High‐latitude ionospheric convection models derived from Defense Meteorological Satellite Program ion drift observations and parameterized by the interplanetary magnetic field strength and direction
High‐latitude ionospheric convection models derived from Defense Meteorological Satellite Program ion drift observations and parameterized by the interplanetary magnetic field strength and direction
复制标题
高纬度电离层对流模型源自国防气象卫星计划离子漂移观测，并通过行星际磁场强度和方向进行参数化
DOI：
10.1029/2001ja000264
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发表时间：
2002
影响因子：
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通讯作者：
["V. Papitashvili
中科院分区：
文献类型：
--
作者：
["V. Papitashvili
利用国防气象卫星计划（DMSP）的热离子漂移测量，建立了一系列新的高纬电离层对流模型。该模型是通过将交叉极帽静电电位分类到磁纬度/磁局部时间桶中得到的。然后对每个仓中的电位进行回归分析，以确定三个季节（夏季、冬季和春分）与行星际磁场（IMF）的关系。电离层电动力学（LIMIE）的线性建模公式给出了对平均太阳风（即“准粘性”相互作用）和IMF By、Bz≤0和Bz >分量变化的对流响应。模拟的对流是前两个参数的叠加，其中IMF Bz≤0或Bz >分量。将回归分析结果拟合为球谐函数，建立了一个全局模型。得到的基于dmsp的电离层对流模型（DICM）完全被IMF的强度和方向参数化。有了这个模型，在安静到温和的地磁条件下，任何IMF配置都可以产生电离层对流模式。我们将DICM模式与其他可用的由IMF组织的高纬度对流模式进行了比较。DICM的新元素是它的准粘性和独立的国际货币基金组织依赖于南北两极地区的术语，这在其他电离层对流研究中没有明确发现。DICM的季节依赖性和半球间对称/不对称特征表明，夏季交叉极势比冬季低10-15%。后者符合场向电流的季节依赖性，也符合磁层-电离层耦合所需的电压-电流关系。
[1] A series of new high-latitude ionospheric convection models have been constructed using Defense Meteorological Satellite Program (DMSP) thermal ion drift measurements. The models are obtained by sorting cross polar cap electrostatic potentials into magnetic latitude/magnetic local time bins. A regression analysis of the potentials in each bin is then implemented for establishing the relationships to the interplanetary magnetic field (IMF) for three seasons: summer, winter, and equinox. A linear modeling formula for the ionospheric electrodynamics (LIMIE) yields a convection response to the average solar wind (i.e., the “quasi-viscous” interaction) and to changes in the IMF By, Bz ≤ 0, and Bz > 0 components. The modeled convection is a superposition of the first two parameters with either the IMF Bz ≤ 0 or the Bz > 0 component. A global model is created by fitting the regression analysis results to a spherical harmonic function. The resulting DMSP-based ionospheric convection model (DICM) is fully parameterized by the IMF strength and direction. With this model, ionospheric convection patterns can be generated for any IMF configuration during quiet to moderate geomagnetic conditions. We compare the DICM model with other available high-latitude convection patterns organized by the IMF. The new elements in DICM are its quasi-viscous and separate IMF-dependent terms for both the northern and southern polar regions, which are not explicitly found in other ionospheric convection studies. The DICM's seasonal dependence and interhemispheric symmetry/asymmetry features show that the summer cross-polar potentials are 10–15% smaller than the winter potentials. The latter is in agreement with the seasonal dependence of field-aligned currents and with the voltage-current relationship required for the proper magnetosphere-ionosphere coupling.