On the Influence of Oceanic Variability on Air-Sea Heat Fluxes and Boundary Layer Recovery in Hurricanes

影响飓风快速增强的控制因素在科学和预报上仍然存在不确定性。在这个奖项中，研究小组将使用观测数据来测试一个新的理论，该理论是关于在飓风生命周期的关键时期，空气和海洋之间的相互作用，导致这些风暴迅速加强。由于准确预测飓风强度变化的重要性，该项目具有直接的社会意义。该项目还将为研究生提供计划、组织和执行实地实验的机会。该奖项旨在表彰对热带气旋（TCs）中与垂直切变和海洋特征相关的耦合海气相互作用的关键热力学过程的研究。主要的概念理论是，在快速增强期间，由于水分不平衡增强和强烈的表面热通量，海洋热含量高和海面冷却最小的地区对tc施加局部浮力强迫。这一过程导致大气边界层等效势温的快速和持续恢复。为了验证这一假设，PI团队将使用在之前的tc期间收集的数据，并在项目期间与NOAA合作参与新的数据收集。具体研究目标为：1)综合现场大气、海洋资料和卫星海温资料，以以往在不同热含量和上层海洋分层上获得的数据为重点，计算选定大西洋盆地飓风期间的海温、水汽不平衡、整体海气热通量和大气边界层等效位温的恢复；2)通过在风暴通过过程中同时部署海洋和大气廓线仪，观察和了解暖洋涡旋区TC强度变化过程中的海气相互作用；3)根据海洋和大气参数，建立一个表征选定tc的海气相互作用和风暴强度时空变化尺度的框架。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。

The controlling factors that impact the rapid intensification of hurricanes remain a scientific and forecasting uncertainty. In this award, the research team will use observational data to test a new theory about the interaction between the air and sea during the key periods in the hurricane life-cycle that lead to rapid strengthening of these storms. The project has direct societal relevance due to the importance of accurate forecasts of hurricane intensity changes. The project will also provide graduate students with the opportunity to plan, organize, and execute a field experiment. This award is for the investigation of key thermodynamics processes of coupled air-sea interaction in tropical cyclones (TCs) relative to vertical shear and oceanic features. The main conceptual theory is that areas with high oceanic heat content and minimal sea surface cooling exert localized buoyancy forcing on TCs during rapid intensification due to enhanced moisture disequilibrium and intense surface heat fluxes. This process leads to a rapid and sustained recovery of the atmospheric boundary layer equivalent potential temperature. To test this hypothesis, the PI team will use data collected during prior TCs and participate in new data collection in collaboration with NOAA during the period of the project. The specific research objectives are to: 1) Synthesize in-situ atmospheric and oceanographic data and satellite SST data, and compute air-sea temperature and moisture disequilibrium, bulk air-sea heat fluxes, and recovery of atmospheric boundary layer equivalent potential temperature during selected Atlantic-basin hurricanes, focusing on previous data acquired over various levels of OHC and upper-ocean stratification; 2) Observe and understand the air-sea interaction during TC intensity change over warm oceanic eddy regimes by simultaneously deploying oceanic and atmospheric profilers during storm passage; and 3) Develop a framework for characterizing the temporal and spatial scales of variability of the air-sea interaction and storm intensity for the selected TCs in terms of oceanic and atmospheric parameters.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.