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

9302128 Meriwether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，结合贝尔湖天文台（BLO）获得的其他光学测量数据，以及从气球和火箭飞行中获得的风、密度和温度测量数据。（三个机构提交的提案使用相同的文本，但预算不同；UP将通过当前的NSF资金支持这项工作。）CEDAR的资金使得在犹他州安装Nd:YAG Rayleigh激光雷达系统成为可能，该系统是在UMD开发的，并转移到USU作为BLO设施的一部分。可能的高度覆盖范围已经扩展到75公里，增加了6倍强大的频率稳定Nd:YAG激光器，该激光器由CU购买用于激光雷达联盟系统。马里兰激光雷达设施的升级还包括一个额外的探测器通道，这是一个拉曼607纳米通道，将温度结构的剖面观测从30公里向下延伸到地面。这项计划的第一年将继续观测组件——一个高分辨率的法布里·佩罗标准子和一个双轴反射镜系统——这是测量后向散射瑞利和米激光雷达光谱的多普勒频移以观测中间大气中的视距风所必需的。将增加一个小型雷达系统，以观察大气层中部的视距风。当任何飞机靠近光束时，将增加一个小型雷达系统来关闭激光发射器。在高压拉曼电池中，基于拉曼位移的Nd激光输出将增加一个新的激光雷达传输通道（607 nm）。在拨款第二年开始完成这些仪器修改后，新的多普勒激光雷达的应用将利用532 nm的Mie（颗粒）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剖面。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的急流、行星波、潮汐和重力波的发生、结构、相互作用和可变性提供基础。这些波经中层大气盛行风过滤后在中层大气中的斜向传播，将与BLO若干仪器同时观测到的中层顶区域的动力活动有关。在激光雷达与气球和火箭的组合之间，将进行温度、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，以及探测平流层气溶胶。＊＊＊

9302128 Meriwether 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, a pplication 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. ***