Analyzing the Motion of the Middle Atmosphere Using Nighttime RMR-lidar Observations at the Midlatitude Station Kühlungsborn (AMUN)

利用中纬度站 Kühlungsborn (AMUN) 的夜间 RMR 激光雷达观测分析中层大气的运动

• 批准号: 445400792
• 负责人: Dr. Michael Gerding
• 金额: --
• 依托单位: CoRA Office
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/445400792?language=en
• 关键词: Analyzing; Motion; Middle; Atmosphere; Using

Horizontal wind plays a key role in the dynamics of the atmosphere in general, and specifically for the propagation and dissipation of gravity waves and thermal tides. Simultaneous observations of winds and temperatures offer the unique possibility to retrieve both gravity wave kinetic and potential energy densities, being related by intrinsic wave properties. However, direct wind observations in the middle atmosphere are sparse especially between about 30 and 75 km, because neither radiosondes nor radars cover this altitude range. Wind radiometers or satellites do not provide wind information with sufficient accuracy and resolution for gravity wave investigations. Thus, we propose to set up a new lidar at Kühlungsborn/Germany (54°N, 12°E) to measure the horizontal wind by detecting the Doppler shift of Rayleigh backscatter using tilted telescopes. Beside climatological wind measurements, especially the propagation of inertia gravity waves in the middle atmosphere will be evaluated. We will calculate horizontal and vertical momentum fluxes and identify the altitudes of their deposition. These are crucial parameters for the energy budget of the atmosphere, and our results will provide a benchmark for general circulation models. Based on the wind data we will analyze hodographs to get intrinsic wave properties otherwise hidden for ground-based observers. We will separate the waves by vertical propagation direction and quantify the fraction of upward and downward propagating gravity waves, which requires local wind data to identify the Doppler shift of the wave’s phases. These analyses will deepen our understanding of the vertical coupling and of the underlying circulation in the middle atmosphere. This new wind lidar at Kühlungsborn complements a similar system operated by IAP in Northern Norway (ALOMAR, 69°N, 16°E). We will make use of the expertise developed for the ALOMAR lidar to reduce the design risks for the new lidar, and to foster wind measurements in the middle atmosphere as well as geophysical interpretation of the observations.

水平风在一般大气动力学中起着关键作用，特别是对于重力波和热潮汐的传播和消散。风和温度的同时观测提供了检索重力波动能密度和位能密度的独特可能性，这些密度与固有波性质相关。然而，中层大气中的直接风观测很少，特别是在大约30至75公里之间，因为无线电探空仪和雷达都没有覆盖这个高度范围。风辐射计或卫星不能提供足够精确和分辨率的风信息，用于重力波调查。因此，我们建议在德国Kühlungsborn（54 ° N，12 ° E）建立一个新的激光雷达，通过使用倾斜望远镜检测瑞利后向散射的多普勒频移来测量水平风。除了气候风的测量，特别是惯性重力波在中层大气中的传播将进行评估。我们将计算水平和垂直动量通量，并确定其沉积的高度。这些是大气能量收支的关键参数，我们的结果将为大气环流模型提供基准。基于风的数据，我们将分析速度图，以获得内在的波属性，否则隐藏的地面观测。我们将通过垂直传播方向分离波，并量化向上和向下传播的重力波的比例，这需要当地的风数据来识别波的相位的多普勒频移。这些分析将加深我们对垂直耦合和中层大气底层环流的理解。Kühlungsborn的这台新的风力激光雷达补充了IAP在挪威北方（ALOMAR，69 ° N，16 ° E）运行的类似系统。我们将利用为ALOMAR激光雷达开发的专业知识来降低新激光雷达的设计风险，并促进中层大气中的风测量以及对观测结果的地球物理解释。