High Latitude Mesospheric Dynamic and Chemistry Studies

高纬度中层动力学和化学研究

• 批准号: 9908598
• 负责人: Gary Swenson
• 金额: $ 26.66万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-15 至 2002-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9908598&HistoricalAwards=false
• 关键词: Latitude; Mesospheric; Dynamic; Chemistry; Studies

This study has two objectives:1) a primary objective, to measure and study the Acoustic Gravity Wave (AGW) structure and flux into the mesosphere at Sonderstrom, Greenland, a high latitude station. The studies of structure in airglow imagery can now be used to calculate the vertical flux of horizontal momentum carried by the AGWs with large vertical wavelengths. Airglow imagers are uniquely capable of measuring the AGWs with large phase speeds (short periods) that carry the major portion of the wave momentum flux in the mesosphere. Specifically, comparisons will be made to similar measurements being made at Albuquerque, N.M., a low-mid latitude station, and South Pole station.2) A secondary objective, to make measurements of, and study, mesospheric emissions related to sporadic metal layers in the mesosphere. Recent studies suggest these may involve high latitude layers and, there may be chemical heating associated with some releases.For extracting intrinsic wave measurements, it is important to make Doppler corrections for winds. A meteor radar is now active at Sonderstrom which is able to make this measurement. Rayleigh lidar routinely make scattering measurements of structure in the stratosphere and lower mesosphere and Na lidar in the upper mesosphere. The lidars observe slower speed AGWs that complement the spectrum observed by the airglow. This data will be assimilated and used to 1) quantify the vertical flux of horizontal momentum and energy carried by the waves at Sondrestrom, and 2) compared with data being gathered at a low latitude site, Albuquerque.Atmospheric dynamic and chemical processes at high latitude are unique, especially the thin and sporadic layer phenomena. It is important to resolve the chemical processes during these events through the measurements of airglow chemiluminescent emissions. Routine measurements of airglows will be accomplished by spectral discrimination of key emissions with a continuous night time operation of a spectrometer and photometers.

本研究有两个主要目的：1)主要目的是测量和研究格陵兰岛Sonderstrom高纬度观测站的声重力波（AGW）结构和进入中间层的通量。气辉图像结构的研究现在可以用来计算具有大垂直波长的AGWs携带的水平动量的垂直通量。气辉成像仪具有独特的测量能力，能够测量具有大相位速度（短周期）的agw，这些agw携带了中间层中波动量通量的主要部分。具体来说，将与在新墨西哥州阿尔伯克基（Albuquerque）、一个中低纬度站和南极站进行的类似测量进行比较。2)第二个目标是测量和研究与中间层中零星金属层有关的中间层排放。最近的研究表明，这些可能涉及高纬度层，并且可能与某些释放有关的化学加热。为了提取本征波测量值，对风进行多普勒校正是很重要的。目前，桑德斯特罗姆的流星雷达正在工作，它能够进行这种测量。瑞利激光雷达对平流层和中下层的结构进行常规的散射测量，纳激光雷达对中上层的结构进行常规的散射测量。激光雷达观测到的速度较慢的agw与气辉观测到的光谱相辅相成。这些数据将被吸收并用于：1)量化Sondrestrom波浪携带的水平动量和能量的垂直通量；2)与在Albuquerque低纬度地区收集的数据进行比较。高纬度地区的大气动力学和化学过程是独特的，特别是薄层和零星层现象。通过气辉化学发光发射的测量来解决这些事件中的化学过程是很重要的。气辉的常规测量将通过光谱仪和光度计连续夜间操作对关键发射进行光谱辨别来完成。