CEDAR: The Role of Neutral Winds in the Day-to-day Variability of the Ionospheric Mid-Latitude Evening Anomalies

CEDAR：中性风在电离层中纬度夜间异常的日常变化中的作用

• 批准号: 1651461
• 负责人: Ludger Scherliess
• 金额: $ 16.24万
• 依托单位: Utah State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2021-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1651461&HistoricalAwards=false
• 关键词: CEDAR; Role; Neutral; Winds; Day

The Weddell Sea Anomaly (WSA) is a recurrent feature of the Southern hemisphere summertime midlatitude to high-latitude ionosphere. Electron densities maximize around the Weddell Sea region during the night, rather than during the day as would be expected due to photoionization by the Sun. The objective of the work is to understand the causes of these evening anomalies, with particular attention to the roles of thermospheric neutral winds, and waves originating from the lower atmosphere. Because winds are not directly sensed in this part of the atmosphere, they must be inferred from other available measurements such as electron density. A key value of the research is the generation and dissemination of observation-driven global-scale ionospheric winds computed from the PI's state of the art model.The WSA can be thought of as testbed for coupled ionosphere/thermosphere modeling capabilities. The primary research tool is USU's Thermospheric Wind Assimilation Model (TWAM) that will be coupled to an ionospheric assimilation system (GAIM). These two systems ingest data from a comprehensive set of ground-based and space-based data networks. They will enable investigation of the wind response to day-to-day variations in ionospheric drivers inside and outside the anomaly regions. This proposal is very well-aligned with the goals of the most recent Decadal Survey, which charges the thermospheric modeling and data assimilation communities with providing winds in data-absent regions.

Weddell Sea Anomaly（WSA）是南半球夏季中期到高纬度电离层的复发特征。电子密度在夜间在韦德尔海地区周围最大化，而不是在白天，因为太阳的光电离世。这项工作的目的是了解这些傍晚异常的原因，特别关注热层中性风的作用，而波源来自较低的大气层。由于在大气的这一部分没有直接感测风，因此必须从其他可用的测量值（例如电子密度）中推断出风。该研究的关键值是从PI的最先进模型计算出的观察驱动的全球尺度电离层风的产生和传播。可以将WSA视为耦合电离层/热层建模能力的测试。主要的研究工具是USU的热层风同化模型（TWAM），该模型将与电离层同化系统（GAIM）耦合。这两个系统从一组基于地面和空间数据网络的全面摄入数据。他们将对在异常区域内外的电离层驱动器的日常变化进行调查。该提案与最近的十年调查的目标非常吻合，该调查的目标为热圈建模和数据同化社区充电，并在数据吸收区域提供了风。