El Nino-Southern Oscillation (ENSO) Interactions with Tropical Atlantic and Indian Oceans

厄尔尼诺-南方涛动(ENSO)是地球气候的主要年际变化。目前对ENSO与热带大西洋和印度洋相互作用的了解有限。然而，这些相互作用似乎对准确预测ENSO结构和演变及其全球影响至关重要。目前的业务模式很难准确预测ENSO及其与其他大洋流域气候模式的相互作用。通过观测分析和数值模拟任务，该奖项的结果可能揭示这些相互作用背后的关键物理过程，并促进我们目前对ENSO动力学、泛热带气候相互作用和一般大尺度大气-海洋相互作用的了解。这反过来可能提供额外的衡量标准，以评估和改进ENSO及其对天气事件的影响的全球模式表示。第一个推力研究了ENSO引起的热带外强迫和热带强迫对热带北大西洋(TNA)海表面温度异常(SSTA)的相对作用，以及TNA SSTA如何通过诱导的Rossby和Kelvin波响应反馈给ENSO。将进行观测分析和理想化的模型实验。第二个推力考察了大西洋尼诺现象和ENSO之间的相互作用。综合分析将阐明在之前的厄尔尼诺和拉尼娜条件下大西洋尼诺的形成机制。将进行耦合和非耦合模式试验，以研究ENSO如何影响大西洋尼诺，大西洋尼诺如何影响随后的ENSO演变，以及模式偏差对遥远的大西洋强迫有多大影响。第三个重点是研究ENSO如何影响印度洋偶极子(IOD)，以及印度洋盆地变暖在多大程度上有助于厄尔尼诺现象的转变。重点将放在厄尔尼诺现象发展期间对厄尔尼诺现象的赤道对称和反对称环流反应以及对北方冬季IDO降雨型的线性和非线性风反应的影响。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The El Niño-Southern Oscillation (ENSO) is the dominant interannual variability in the Earth’s climate. Current understanding of the interactions between ENSO and tropical Atlantic and Indian Ocean is limited. However, these interactions are seemingly crucial for accurate prediction of ENSO structure and evolution and its global impact. Current operational models have difficulty accurately predicting ENSO and its interactions with climate modes in other ocean basins. Through observational analyses and numerical modeling tasks, results from this award may reveal key physical processes behind these interactions and advance our current knowledge of ENSO dynamics, pan-tropical climate interactions, and general large-scale atmosphere-ocean interactions. This in turn may provide additional metrics to assess and improve global model representations of ENSO and its influence on weather events.The award has three research thrusts. The first thrust investigates the relative roles of ENSO-induced extratropical and tropical forcing of sea surface temperature anomaly (SSTA) in the tropical North Atlantic (TNA) and how the TNA SSTA may feedback to ENSO through induced Rossby and Kelvin wave responses. Observational analyses and idealized model experiments will be performed. The second thrust examines the interaction between Atlantic Niño and ENSO. A composite analysis will be conducted to elucidate the formation mechanisms of Atlantic Niño under preceding El Niño and La Niña conditions. Coupled and uncoupled model experiments will be carried out to investigate how ENSO influences Atlantic Niño and how Atlantic Niño impacts subsequent ENSO evolution and to what extent model bias in sea surface temperature affects the remote Atlantic forcing. The third thrust investigates how ENSO influences the Indian Ocean dipole (IOD) and to what extent Indian Ocean basin warming contributes to El Niño turnabout. Focus will be placed on the effect of equatorially symmetric and antisymmetric circulation responses to El Niño during its developing summer and linear and nonlinear wind responses to the boreal winter IDO rainfall pattern.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.