Rateb Ashraf, Save Himanshu, Sun Alexander Y, Scanlon Bridget R
Bureau of Economic Geology, Jackson School of Geosciences, The University of Texas at Austin, Austin, TX, 78758, USA.
Center for Space Research, University of Texas at Austin, Austin, TX, 78759, USA.
Sci Rep. 2024 Jun 15;14(1):13841. doi: 10.1038/s41598-024-64491-w.
Floods affect communities and ecosystems worldwide, emphasizing the importance of identifying their precursors and enhancing resilience to these events. Here, we calculated Antecedent Total Water Storage (ATWS) anomalies from the new 5-day (5D) Gravity Recovery and Climate Experiment (GRACE) and its Follow-On (GRACE-FO) satellite solutions to enhance the detection of pre-flood and active flood conditions and to map post-flood storage anomalies. The GRACE data were compared with ~ 3300 flood events reported by the Dartmouth Flood Observatory (2002-2021), revealing distinct ATWS precursor signals in 5D solutions, in contrast to the monthly solutions. Specifically, floods caused by saturation-excess runoff-triggered by persistent rainfall, monsoonal patterns, snowmelt, or rain-on-snow events-show detectable ATWS increases 15 to 50 days before and during floods, providing a valuable opportunity to improve flood monitoring. These 5D solutions also facilitate a more rapid mapping of post-flood storage changes to assess flood recovery from tropical cyclones and sub-monthly weather extremes. Our findings show the promising potential of 5D GRACE solutions, which are still in the development phase, for future integration into operational frameworks to enhance flood detection and recovery, facilitating the rapid analysis of storage changes relative to monthly solutions.
洪水影响着全球的社区和生态系统，凸显了识别洪水前兆以及增强对这些事件恢复力的重要性。在此，我们根据新的5天重力恢复与气候实验（GRACE）及其后续任务（GRACE-FO）卫星数据计算了前期总蓄水量（ATWS）异常，以加强对洪水前和洪水期的探测，并绘制洪水后的蓄水量异常图。将GRACE数据与达特茅斯洪水天文台报告的约3300次洪水事件（2002年至2021年）进行比较，结果显示5天数据解中存在明显的ATWS前兆信号，这与月度数据解形成对比。具体而言，由持续降雨、季风模式、融雪或雨夹雪事件引发的超饱和径流导致的洪水，在洪水前15至50天及洪水期间，ATWS会出现可检测到的增加，这为改进洪水监测提供了宝贵契机。这些5天数据解还便于更快速地绘制洪水后的蓄水量变化图，以评估热带气旋和次月度极端天气后的洪水恢复情况。我们的研究结果表明，仍处于发展阶段的5天GRACE数据解在未来融入业务框架以加强洪水探测和恢复方面具有广阔潜力，相较于月度数据解，它有助于快速分析蓄水量变化。
