Temporal investigation of flow variability in Scottish rivers using wavelet analysis
Temporal investigation of flow variability in Scottish rivers using wavelet analysis
复制标题
使用小波分析对苏格兰河流流量变化进行时间研究
DOI：
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发表时间：
2012
期刊：
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通讯作者：
D. Fischbacher‐Smith
中科院分区：
文献类型：
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作者：
F. Villoria;M. Franco‐Villoria;M. Scott;T. Hoey;D. Fischbacher‐Smith
河流流量记录是洪水风险评估的基础。在苏格兰，《洪水风险管理法》（2009年）的目标是通过改进河流流量模型，并考虑到未来潜在的气候变化，改善洪水风险管理。小波分析是一种可能的方法，用于检测和比较趋势，研究空间异质性和非平稳环境时间序列中的显著变化时期。从一组9苏格兰河流的小波分析的结果证实了东部和西部之间的河流流量最大值的差异，已在以前的研究中指出，沿着与季节性模式的变化，可能与外部气候驱动因素，包括北大西洋涛动和大西洋年代际振荡。这种影响（作用于几个时间尺度，主要是一年一次）不是恒定的，在时间上（从1987年起更强）和空间上都有变化，可能存在集水面积效应，突出了在区域一级评估洪水风险的重要性。该研究目前正在扩展到另外26条河流，以更好地了解极端河流流量的空间依赖性，这将有助于改善洪水风险管理。
River flow records form the basis of flood risk estimates. In Scotland, the Flood Risk Management Act (2009) has the objective of improving flood risk management by improved modelling of river flows taking into account potential future climate change. Wavelet analysis is presented here as a possible method for detecting and comparing trends, investigating spatial heterogeneity and periods of significant variability in nonstationary environmental time series. The results from a wavelet analysis of a set of 9 Scottish rivers confirm a difference in river flow maxima between the East and the West that has been pointed out in previous studies, along with changes in the seasonal patterns that may be linked to external climatic drivers, including the North Atlantic Oscillation and the Atlantic Multidecadal Oscillation. Such influences (which act on several time scales, the principal one being annual) are not constant and vary both temporally (being stronger from 1987 onwards) and spatially, with a possible catchment size effect, highlighting the importance of assessing flood risk at a regional level. The study is currently being extended to a further 26 rivers to gain a better understanding of the spatial dependence in extreme river flows, which will contribute to the improvement of flood risk management.