Collaborative Studies of the Antarctic Mesosphere and Lower Thermosphere

中间层和低层热层（MLT）位于地球表面以上80 ~ 120公里的高度，是地面低层大气（对流层和平流层）与高层大气近地空间环境（热层和电离层）耦合的高度动态区域。在这个区域特别重要的是向上传播的热强迫大气潮汐和全球尺度的行星波。这两种现象都将热量和动量从低层大气输送到高层大气。近年来的研究表明，北极和南极MLT具有丰富的频谱波，可能比低层大气对全球变化更敏感。本研究的主要目标是观测、量化、模拟并进一步了解南极上空MLT环流的时空结构和变率及其与北极的共性。第二个目标是量化和了解通过流星消融而沉积到上层大气中的物质及其对当地和区域空气经济过程的影响。这包括流星通量、温度和动力学对南极上空钠的季节性分布的影响。流星雷达安装在南极阿蒙森-斯科特站，从2002年1月开始连续运行。一个新的钠夜光成像仪将安装在南极，以推断MLT中的钠丰度。该仪器的观测结果将与南极法布里-珀罗干涉仪的温度测量和流星雷达的风和流星通量测量相结合，以提高我们对钠化学和动力学的理解。这些观测将使用复杂的数值模式进行解释，并结合北极测量以及当前的线性和非线性大气模式进行解释，以促进目前对MLT区域重要过程的理解。这项研究也有助于培养和教育研究生和本科生，博士后和早期职业终身教职员工。

The mesosphere and lower thermosphere (MLT), at an altitude between 80 and 120 km above the Earth's surface, is a highly dynamic region that couples the lower terrestrial atmosphere (troposphere and stratosphere) with the upper atmosphere near-Earth space environment (thermosphere and ionosphere). Of particular importance in this region are both the upward propagating thermally forced atmospheric tides and global scale planetary waves. Both of these phenomena transport heat and momentum from the lower atmosphere into the upper atmosphere. Studies in recent years have indicated that the Arctic and Antarctic MLT possess a rich spectrum waves and may be more sensitive to global change than the lower atmosphere. The primary goal of this research is to observe, quantify, model, and further understand the spatial-temporal structure and variability of the MLT circulation above Antarctica and its commonalities with the Arctic. A secondary goal is to quantify and understand the deposition of mass into the upper atmosphere through the ablation of meteors and the resulting effect on local and regional aeronomic processes. This includes the effect of meteor flux, temperature and dynamics on the seasonal distribution of sodium over the South Pole. Meteor radar was installed at the South Pole Amundsen-Scott station and has been running continuously since January 2002. A new sodium nightglow imager will be installed at the South Pole to infer the sodium abundance in the MLT. Observations from this instrument will be combined with the South Pole Fabry-Perot interferometer temperature measurements and the meteor radar wind and meteor flux measurements to improve our understanding of the sodium chemistry and dynamics. These observations will be interpreted using sophisticated numerical models and interpreted in conjunction with Arctic measurements along with current linear and nonlinear atmospheric models to advance the current understanding of processes important to the MLT region. This research also contributes to the training and education of the graduate and undergraduate students, a postdoc and early career tenure track faculty.