Using lake sediment archives to improve understanding of flood magnitude and frequency: Recent extreme flooding in northwest UK
Using lake sediment archives to improve understanding of flood magnitude and frequency: Recent extreme flooding in northwest UK
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DOI：
10.1002/esp.4650
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发表时间：
2019-06
影响因子：
3.3
通讯作者：
R. Chiverrell;D. Sear;J. Warburton;N. Macdonald;D. Schillereff;J. Dearing;I. Croudace;J. Brown;J. Bradley
中科院分区：
文献类型：
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作者：
R. Chiverrell;D. Sear;J. Warburton;N. Macdonald;D. Schillereff;J. Dearing;I. Croudace;J. Brown;J. Bradley
我们介绍了英国第一次利用湖泊沉积物定量重建古洪水，并表明对于英格兰西北部的一个大流域来说，从1990年到现在的毁灭性洪水集群在这558年的古记录中是前所未有的。我们的方法用连续的湖泊沉积数据增强了传统的洪水震级和频率(FMF)分析，以提供对洪水震级复发概率的更长期的视角。2009年的洪水是558年以来最大的一次，其重现间隔(1：2,200年)大于使用较短历时的单站记录(1：1,700年)进行的常规洪水估计。洪水期与气候指数的相关性是非平稳的，但1990-2018年的集群与北半球变暖和正的大西洋年代际涛动有关。监测记录很少捕捉到最大的洪水，我们的古洪水系列表明，对于这个集水区，这种遗漏破坏了对未来风险的评估。我们的方法提供了一个范例，说明如何从世界各地的湖泊及其集水区很好地获得百年古洪水重建。©2019作者。地球表面过程和地貌由John Wiley&Sons Ltd.出版。
We present the first quantitative reconstruction of palaeofloods using lake sediments for the UK and show that for a large catchment in NW England the cluster of devastating floods from 1990 to present is without precedent in this 558‐year palaeo‐record. Our approach augments conventional flood magnitude and frequency (FMF) analyses with continuous lake sedimentary data to provide a longer‐term perspective on flood magnitude recurrence probabilities. The 2009 flood, the largest in >558 years, had a recurrence interval larger (1:2,200 year) than revealed by conventional flood estimation using shorter duration gauged single station records (1:1,700 year). Flood‐rich periods are non‐stationary in their correlation with climate indices, but the 1990‐2018 cluster is associated with warmer Northern Hemisphere Temperatures and positive Atlantic Multidecadal Oscillation. Monitored records rarely capture the largest floods and our palaeoflood series shows, for this catchment, such omissions undermine evaluations of future risk. Our approach provides an exemplar of how to derive centennial palaeoflood reconstructions from lakes coupled well with their catchments around the world. © 2019 The Authors. Earth Surface Processes and Landforms Published by John Wiley & Sons Ltd.