SWMM), and model output was compared for 50 storms. There was very little difference in the total annual outflow volumes predicted by the different resolutions. However, peak flows showed a dual scale effect. For the larger storms, model aggregation reduced peak flows, which can be explained by differences in infiltration. This effect was attributed primarily to the spatial distribution of the soil-saturated hydraulic conductivity and the length of overland flow. For the smaller storms, aggregation increased peak flows, which can be explained by the combined effects of overland flow and conduit routing. The results were consistent using actual and artificial networks. This study illustrates that a scale effect can be introduced by different processes, which can go in different directions (i.e. increase or decrease peak flows) and depend on the storm characteristics. DOI: 10.1061/(ASCE)HE.1943-5584.0000405. (C) 2012 American Society of Civil Engineers.