The topside ionosphere accounts for a dominant part of the ionospheric total electron content, whereas accurate global modeling of topside ionospheric electron density (Ne) profile has not been fully achieved. In this study, a high precision Ne profile model, named α‐Chapman Based Electron Density Profile Model (α‐Chapman‐Based‐EDP), was built by using ∼4.5 million Ne profiles from the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC‐1) radio occultations. We first describe each of the profiles using five parameters of the α‐Chapman function, that is, peak density (NmF2) and height (hmF2) of F2 layer, scale height (Hm) as well as its altitude change rates, and then built a model for each of the parameters as a function of latitude, longitude, month, local time, and solar activity, through Empirical orthogonal function (EOF) analysis and Fourier expansion. Combining all the five models, we construct the α‐Chapman‐Based‐EDP. Compared with observations from COSMIC‐1 and ‐2, the model captures the ionospheric climatology well, such as solar activity dependence, seasonal variation, and spatial pattern, including the equatorial ionization anomaly and midlatitude trough as well as their variabilities. Our model can describe nearly 80% variability of Ne in F region. In contrast, the IRI2016 cannot well reproduce these characteristics, with errors higher than our model. The potential applications of our model were also discussed. A dense matrix data calculated by the model will be released in https://www.researchgate.net/profile/Qiaoling_Li5 with the permissions of COSMIC organizations.

中文翻译：

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基于COSMIC测量的F区电离层电子密度分布的全局经验模型。

顶面电离层占电离层总电子含量的主要部分，而顶面电离层电子密度（Ne）轮廓的精确全局建模尚未完全实现。在这项研究中，使用来自气象，电离层和水文星座星座观测系统的约450万个Ne剖面，建立了一个高精度的Ne剖面模型，称为基于α-查普曼的电子密度剖面模型（α-Chapman-Based-EDP）。气候（COSMIC-1）无线电掩星。我们首先使用α的五个参数来描述每个轮廓-查普曼函数，即F2层的峰密度（NmF2）和高度（hmF2），标尺高度（Hm）及其高度变化率，然后针对每个参数建立一个模型作为纬度函数，通过经验正交函数（EOF）分析和傅里叶展开来确定经度，月份，当地时间和太阳活动。结合所有五个模型，我们构建了基于α-查普曼的EDP。与COSMIC-1和‐2的观测结果相比，该模型很好地捕获了电离层气候，例如太阳活动依赖性，季节变化和空间格局，包括赤道电离异常和中纬度谷及其变化。我们的模型可以描述F区Ne的近80％的变异性。相反，IRI2016无法很好地重现这些特征，其误差高于我们的模型。还讨论了我们模型的潜在应用。该模型计算出的密集矩阵数据将在COSMIC组织的许可下在https://www.researchgate.net/profile/Qiaoling_Li5中发布。