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

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两年的中层大气动力学研究计划，该计划基于多普勒瑞利和拉曼激光雷达观测，并结合熊湖天文台(BLO)获得的其他光学测量和对风、密度、以及通过气球和火箭飞行获得的温度。(三个机构使用相同的文本提交了提案，但预算不同；UP将通过目前的NSF资金支持这一努力。)雪松的资金使得在犹他州安装了一个在UMD开发的、作为BLO设施一部分的ND：YAGRayleigh激光雷达系统成为可能。可能的高度覆盖范围已经扩展到75公里以上，增加了一个功率更大6倍的频率稳定的Nd：YAG激光器，该激光器是由CU购买的，用于激光雷达联盟系统。马里兰州激光雷达设施的这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，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--一个高分辨率法布里·佩罗标准具和一个双轴镜系统--这是测量后向散射瑞利和米氏激光雷达光谱的多普勒频移以观测中层大气视线风所必需的。将增加一个小型雷达系统，以观测中层大气的视线风。当任何飞机靠近波束时，将增加一个小型雷达系统来关闭激光发射器。在高压拉曼池中拉曼移位输出的基础上，将增加一条新的激光雷达传输通道(607 Nm)。在赠款的第二年开始时完成这些仪器改装后，应用新的多普勒激光雷达将利用532纳米处的米氏(微粒)散射和瑞利散射的激光回波，从10公里以上的大气晴空部分收集中层大气风和温度的垂直轮廓。这些剖面将为研究美国落基山脉链延伸山区上方中间大气中急流、行星波、潮汐和重力波的发生、结构、相互作用和变异性提供基础。这些波在中层大气中的倾斜传播被中层大气层的盛行风过滤，这将与BLO的几台仪器同时在中层顶区观测到的动力活动有关。将在激光雷达和气球和火箭的组合之间进行温度、密度和风的相关观测。PIS观测的一个副产品将是测量高云，特别是薄卷云中的气溶胶后向散射和消光，以及平流层气溶胶的探测。

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.