Analysis of Coupling between Oceanic Kelvin Waves and Atmospheric Convection, and Its Impacts on Weather over the Tropical Pacific

海洋开尔文波与大气对流耦合及其对热带太平洋天气的影响分析

• 批准号: 0850642
• 负责人: Paul Roundy
• 金额: $ 35.36万
• 依托单位: SUNY at Albany
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-15 至 2013-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0850642&HistoricalAwards=false
• 关键词: Analysis; Coupling; between; Oceanic; Kelvin

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The westerly wind phase of the Madden-Julian Oscillation (MJO) often triggers oceanic Kelvin waves in the equatorial West Pacific Ocean. Occasionally these waves are associated with eastward moving warm sea surface temperature (SST) anomalies. The anomalously warm ocean destabilizes the atmosphere to convectively coupled waves, and the associated enhanced deep convection accelerates westerly winds to the west of the Kelvin wave crests; this, in turn, amplifies the Kelvin waves. This pattern suggests that oceanic Kelvin waves and atmospheric convection are coupled. Preliminary results indicate that this coupling organizes high impact weather events across the tropical Pacific, including westerly wind bursts and tropical cyclones. While such weather events can occur within the MJO prior to the development of oceanic Kelvin waves, the waves influence the further development of weather. Such coupling to the ocean is not included in traditional views of the MJO. In this project the evolutions of atmospheric structures associated with these convectively coupled oceanic waves will be investigated, as well as their associations with high-impact weather.Observations of such coupled events will be analyzed to diagnose the details of their three dimensional spatial structures in the atmosphere and their evolution over time. Particular attention will be paid to the evolution of weather events in the vicinity of the Kelvin waves, in order to determine how these events participate in the coupling process. The approach is to prepare and analyze composites of many events, to analyze individual cases, and to make a census of the population of all events. Results will contribute to a synoptic-dynamic model for the coupled events and their links with the associated weather.This study will enhance our understanding of the interactions of oceanic Kelvin waves with the MJO, some westerly wind bursts, and tropical cyclones. Broader impacts of this project include the potential to predict the development of coupled events along with their associated extreme weather. This work should lead to further analyses of the potential connections between the intraseasonal coupling and the evolution of El Nino. The project will support the work of a beginning investigator and the training of a graduate student.

该奖项是根据2009年的《美国复苏与再投资法》（公法111-5）资助的。马德登 - 朱利安振荡的西风阶段（MJO）经常触发西部太平洋赤道海洋海洋浪潮。有时，这些波浪与向东移动的温暖海面温度（SST）异常有关。异常温暖的海洋破坏了大气使对流耦合的波浪，相关的增强对流会加速西风，沿开尔文波峰的西部。反过来，这放大了开尔文波。这种模式表明海洋开尔文波和大气对流是耦合的。初步结果表明，这种耦合组织了整个热带太平洋的影响很高的天气事件，包括西风爆发和热带气旋。尽管在海洋开尔文波的发展之前，可能发生这种天气事件，但海浪影响了天气的进一步发展。这种与海洋的耦合不包括在MJO的传统观点中。在该项目中，将研究与这些对流耦合海浪相关的大气结构的演变，以及它们与高影响力天气的关联。将分析此类耦合事件的观察，以诊断大气中的三维空间结构的细节，并随着时间的推移而演变。为了确定这些事件如何参与耦合过程，将特别注意在开尔文波附近的天气事件的演变。该方法是准备和分析许多事件的复合材料，分析单个案例并对所有事件的人口进行普查。结果将有助于耦合事件的概要动力模型及其与相关天气的联系。这项研究将增强我们对海洋开尔文波与MJO的相互作用的理解，一些西风风爆发和热带气旋。该项目的更广泛的影响包括预测耦合事件的发展及其相关的极端天气的潜力。这项工作应导致对季节内耦合与El Nino的演变之间的潜在联系进一步分析。该项目将支持初学调查员的工作和研究生的培训。