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.

威德尔海异常（WSA）是南半球夏季中高纬电离层的一个周期性特征。威德尔海附近的电子密度在夜间达到最大值，而不是像预期的那样在白天，这是由于太阳的光电离。这项工作的目的是了解这些夜间异常的原因，特别注意热层中性风和来自低层大气的波的作用。由于风在这部分大气中不能被直接感知，它们必须从其他可用的测量数据（如电子密度）中推断出来。该研究的一个关键价值是根据PI的最新模型计算出的观测驱动的全球尺度电离层风的生成和传播。WSA可以被认为是电离层/热层耦合建模能力的测试平台。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。这两个系统从一套全面的地基和天基数据网络获取数据。它们将有助于调查风对异常区域内外电离层驱动因素日常变化的反应。该提案与最近的十年调查的目标非常一致，该调查要求热层建模和数据同化社区提供缺乏数据地区的风。