Collaborative Research: Lidar Studies of Middle Atmosperhic Dynamics (CEDAR)

合作研究：中大气动力学激光雷达研究 (CEDAR)

• 批准号: 9302118
• 负责人: Vincent Wickwar
• 金额: $ 10万
• 依托单位: Utah State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-08-01 至 1996-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9302118&HistoricalAwards=false
• 关键词: Collaborative; Research; Lidar; Studies; Middle

A lidar consortium consisting of Clemson University (CU), Utah State University (USU), the University of Maryland (UMD), and the University of Pittsburgh (UP) jointly propose a 2-year research program on middle atmosphere dynamics based on Doppler Rayleigh and Raman lidar observations combined with other optical measurements obtained at Bear Lake Observatory (BLO) and measurements of winds, densities, and temperatures obtained from balloon and rocket flights. (Proposals have been submitted by three institutions using the same text, but different budgets; UP will support this effort through current NSF funding.) CEDAR funding made possible the installation in Utah of a Nd:YAG Rayleigh lidar system that had been developed at UMD and moved to USU to be part of the BLO facilities. The possible altitude coverage has been extended upward to 75 km with the addition of a 6 times more powerful frequency-stable Nd:YAG laser that was purchased by CU for use with the lidar Consortium system. This upgrade of the Maryland lidar facility also includes one additional detector channel, which is a Raman 607 nm channel that extends profile observations of temperature structure downward to the ground from 30 km. The first year of this proposed effort would continue observations of components - a high-resolution Fabry Perot etalon and a double-axis mirror system - that are necessary for measuring the Doppler shift of the backscattered Rayleigh and Mie lidar spectra to observe line-of-sight winds in the middle atmosphere. A small radar system will be added to observe line-of-sight winds in the middle atmosphere. A small radar system will be added to shut off the laser transmitter when any aircraft is near the beam. A new lidar transmission channel will be added (607 nm) based on Raman-shifting the Nd laser output in a high pressure Raman cell. Upon completion of these instrumental modifications at the beginning of the second year of the grant award, application of the new Doppler lidar would collect vertical profiles of middle atmosphere winds and temperature from clear-air portions of the atmosphere above 10 km by using the laser returns from Mie (particulate) scattering and Rayleigh scattering at 532 nm. These profiles will provide the basis for examining the occurrence, structure, interaction, and variability of the jet stream, planetary waves, tides, and gravity waves in the middle atmosphere above the extended mountainous region of the American Rocky Mountain chain. The oblique propagation of these waves through the middle atmosphere as filtered by the prevailing winds in the middle atmosphere will be related to the dynamic activity simultaneously observed in the mesopause region by several instruments at BLO. Correlative observations of temperature, density, and winds will be made between the lidar and a combination of balloons and rockets. A by- product of the PIs observations will be the measurement of aerosol backscatter and extinction in high clouds, particularly thin cirrus, and the detection of stratospheric aerosols.

由克莱姆森大学 (CU)、犹他州立大学 (USU)、马里兰大学 (UMD) 和匹兹堡大学 (UP) 组成的激光雷达联盟联合提出了一项为期 2 年的基于多普勒瑞利的中层大气动力学研究计划拉曼激光雷达观测结果与熊湖天文台 (BLO) 获得的其他光学测量结果以及气球和火箭飞行获得的风、密度和温度测量结果相结合。 （三个机构已提交提案，使用相同的文本，但预算不同；UP 将通过当前 NSF 资金支持这项工作。）CEDAR 资金使得在犹他州安装 UMD 开发的 Nd:YAG 瑞利激光雷达系统成为可能并搬到 USU，成为 BLO 设施的一部分。 通过增加 6 倍强大的频率稳定 Nd:YAG 激光器（CU 购买用于激光雷达联盟系统），可能的高度覆盖范围已扩大到 75 公里。 马里兰州激光雷达设施的此次升级还包括一个额外的探测器通道，这是一个拉曼 607 nm 通道，可将温度结构的剖面观测从 30 公里向下延伸到地面。 这项拟议工作的第一年将继续观测组件——高分辨率法布里珀罗标准具和双轴反射镜系统——这些组件是测量反向散射瑞利和米氏激光雷达光谱的多普勒频移以观察线状激光雷达所必需的。视线风吹在中间的大气层中。 将添加一个小型雷达系统来观察中层大气中的视距风。 当任何飞机靠近光束时，将添加一个小型雷达系统来关闭激光发射器。 基于高压拉曼单元中 Nd 激光输出的拉曼位移，将添加一个新的激光雷达传输通道 (607 nm)。 在拨款的第二年年初完成这些仪器修改后，新的多普勒激光雷达的应用将通过使用激光返回从 10 公里以上大气层的晴空部分收集中层大气风和温度的垂直剖面。来自 532 nm 处的米氏（颗粒）散射和瑞利散射。 这些剖面将为研究美国落基山脉延伸山区上方中层大气中急流、行星波、潮汐和重力波的发生、结构、相互作用和变化提供基础。 这些波通过中层大气的倾斜传播，经中层大气盛行风的过滤，将与 BLO 的多个仪器在中层顶区域同时观测到的动态活动有关。 激光雷达与气球和火箭的组合将进行温度、密度和风的相关观测。 PI观测的副产品将是测量高云（特别是薄卷云）中的气溶胶反向散射和消光，以及平流层气溶胶的检测。