Feasibility Study to Develop a Large Aperture Lidar/Optical Facility for Observations of the Upper Atmosphere from 30-1000km

研究人员将研究广泛的科学原理，并为一个主要的新型激光雷达/光学设施制定详细的设计要求，以研究从平流层中部（约 30 公里）到热层（约 1000 公里）的地球大气层的化学和动力学。目标是确定当前挑战中高层大气科学界的关键科学问题，并确定哪些新的观测能力，特别是大孔径激光雷达系统，可以促进在解决这些问题方面取得重大进展。预计新激光雷达/光学设施的核心将是一个约 100 平方米的收集孔径，其中包括一个直径 3-4 米的完全可操纵望远镜以及大量较小的定点望远镜。此外，该设施还将包括重要的相关仪器，例如雷达、成像仪、光谱仪，或许还包括使用气球和火箭探测器的现场测量能力。具体项目目标是： 1. 确定当前挑战中层和高层大气群的关键科学问题（重点是那些可能受益于大孔径激光雷达/光学设施实现的测量的问题）， 2. 确定哪些新的观测能力可以促进在解决这些问题方面取得重大进展， 3. 制定将作为新天文台核心的大型光学望远镜的顶层设计和操作要求， 4. 确定激光雷达系统的设计和操作要求5. 确定对实现新天文台的全部潜力至关重要的关键相关仪器，以及 6. 确定该设施应位于何处，以便为科学做出最大贡献并确保最大的运营生产力。陆地高层大气研究的突出挑战是确定空间-大气相互作用区域的状态。 人们越来越认识到，来自低层大气的波能气象源是造成高层大气显着变化的原因。此外，源自磁层的高能粒子和场定期改变电离层的状态。这些影响通过电离层等离子体和中性热层气体之间的紧密耦合而汇聚，从而在空间-大气相互作用区域（SAIR）中产生涌现行为。为了充分探索 100 公里以上关键区域的中性离子耦合，需要对中性大气进行测量，以补充雷达对等离子体的观测。对中性热层风、温度和物种的激光雷达测量可以实现这些探索，这是高层大气科学界最优先考虑的目标。

The investigators will examine the broad scientific rationale and develop detailed design requirements for a major new lidar/optical facility to study the chemistry and dynamics of the Earth's atmosphere from the middle stratosphere (~30 km) to well into the thermosphere (~1000 km). The objectives are to identify the key scientific problems currently challenging the middle and upper atmospheric sciences communities and determine what new observational capabilities, especially large aperture lidar systems, could facilitate significant progress in addressing those problems. It is envisioned that the centerpiece of the new lidar/optical facility would be a ~100 square meter collecting aperture that would consist of a 3-4 meter diameter fully steerable telescope in combination with a large array of smaller fix-pointed telescopes. In addition the facility would include important correlative instruments such as radars, imagers, spectrometers and perhaps in situ measurement capabilities using balloon and rocket probes. The specific project objectives are: 1. To determine the key scientific problems currently challenging the middle and upper atmosphere communities (with emphasis on those problems that could potentially benefit from the measurements achievable by a large aperture lidar/optical facility), 2. To determine what new observational capabilities could facilitate significant progress in addressing those problems, 3. To develop the top level design and operational requirements for the large optical telescope that would serve as the centerpiece of the new observatory, 4. To determine the design and operational requirements for the lidar systems that would utilize the large telescope, 5. To determine the key correlative instrumentation that would be essential to realize the full potential of the new observatory, and 6. To determine where the facility should be located to make the greatest contribution to science and to insure maximum operating productivity. The outstanding challenge in terrestrial upper atmosphere research is specifying the state of the space-atmosphere interaction region. There is growing recognition that meteorological sources of wave energy from the lower atmosphere are responsible for producing significant variability in the upper atmosphere. Furthermore, energetic particles and fields originating from the magnetosphere regularly alter the state of the ionosphere. These influences converge through close coupling between the ionosphere plasma and neutral thermosphere gas to produce emergent behavior in the space-atmosphere interaction region (SAIR). To fully explore neutral-ion coupling in the critical region above 100 km requires measurements of the neutral atmosphere to complement radar observations of the plasma. Lidar measurements of neutral thermospheric winds, temperatures and species can enable these explorations, an objective of highest priority for the upper atmosphere science community.