CEDAR: All-Sky Mapping of E-Region Neutral Winds Above Poker Flat, Alaska

CEDAR：阿拉斯加 Poker Flat 上空 E 区中性风的全天空测绘

• 批准号: 0737618
• 负责人: Mark Conde
• 金额: $ 19.74万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0737618&HistoricalAwards=false
• 关键词: CEDAR; Sky; Mapping; Region; Neutral

This project will use ground-based optical remote sensing to obtain two-dimensional spatially resolved maps of horizontal neutral winds in Earth's night-time auroral E-region. The maps will be derived from Doppler shifts of the atomic oxygen auroral emission line at 557.7 nm. While several other ground and spaced-based techniques exist for measuring E-region winds, they are all difficult, and they do not duplicate the coverage and resolution that is anticipated in this project. The wind maps will cover a geographic region approximately 700 km in diameter, centered on Poker Flat, Alaska. This fully includes the E-region field of view of the National Science Foundation's new AMISR radar. Vertical coverage will span approximately 110 km to 140 km. With the mapping region resolved into 60 to 100 sub-fields, integration times for a single map will vary between one and five minutes, depending on signal levels, for typical uncertainties of a few meters per second. Doppler temperature maps will also be obtained with the same spatial and temporal resolution, with typical uncertainties of less than 10K. A number of scientific studies will be conducted. All depend on combining E-region wind maps with data from other instruments monitoring the same field of view, including the Poker Flat AMISR radar. Topics to be studied include the role of ion-neutral momentum coupling in E-region neutral dynamics at small ( 100 km) spatial scales, the role of horizontal transport in the evolution of storm-induced thermospheric composition perturbations, horizontal velocity perturbations due to gravity waves, the role of neutral winds in determining the partitioning of magnetospheric energy deposition between heating and bulk motion of the neutral atmosphere, and the relationship between horizontal divergence and vertical wind in the E- and F-regions. The project includes work to significantly upgrade the instrument's self-calibration capability with a 5-color helium neon laser, a new frequency stabilized laser, and an automated calibration source viewing system. In addition to CEDAR-specific science topics, a number of broader impacts are anticipated. A graduate student will be supported to participate in this research, whose work will be integral to all aspects of the project. With a major emphasis on optical calibration, this project has obvious relevance to the University of Alaska's 400-level undergraduate optics class - which is required for all physics majors. Aspects of both the optical design and the resulting calibration data will be incorporated into the students' laboratory and homework projects. The E-region wind mapping would add to the infrastructure of atmospheric science at a general level by demonstrating a new capability that other experimenters could exploit according to their research needs. More specifically, there is a high degree of synergy with two major existing NSF funded projects at Poker Flat: The AMISR radar and a tristatic array of three narrow-field Fabry-Perot spectrometers.

该项目将利用地面光学遥感技术获取地球夜间极光e区水平中性风的二维空间分辨率地图。这些图将由原子氧极光发射线在557.7 nm处的多普勒频移得到。虽然有其他几种基于地面和空间的技术可以测量e区域的风，但它们都很困难，而且它们的覆盖范围和分辨率都无法复制本项目所期望的。这些风图将覆盖一个直径约700公里的地理区域，以阿拉斯加的Poker Flat为中心。这完全包括了美国国家科学基金会新AMISR雷达的e区视野。垂直覆盖范围约为110公里至140公里。由于测绘区域被分解为60到100个子域，单个地图的整合时间将在1到5分钟之间变化，具体取决于信号水平，典型的不确定性为每秒几米。还将获得具有相同空间和时间分辨率的多普勒温度图，典型的不确定度小于10K。将进行一系列科学研究。所有这些都依赖于e区风图与其他仪器监测同一视场的数据相结合，包括Poker Flat AMISR雷达。要研究的主题包括小（100公里）空间尺度e区中性动力学中离子-中性动量耦合的作用，水平输送在风暴引起的热层成分扰动演变中的作用，重力波引起的水平速度扰动，中性风在确定中性大气加热和大块运动之间磁层能量沉积分配中的作用。E区和f区水平辐散与垂直风的关系。该项目包括使用一个5色氦氖激光器、一个新的频率稳定激光器和一个自动校准源观看系统来显著升级仪器的自校准能力。除了cedar特有的科学主题外，预计还会产生一些更广泛的影响。将支持一名研究生参与这项研究，其工作将成为项目各个方面的组成部分。由于该项目主要侧重于光学校准，因此与阿拉斯加大学400级本科光学课程（所有物理专业都必修）有着明显的相关性。光学设计的各个方面和由此产生的校准数据将被纳入学生的实验室和家庭作业项目。e -区域的风图通过展示一种新的能力，其他实验人员可以根据他们的研究需要加以利用，从而在一般水平上增加大气科学的基础设施。更具体地说，在Poker Flat有两个主要的国家科学基金会资助的项目：AMISR雷达和三个窄场Fabry-Perot光谱仪的三静力阵列。