University of Connecticut, Department of Civil & Environmental Engineering, 261 Glenbrook Rd, Storrs, CT, 06269, USA.
Florida Institute of Technology, Department of Mechanical and Civil Engineering, Melbourne, FL, 32901, USA.
Sci Rep. 2020 Mar 20;10(1):5175. doi: 10.1038/s41598-020-61533-x.
An improved understanding of changes in flood hazard and the underlying driving mechanisms is critical for predicting future changes for better adaptation strategies. While recent increases in flooding across the world have been partly attributed to a range of atmospheric or landscape drivers, one often-forgotten driver of changes in flood properties is the variability of river conveyance capacity. This paper proposes a new framework for connecting flood changes to longitudinal variability in river conveyance, precipitation climatology, flows and sediment connectivity. We present a first step, based on a regional analysis, towards a longer-term research effort that is required to decipher the circular causality between floods and rivers. The results show how this system of interacting units in the atmospheric, hydrologic and geomorphological realm function as a nonlinear filter that fundamentally alters the frequency of flood events. To revise and refine our estimation of future flood risk, this work highlights that multidriver attribution studies are needed, that include boundary conditions such as underlying climate, water and sediment connectivity, and explicit estimations of river conveyance properties.
提高对洪水危险变化及其潜在驱动机制的认识，对于预测未来变化以制定更好的适应策略至关重要。尽管最近世界各地的洪水泛滥部分归因于一系列大气或景观驱动因素，但人们常常忽略了改变洪水特性的一个驱动因素是河道输送能力的可变性。本文提出了一个将洪水变化与河道输送、降水气候、水流和泥沙连通性的纵向变化联系起来的新框架。我们基于区域分析提出了一个初步步骤，旨在开展更长期的研究工作，以破解洪水与河流之间的循环因果关系。结果表明，大气、水文和地貌领域中相互作用的单元系统如何作为一个非线性滤波器，从根本上改变洪水事件的频率。为了修正和完善我们对未来洪水风险的估计，这项工作强调需要进行多驱动因素归因研究，包括潜在气候、水和泥沙连通性等边界条件，以及河道输送特性的明确估算。
