Collaborative Research: Westerly Wind Burst Modulation by the Sea-Surface Temperature (SST): from Understanding to El Nino-Southern Oscillation (ENSO) Prediction

合作研究：海面温度（SST）对西风爆发的调节：从理解到厄尔尼诺-南方涛动（ENSO）预测

• 批准号: 0754341
• 负责人: Benjamin Kirtman
• 金额: $ 22.65万
• 依托单位: University of Miami
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-01 至 2011-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0754341&HistoricalAwards=false
• 关键词: Collaborative; Research; Westerly; Wind; Burst

Westerly wind bursts (WWBs) are associated with the onset of major El Nino events. They occur more frequently and energetically and extend farther eastward prior to and during significant El Nino events than in non-El Nino conditions. While these wind events were initially thought to be completely stochastic, more recent analyses indicate that their occurrence and characteristics are at least partially modulated by the large-scale sea-surface temperature (SST). Model studies show that this modulation affects the characteristics of El Ninos as compared to the case of purely stochastic WWBs.This project is divided into two parts. The first, more applied, component is the implementation of an empirical WWB parameterization into a state-of-the-art El Nino-Southern Oscillation (ENSO) prediction model, in an effort to improve the skill of ENSO prediction and to assess the impact of parameterized WWBs on predictability. A previously developed empirical semi-stochastic observationally-motivated WWB model will be applied in the NCAR CCSM3.0 (National Center for Atmospheric Research Community Climate System Model 3.0) coupled ocean-atmosphere model, and this model will be used as an ENSO prediction model. The mutual effects of the WWB model and the coupled ENSO model on each other will be studied, along with the effects of the WWBs on the ENSO simulation, on the predictability of ENSO, and on the spread of predictions in the model. The second part is an effort to understand the basic mechanisms of WWBs and the dynamics of their dependence on the large-scale SST field. A cloud-resolving atmospheric model capable of producing WWBs will be run in a near-global configuration using the diabatic acceleration and rescaling (DARE) approach. The DARE model will be supplemented with analyses of observed wind and outgoing longwave radiation and with several simple models. It is intended that this strategy will result in an understanding of how the SST controls WWBs and will expose the mechanisms for the initiation and termination of the convective activity that creates WWBs.The broader impacts of this project are in contributing to improved skill in predicting ENSO, with the resulting social and economic benefits. Two graduate students will be trained: one at Harvard and one at Miami.

西风风爆发（WWB）与重大的El Nino事件的发作有关。它们发生在重大的El Nino事件之前和在非EL NINO条件下，更频繁，充满活力，并在较大的El Nino事件发生前向东延伸。尽管最初认为这些风事件是完全随机的，但最新的分析表明，它们的发生和特征至少通过大规模的海面温度（SST）部分调节。模型研究表明，与纯粹随机WWB相比，该调制会影响El Ninos的特征。该项目分为两部分。首先应用的组成部分是将经验WWB参数化实施到最先进的El Nino-Southern振荡（ENSO）预测模型中，以提高ENSO预测的技能并评估参数化WWB对可预测性的影响。先前开发的经验半传播的观察性WWB模型将在NCAR CCSM3.0（国家大气研究社区气候系统模型3.0）中应用于海洋 - 大气模型，并且该模型将用作ENSO预测模型。将研究WWB模型和耦合ENSO模型对彼此的相互影响，以及WWB对ENSO模拟，ENSO的可预测性以及模型中预测的扩散的影响。第二部分是努力了解WWB的基本机制及其对大规模SST领域的依赖的动力学。能够生产WWB的云分辨大气模型将使用糖尿病加速度和重新缩放（DARE）方法以几乎全球的配置运行。 DARE模型将补充观察到的风和外向辐射的分析以及几个简单的模型。目的是，该策略将导致了解SST如何控制WWB，并将揭示产生WWB的对流活动的启动和终止的机制。该项目的更广泛影响有助于改善ENSO的技能，从而获得社会和经济利益。将对两名研究生进行培训：一名在哈佛大学，一名在迈阿密进行培训。