Quantification of Seasonal and Solar Cycle Variations of the Ionospheric Electron Density

电离层电子密度的季节和太阳周期变化的量化

• 批准号: 9815108
• 负责人: Philip Richards
• 金额: $ 23.7万
• 依托单位: University of Alabama in Huntsville
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-05-01 至 2003-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9815108&HistoricalAwards=false
• 关键词: Quantification; Seasonal; Solar; Cycle; Variations

The primary objective of this study is to improve the capability of predicting ionospheric weather by improving the basic understanding of the climatology (long-term variations) of the F-region ionosphere. This objective will be accomplished through a detailed analysis of the seasonal and solar cycle variations of the ionospheric peak electron density (NmF2). Quantification of the reasons for the long term variations is a necessary prelude to solving the problem of predicting the day-to-day variability (weather). Of primary concern will be the determination of the dependence of observed NmF2 on both the daily and long-term solar activity indices (F10.7, F10.7A). Currently, this very basic relationship is not well known. The causes of the observed density variations will be explored with the aid of the theoretical ionosphere model, known as the FLIP model, which is capable of utilizing key ionospheric measurements as constraints. With the aid of a newly developed algorithm to adjust the model neutral densities, comparison of the observed and modeled electron density variations will enable the determination of the changes in the neutral densities or photoionization rates that may be required to reproduce the observations. This study will lead to improved forecasting of ionospheric behavior by determining the underlying physical causes of the main variations in ionospheric electron density.

这项研究的主要目的是通过增进对F区电离层气候学（长期变化）的基本了解，提高预测电离层天气的能力。 将通过详细分析电离层峰值电子密度（NmF2）的季节性和太阳周期变化来实现这一目标。 对长期变化原因的定量分析是解决逐日变化（天气）预测问题的必要前提。 主要关注的是确定观测到的NmF2对每日和长期太阳活动指数（F10.7，F10.7A）的依赖性。 目前，这种非常基本的关系并不为人所知。 将借助称为FLIP模型的电离层理论模型探讨观测到的密度变化的原因，该模型能够利用关键的电离层测量值作为制约因素。 借助一种新开发的算法来调整模型中性密度，比较观察到的和模拟的电子密度变化将能够确定中性密度或光电离率的变化，这可能是再现观察所需的。这项研究将通过确定电离层电子密度主要变化的基本物理原因，改进对电离层行为的预测。