Department of Civil Engineering, Shibaura Institute of Technology, 3-7-5 Toyosu, Koto-ku, Tokyo, 135-8548, Japan.
Center for Global Environmental Research, National Institute for Environmental Studies, 16-2, Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
Sci Rep. 2021 Feb 12;11(1):3740. doi: 10.1038/s41598-021-83279-w.
Estimates of future flood risk rely on projections from climate models. The relatively few climate models used to analyze future flood risk cannot easily quantify of their associated uncertainties. In this study, we demonstrated that the projected fluvial flood changes estimated by a new generation of climate models, the collectively known as Coupled Model Intercomparison Project Phase 6 (CMIP6), are similar to those estimated by CMIP5. The spatial patterns of the multi-model median signs of change (+ or -) were also very consistent, implying greater confidence in the projections. The model spread changed little over the course of model development, suggesting irreducibility of the model spread due to internal climate variability, and the consistent projections of models from the same institute suggest the potential to reduce uncertainties caused by model differences. Potential global exposure to flooding is projected to be proportional to the degree of warming, and a greater threat is anticipated as populations increase, demonstrating the need for immediate decisions.
未来洪水风险的估计依赖于气候模型的预测。用于分析未来洪水风险的相对较少的气候模型很难量化其相关不确定性。在这项研究中，我们表明，新一代气候模型（统称为耦合模式比较计划第 6 阶段（CMIP6））估计的河流洪水变化预测与 CMIP5 估计的相似。多模式中位数变化（+ 或 -）的空间模式也非常一致，这意味着对预测的信心更大。在模型开发过程中，模型差异变化很小，这表明由于内部气候变率导致模型差异不可减少，并且来自同一研究所的模型的一致预测表明有可能减少由模型差异引起的不确定性。预计全球面临洪水的风险与变暖程度成正比，随着人口增加，预计威胁会更大，这表明需要立即做出决策。
