M-I Coupling: A Model for Ionospheric Velocity Structure in the High-Latitude F Region

M-I耦合：高纬F区电离层速度结构模型

• 批准号: 0101118
• 负责人: Marc Hairston
• 金额: $ 21万
• 依托单位: University of Texas at Dallas
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2005-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0101118&HistoricalAwards=false
• 关键词: Coupling; Model; Ionospheric; Velocity; Structure

As coupled magnetospheric, ionospheric and thermospheric models mature it is increasingly apparent that Joule heating may take place over a wide variety of spatial scale sizes. Current models used for space weather estimate Joule heating rates by using average bulk plasma flow velocities (Vb) in large-scale high-latitude convection patterns. However, recent studies suggest that structure in the ion drift over smaller scale sizes of 10 to 100 km may change the estimated Joule heating rate by more than a factor of 2. This proposal will use data from the Dynamics Explorer-2 satellite and from the DMSP satellites to describe the average and maximum amplitude of velocity structure (AV) at high latitudes as a function of position, season, solar cycle and geomagnetic activity. Thus, Joule heating rates previously calculated using only the average bulk flow rate Vb of the plasma will be improved to become a function of Vb + AV. The data description will be cast in the form of a model that functionally describes the magnitude of the velocity structure in terms of the bulk flow so that these refined estimates of Joule heating rates can be easily used both in thermospheric models and as boundary conditions for coupling magnetospheric models with the ionosphere. A first order dependence of the model on magnetic activity will allow a better specification of the high latitude thermosphere and ionosphere for space weather applications.

随着磁层，电离层和热层模型的耦合，越来越明显的是，焦耳加热可能会在各种空间尺寸的大小上进行。当前用于空间天气估算的模型通过在大规模的高纬度对流模式下使用平均体积血浆流速度（VB）。然而，最近的研究表明，离子的结构在较小规模的10到100 km上漂移可能会使估计的焦耳加热率提高2倍以上。该建议将使用Dynamics Explorer-2卫星和从该数据中的数据。 DMSP卫星以高纬度的速度结构（AV）的平均幅度和最大幅度，这是位置，季节，太阳周期和地磁活动的函数。因此，先前仅使用血浆的平均体积流量Vb计算的焦耳加热率将改善成为VB + AV的函数。数据描述将以模型的形式施放，该模型在功能上以散装流量来描述速度结构的大小，以便在热层模型和作为耦合的边界条件中都可以轻松地使用这些焦耳加热速率的精制估计值具有电离层的磁层模型。该模型对磁性活动的一阶依赖性将使高纬度热层和电离层为太空天气应用提供更好的规格。