Higher emissions scenarios lead to more extreme flooding in the United States

Understanding projected changes in flooding across the contiguous United States (CONUS) helps increase our capability to adapt to and mitigate against this hazard. Here, we assess future changes in flooding across CONUS using outputs from 28 global climate models and four scenarios of the Coupled Model Intercomparison Project Phase 6. We find that CONUS is projected to experience an overall increase in flooding, especially under higher emission scenarios; there are subregional differences, with the Southeast (Great Plains of the North and Southwest) showing higher tendency towards increasing (decreasing) flooding due to changes in flood processes at the seasonal scale. Moreover, even though trends may not be detected in the historical period, these projected future trends highlight the current needs for incorporating climate change in the future infrastructure designs and management of the water resources.厘清美国本土（CONUS）范围内洪水的预估变化，有助于提升我们应对并减轻此类灾害的能力。本研究依托28个全球气候模式的输出结果与耦合模式比较计划第六阶段（CMIP6）的4种情景，对美国本土（CONUS）范围内洪水的未来变化展开评估。研究结果显示，美国本土（CONUS）的洪水整体呈加剧趋势，在高排放情景下尤为显著；同时存在子区域差异：东南部、北部大平原及西南部地区，因季节尺度洪水过程的变化，分别呈现出更高的洪水加剧或减缓趋势。此外，尽管在历史时段中尚未能检测到明确的洪水趋势变化，但这些预估的未来趋势凸显了当前亟需将气候变化因素纳入未来基础设施设计与水资源管理工作的必要性。