The Quasi-Biennial Oscillation (QBO) and Tropical Deep Convection

准两年期振荡（QBO）和热带深对流

• 批准号: 0836539
• 负责人: Marvin Geller
• 金额: $ 35.14万
• 依托单位: SUNY at Stony Brook
• 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: 2008-12-01 至 2013-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0836539&HistoricalAwards=false
• 关键词: Quasi; Biennial; Oscillation; QBO; Tropical

The extent to which the quasi-biennial oscillation (QBO) of the equatorial stratosphere affects tropical systems has been an open question for some time, but little has been resolved. In recent years, there has been great interest in dynamical interactions between the stratosphere and the troposphere, but little work on how stratospheric changes affect tropical deep convection. Some forecasts of Atlantic hurricane activity have used the QBO as one of the predictors, but the physical connection between the QBO and hurricanes has not been explored. This project is an effort to make systematic advances on these problems.Analyses of observations and modeling will be used to investigate the possible influence of the QBO on tropical deep convection. Previous observational analyses and general circulation studies found significant effects of the QBO on tropical deep convection; this project addresses several weaknesses in these studies. A cloud product that eliminates the ambiguity between deep convection and cirrus clouds in OLR (Outgoing Longwave Radiation) data will be used, and ENSO (El Nino-Southern Oscillation) influences on deep convection will be separated from those of the QBO. Because it is difficult, if not impossible, to address causality through statistical studies, cloud-resolving and single-column modeling will be employed to investigate how the QBO might affect tropical deep convection. Background states for the cloud resolving model will be obtained from high vertical-resolution radiosonde data.Broader impacts of this project include the training of a PhD student in a project that combines multiple research approaches: statistical analysis, cloud-resolving modeling, and general circulation modeling, and using state-of-the-art high-performance computing. This work should shed light on the physical basis for one of the predictors of Atlantic hurricane activity and on the vertical resolution needed in models of the upper troposphere-lower stratosphere region to properly account for upper troposphere-lower stratosphere interactions with deep tropical convection.

赤道平流层准两年振荡（QBO）影响热带系统的程度一直是一个悬而未决的问题，但很少得到解决。近年来，人们对平流层和对流层之间的动力相互作用产生了极大的兴趣，但对平流层变化如何影响热带深对流的研究却很少。一些对大西洋飓风活动的预测使用QBO作为预测因子之一，但QBO和飓风之间的物理联系尚未被探索。本计画将利用观测资料分析与模式模拟来探讨准两年振荡对热带深对流的可能影响。先前的观测分析和大气环流研究发现QBO对热带深对流有显著影响，本项目解决了这些研究中的几个弱点。将使用消除OLR（向外长波辐射）数据中深对流和卷云之间模糊性的云产品，并将ENSO（厄尔尼诺-南方涛动）对深对流的影响与QBO的影响分开。由于通过统计研究很难（如果不是不可能的话）解决因果关系，因此将采用云解析和单列模式来研究QBO如何影响热带深对流。云解析模型的背景状态将从高垂直分辨率无线电探空仪数据中获得。该项目的更广泛影响包括在一个项目中培训一名博士生，该项目结合了多种研究方法：统计分析，云解析建模和大气环流建模，并使用最先进的高性能计算。这项工作将有助于阐明大西洋飓风活动预测因子之一的物理基础，以及对流层上部-平流层下部区域模型所需的垂直分辨率，以适当说明对流层上部-平流层下部与热带深层对流的相互作用。