电离层突发E层中的行星波及其他扰动

项目名称： 电离层突发E层中的行星波及其他扰动

项目编号： No.40804039

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 左小敏

作者单位： 中国地质大学（武汉）

项目金额： 15万元

中文摘要： 从20世纪中期50－60年代至今，电离层突发E层（Es）成为电离层研究的热点，它的出现具有偶发性，并难以预测，虽然公认的风剪切理论在解释Es的形成上取得了很大的成功，但是它也有一些不能解释的难题，近期研究表明除了风场之外，行星波、地磁活动、天气、地震等都有可能对Es层的形成产生影响。而其观测数据也对这些影响很敏感，比如某时段数据序列存在明显的行星波周期，和某天或某月参量的突然增大或减小的扰动现象。因此，我们有可能从Es的观测数据中提取到行星波或其他扰动信息。近年来Es与行星波的关系的研究也成为热点，Es的临界频率foEs数据序列中存在的行星波周期被很多学者证实。我们可以通过对遍布全球的电离层垂测台站的Es观测数据进行分析，提取行星波参量信息，以及其他扰动信息。同时对这些扰动的研究也有利于对Es形成的物理机制的进一步认识，并有助于解释夏季异常等难题。

中文关键词： 电离层突发E层；行星波；扰动

英文摘要： Midlatitude sporadic E (Es) layers, as thin plasma layers of enhanced metallic ion concentration that form frequently in the ionospheric E-region, have long been a topic of intensive research in the ionosphere physics since 1950s. The formation of the layers is well explained by the wind shear theory. However, several new results in the last decade suggest that the generation of Es is not yet fully understood. Recently, possible links between Es and atmospheric planetary waves (PW), geomagnetic activities, weather, earthquake and so on attracted considerable attention. Furthermore, the observation Es data was very sensitive to these effects, such as time sequences of Es occurrence marked planetary wave cycle, and a sudden increase or decrease of the Es parameters in the disturbances. So the PW oscillations or other disturbance informations may be extracted from the Es observation data. Recently many discussions have taken place surrounding the close relation between Es and PW and strong PW period oscillations in Es occurrence have been demonstrated by many scholars. We intend to use the Es data measured with a dense global network of digital ionosondes to calculate key PW parameters and other disturbance informations, then this can open a new avenue in the ongoing research of layering plasma phenomena in the E region and the physics of the interaction of ionospheric plasma with large-scale dynamics in the neutral atmosphere. On the other hand, researches on these disturbances suggest a new comprehension of the formation of Es and the well known but not well understood seasonal Es dependence.

英文关键词： Sporadic E layers;Planetary wave;disturbances