PREEVENTS Track 2: Collaborative Research: Predicting Hurricane Risk along the United States East Coast in a Changing Climate

下个世纪飓风活动的变化有可能对美国沿海地区的整个经济格局造成灾难性的影响。不幸的是，对未来飓风风险的预测存在很大的不确定性，因为人们对飓风活动变化的气候驱动因素知之甚少。西大西洋飓风发生的仪器记录非常短，这使得诊断飓风活动的气候控制变得困难，这加剧了这种情况。该项目利用北大西洋西部飓风活动的历史和长期地质重建，将我们对飓风发生的认识扩展到几个世纪甚至几千年前。这种方法可以评估美国东海岸飓风带来的风险是如何变化的。此外，研究人员将使用最先进的数值模型来诊断导致飓风活动变化的关键气候条件，并提供对未来飓风风险的改进预测。从这项工作中吸取的许多经验教训将被更广泛的科学界、规划人员和决策者利用，以提高我们对未来飓风风险可能变化的准备和恢复能力。研究结果将为风险建模提供信息，进而为保险和再保险行业提供信息，以及在城市、州和联邦各级减轻热带气旋危害的努力提供信息。最后，该项目将为研究生、本科生和高中生提供培训和教育下一代科学家的机会。本研究采用综合研究方法来解决两个广泛的问题：1)由于(a)风暴潮和(b)降雨，洪水的风险是如何变化的？2)海洋环流的变化（如大西洋经向翻转环流）和低纬度火山爆发的响应等过程如何调节飓风活动，无论是一般的还是特别针对美国登陆风暴的？重建美国东北部、佛罗里达东海岸和墨西哥湾西北部飓风登陆的过去变化，将结合与热带气旋有关的风暴潮和波浪的流体动力学模拟，以及与tc有关的降雨量的缩小估计。这种方法可以确定在过去一千年中由tc引起的洪水风险的变化。这将构成审查未来风险和审查可能显著改变未来区域登陆概率的关键强迫机制的基线。缩小最新的（CMIP6）全球模型输出，加上浪涌和波浪的水动力学建模，将用于评估当前和未来由tc引起的洪水风险。此外，我们将探讨穿透平流层的火山气溶胶对TC活动的潜在影响。此外，本研究计划检验海洋环流变化对热带气旋的影响，它通过改变热带气旋在接近登陆时可利用的海洋热含量来影响强飓风登陆的概率。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Changes to hurricane activity in the coming century has the potential to catastrophically impact the entire economic landscape of American coastal region. Unfortunately, significant uncertainty in projections of future hurricane risk exist because the climatic drivers of changes in hurricane activity is poorly known. This is exacerbated by the exceedingly short instrumental record of hurricane occurrence in the western Atlantic, which makes diagnosing the climatic controls on hurricane activity difficult. This project utilizes historical and long-term geological reconstructions of hurricane activity in the western North Atlantic, which extends our knowledge of hurricane occurrence back centuries and even millennia. This approach allows assessment of how the risk posed by hurricanes along the east coast of the United States has changed. Further, the researchers will use state of the art numerical models to both diagnose the key climatic conditions that contribute to changes in hurricane activity and to provide improved projections of future hurricane risk. Many of the lessons learned from this work will be used by the broader scientific community and planners and decision-makers to improve our preparedness and resilience to possible future changes in hurricane risk. The results will inform risk modeling, which in turn informs the insurance and re-insurance industries, as well as efforts to mitigate tropical cyclone hazards at the city, state and federal levels. Finally, the project will provide the opportunity to train and educate the next generation of scientists with the engagement of graduate, undergraduate and high school students.This study takes an integrated research approach that addresses two broad questions: 1) How is the risk of floods changing due to (a) storm surge and (b) rainfall? 2) How do processes like changes in ocean circulations (e.g., Atlantic Meridional Overturning Circulation) and the response to low latitude volcanic eruptions modulate hurricane activity, both generally and specifically for US landfalling storms? Reconstruction of past changes in hurricane landfalls along the Northeast US, Florida east coast, and northwestern Gulf of Mexico will be coupled with hydrodynamic modeling of tropical cyclone related storm surges and waves and downscaled estimates of TC-related rainfall. This approach will allow determination of changes in risk of TC-induced flooding over the last millennium. This will form the baseline for examining future risk and for examining critical forcing mechanisms that may significantly alter future regional landfall probabilities. Downscaling the latest (CMIP6) global model output coupled with hydrodynamic modeling of surge and waves will be used to assess current and future risk of TC-induced flooding. In addition, we will explore the potential influence of volcanic aerosols that penetrate the stratosphere on TC activity. Further, this study plans to examine the influence of changes in ocean circulation on TCs, which affects the probability of intense hurricane landfalls by altering the amount of ocean heat content available to TCs close to landfall.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.