Collaborative Research: Expanded Correlative Dynamics and Meteor Studies Using the Southern Argentina Agile MEteor Radar

该奖项的研究将继续支持阿根廷南部敏捷MEteor雷达（SAAMER）系统的持续运作，但使用来自其他两个机构（波士顿大学和德国大气物理研究所）的研究同事安装的两个新的相关仪器的数据，具有多样化和显著扩展的研究应用。SAAMER被安装在火地岛上，以观测75至95公里高度范围内中间层和低热层的大规模动态。 这个高度范围是半日潮和各种行星波产生各种影响的地方。 这个位置是在一个纬度带内，这些运动有很大的响应，但也在现有的MLT数据库的风和温度是相当稀疏。SAAMER在TdF上的位置也是由地球上以南安第斯山脉、德雷克海峡和南极半岛为中心的重力波（GW）活动的主要“热点”的发生所激发的。这一热点是由于该地区的主要GW源，其中包括高山，强急流，和强大的锋面系统的通过。这些来源产生大GW事件和显着的MLT动量通量（MF）。 GW结构与MLT区域的大尺度运动的强相互作用是可以预期的，迄今为止的SAAMER结果证实了这一区域的通量将非常大的预期。这项工作还揭示了一种能力，以确定流星头部回波，非镜面流星尾迹，流星辐射在常规测量模式观察。 新的SAAMER研究将比以前更全面，因为相关的气辉成像以及新的本地瑞利激光雷达和多接收器雷达测量，结合使用SABER对TIMED和CIPS对AIM的卫星观测进行大规模和小规模动力学研究。这些多仪器研究将能够量化波长约为20-100公里的重要小规模全球Ws（和MF），如果没有这种相关测量，这些全球Ws（和MF）很难量化。MLT动力学研究，特别是在GW动力学，动量传输及其沉积的量化方面，是在全球研究，天气预报和气候模型中定义这些动力学的更准确参数化的核心需求，以满足广泛的社会需求。对大尺度动力学的测量同样有助于限制这些动力学的模型，特别是在南半球高纬度地区。流星体轨迹研究可为潜在的流星撞击风险提供线索。SAAMER也是一个教育和培训工具，通过各种NSF计划致力于促进美国和美国之间的国际合作活动。美国研究人员和学生，包括美国之间的广泛交流，PI的研究奖将涉及MLT动力学，流星和微观物理学，重点关注以下问题：1）继续对平均风，潮汐和PW及其结构，相互作用，半球间和年际变化进行大尺度动力学研究; 2）利用SAAMER、BU全天空成像仪和IAP瑞利激光雷达进一步量化小规模全球Ws的动量通量，通过对GW源及其传播特征的探索，结合对GW二次生成可能性的研究，以及平均风、潮汐和PW的影响; 3）进一步确定流星体群、速度、轨迹、流星率的日变、季节变和全球变，流星头部回波和非镜面尾迹和PMSE的常规测量，允许研究流星消融和PMSE微观物理。

The research for this award would renew the support for the ongoing operations of the Southern Argentina Agile MEteor Radar (SAAMER) system but with diverse and significantly expanded research applications using data from two new correlative instruments to be installed by research colleagues from two other institutions (Boston University and Institute for Atmospheric Physics, Germany). SAAMER was installed on Tierra del Fuego (TdF) to observe the large-scale dynamics within the mesosphere and lower thermosphere (MLT) in the altitude range of 75 to 95 km. This height range is where the semidiurnal tide and various planetary waves have a range of diverse effects. This location is within a latitude band where these motions have large responses, but also where the existing MLT database of winds and temperatures is quite sparse. The SAAMER location on TdF was also motivated by the occurrence of the major 'hotspot' of gravity wave (GW) activity on Earth centered over the Southern Andes, Drake Passage, and Antarctic Peninsula. This hotspot is due to the major GW sources in this region, which include high mountains, strong jet streams, and the passage of vigorous frontal systems. These sources yield large GW events and significant MLT momentum fluxes (MF). Strong interactions of GW structures with the larger-scale motions in the MLT region are to be expected, and SAAMER results to date confirm expectations that the fluxes in this region would be very large. This work has also revealed an ability to characterize meteor head echoes, non-specular meteor trails, and meteor radiants observed in routine measurement modes. The new SAAMER studies would be more comprehensive than before due to correlative airglow imaging as well as new local Rayleigh lidar and multi-receiver radar measurements combined with the use of satellite observations by SABER on TIMED and CIPS on AIM for large- and small-scale dynamics studies. These multi-instrument studies will enable quantification of the important small-scale GWs (and MFs) having wavelengths ëh~20-100 km that are challenging to quantify without such correlative measurements. MLT dynamical studies, especially in regard to the quantification of GW dynamics, momentum transport and its deposition, are central needs in defining more accurate parameterizations of these dynamics in global research, weather prediction, and climate models addressing broad societal needs. Measurements of large-scale dynamics likewise serve to constrain models of these dynamics, especially at high southern latitudes. Meteoroid trajectory studies may provide clues to potential meteor impact risks. SAAMER is also an educational and training tool through various NSF programs devoted to promoting international collaborative activities between U.S. and S. American researchers and students, including extensive exchanges between the U.S., Argentina, and Brazil to date.The research award to the PI would address MLT dynamics, meteors, and microphysics with focus upon the following questions:1) Continued Large-scale dynamics studies of mean winds, tides, and PWs and their structure, interactions, and inter-hemispheric and inter-annual variability;2) Further quantification of momentum fluxes by small-scale GWs employing SAAMER, the BU all-sky imager, and the IAP Rayleigh lidar, with exploration of GW sources and their propagation characteristics combined with the study of possible development of secondary GW generation, and influences by mean winds, tides, and PWs;3) Further characterization of the meteoroid population, velocities, trajectories, diurnal, seasonal, and global variability of meteor rates, and the meteoric mass flux into the MLT; and4) Routine measurements of meteor head echoes and non-specular trails and PMSE allowing studies addressing meteor ablation and PMSE microphysics.