Quality analysis of SRTM and HYDRO1K: a case study of flood inundation in Mozambique
Quality analysis of SRTM and HYDRO1K: a case study of flood inundation in Mozambique
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SRTM 和 HYDRO1K 的质量分析：莫桑比克洪水淹没案例研究
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
W. Arnberg
中科院分区：
文献类型：
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作者：
J. Karlsson;W. Arnberg
许多国家仍然缺乏国家数字高程模型（DEM），不得不依赖全球数据集，这可能会对洪水模型结果的可靠性产生负面影响。莫桑比克被认为是南部非洲最容易发生洪水的国家。在这项研究中，两个全球DEM（航天飞机雷达地形使命（SRTM）和HYDRO1K）的质量和精度评估提出了一个简单的静态洪水淹没模型下林波波河流域。这是完成与当地的适合和垂直精度评估的全球数据集在当地的规模，以及洪水范围的模拟在洪泛区进行的水填充DEM根据2000年的洪水事件。垂直精度评估的结果表明，全球DEM可用于局部尺度。然而，在原始DEM上进行的洪水模拟存在不足之处，并且由于对洪水区域的低估和高估而具有误导性，而在本地拟合的DEM上进行的模拟显示出与实际事件更好的一致性。这项研究清楚地表明，在洪水淹没建模中应非常谨慎地使用精度和分辨率有问题的DEM，因为它们可能导致欺骗性的模型预测，并在风险易发地区导致毁灭性的后果。
Many countries still lack national digital elevation models (DEMs) and have to rely on global datasets, which can negatively influence the reliability of flood model results. Mozambique is considered the most risk prone country for floods in Southern Africa. In this study a quality and accuracy assessment of two global DEMs (Shuttle Radar Topography Mission (SRTM) and HYDRO1K) is presented for a simple static flood inundation model of lower Limpopo Basin. This is accomplished with a local fit and vertical accuracy assessment of global datasets on a local scale as well as simulations of flood extent in the floodplain carried out by filling the DEMs with water according to the 2000 flood event. The results from the vertical accuracy assessment show that global DEMs can be used on a local scale. However, flood simulations performed on original DEMs contain inadequacies and are misleading with both under- and overestimation of the flooded area, while simulation performed on locally fitted DEMs shows a better agreement with the actual event. This study clearly shows that DEMs with questionable accuracy and resolution should be used with great caution in flood inundation modelling because they could result in deceptive model predictions, and lead to devastating after-effects in risk prone areas.