The ionospheric Winter Anomaly (WA) is a phenomenon discovered almost 100 years ago. It can be defined as the situations in which over a given location the winter ionization level is larger than the summer ionization level, for approximately the same solar activity conditions. Along the decades, a lot of studies have been carried out and relevant theories have been formulated to explain this phenomenon, but some aspects of the nature and physical principles of the WA are still a matter of discussion. The first objective of this work was to introduce a new technique for studying the WA, at any given location over the Oceans, based on the 27-year series of altimeter (TOPEX, Jason1, Jason 2 and Jason3 satellites)-derived Total Electron Content (TEC) data.

The second objective of this work was to validate the new technique by presenting a comparative analysis between the results obtained with the new technique and those already published. This goal has been accomplished by studying the WA events over the 50°N and 50°S geographic parallels using the 27-year long altimeter data series. The results have indicated clear and systematic WA occurrences over the Northern Hemisphere and a more complex situation over the Southern Hemisphere, with two regions having different behaviors. These results are in full agreement with the findings published in relevant previous works.

The last objective of this work was to present some original findings related to WA events. Taking advantage of the new technique, it has been shown that the WA might be interpreted as a high solar activity period consequence of a yearly periodic phenomenon. This phenomenon is always present, also during low solar activity years, even when WA effects are not visible. During winters over the Southern Hemisphere, it systematically produces (at any solar activity level) low maximum TEC values in the (180°E–360°E) longitudinal region and high maximum TEC values in the (0°E–180°E) longitudinal sector. Precisely, this last sector matches with the well-known region over which WA events are observed for high solar activity.

电离层冬季异常（WA）是近 100 年前发现的一种现象。它可以定义为在大致相同的太阳活动条件下，在给定位置冬季电离水平大于夏季电离水平的情况。几十年来，已经进行了大量研究并制定了相关理论来解释这种现象，但是WA的性质和物理原理的某些方面仍然是讨论的问题。这项工作的第一个目标是基于 27 年系列的高度计（TOPEX、Jason1、Jason 2 和 Jason3 卫星）导出的总电子含量，引入一种新技术，用于研究海洋上任何给定位置的 WA (TEC) 数据。

这项工作的第二个目标是通过对新技术获得的结果与已发表的结果进行比较分析来验证新技术。该目标是通过使用 27 年长的高度计数据系列研究 50°N 和 50°S 地理平行线上的 WA 事件来实现的。结果表明，北半球发生了清晰而系统的 WA 事件，而南半球的情况更为复杂，两个地区的行为不同。这些结果与之前相关工作中发表的发现完全一致。

这项工作的最后一个目标是展示一些与西澳事件相关的原始发现。利用新技术，已经表明 WA 可能被解释为年度周期性现象的高太阳活动期结果。这种现象总是存在，即使在 WA 效应不可见的情况下，在太阳活动低的年份也是如此。在南半球的冬季，它系统地产生（在任何太阳活动水平）纵向区域 (180°E–360°E) 的低最大 TEC 值和 (0°E–180°E) 的高最大 TEC 值纵向部门。准确地说，最后一个扇区与众所周知的区域相匹配，在该区域上观察到西澳事件的高太阳活动。