Investigation of Low Frequency Atmospheric Oscillations Based on Satellite Data

基于卫星数据的低频大气振荡研究

• 批准号: 8722703
• 负责人: John Stanford
• 金额: $ 22.57万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-05-01 至 1991-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8722703&HistoricalAwards=false
• 关键词: Investigation; Low; Frequency; Atmospheric; Oscillations

Low frequency oscillations (LFO) of the atmosphere, a phenomenon with one-to two-month time scales, have captured the interest of researchers worldwide. Much work has been concentrated on the tropics where the effects were initially discovered. This research project will focus on higher latitudes and, in particular, the stratosphere where this group has been the first to study LFO. The research has four components: 1) Global correlation maps similar to those obtained with MSU microwave analyses (90 mb temperatures) will be calculated for infrared SSU data in the middle and upper stratosphere. 2) LFO vertical structure and propagation from the troposphere to the upper stratosphere will be studied with coherencies (in- and out-of phase correlations by wavenumber) using geopotential height fields and SSU data. Lag-correlation Hovmoller studies will be used to investigate wavepacket behavior. Tropics-higher latitude connections will be assessed with correlations between tropical microwave data and higher latitude/altitude geopotential height and SSU fields. 3) LFO energy propagation and effect on the mean flow will be investigated with Eliassen-Palm flux divergence calculations. An E-vector formulation will be used in regions of strong basic flow zonal asymmetry. Comparison will be made with model predictions. 4) Recently reprocessed mesospheric radiance data fields will be used at Oxford University to search for the existence of LFO above the stratopause. This research is important because it seeks relationships between processes in the high atmosphere and climate as manifested near the surface of the earth. Such relationships should enhance our understanding of climate and our ability to predict its variations.

大气低频振荡（LFO）， 在一到两个月的时间尺度上， 全世界研究人员的兴趣。 了大量工作 主要集中在热带地区， 发现了 这个研究项目将集中在高纬度地区 特别是这个群体所在的平流层 第一个研究LFO的人 该研究有四个组成部分： 1)全局相关图类似于 将计算MSU微波分析（90 mb温度） 在平流层中上部的红外SSU数据。 2)低频振荡垂直结构和传播 对流层到平流层上部的研究将与 相干性（波数的同相和异相相关性） 利用重力场和SSU数据。 滞后相关 Hovmoller研究将用于研究波包 行为 热带-高纬度连接将被评估 热带微波数据和更高的 纬度/高度位势高度和SSU场。 3)低频振荡能量的传播和对平均流的影响将 使用Eliassen-Palm通量发散计算进行研究。 在强碱性的区域将使用E-矢量公式 流动纬向不对称 将与模型进行比较 预测。 4)最近重新处理的中间层辐射数据场 将被牛津大学用来寻找 平流层顶上方的低频振荡。 这项研究很重要，因为它寻求关系， 在高层大气和气候过程之间， 在地球表面附近显现出来。 这种关系 应该增强我们对气候的理解， 预测其变化。