The present study investigates the ionospheric F-layer scintillation responses in the American sector (90°W–0°, ±50° dip latitude) during the Northern Hemisphere winter sudden stratospheric warming events of 2007–2008, 2008–2009, 2009–2010, and 2012–2013. The scintillation data used in this work are obtained from the radio occultation observations of the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) mission. The important results of this study are described as follows: the occurrence altitude and rate of ionospheric F-layer scintillation over the American sector decrease by an average of 13.48 km and 17%, respectively, during the sudden stratospheric warming (SSW) periods compared with the pre-SSW periods. We find that ionospheric F-layer scintillation over the American sector shows similar inhibitory responses to each SSW event, although these SSW events have diversities in some aspects, such as SSW types and solar and geomagnetic activities. To our knowledge, this study is the first to discover that an SSW event under low solar activity, including a minor warming event, can obviously affect the generation of ionospheric irregularities. Additionally, the types of SSW events may influence the decrease in altitude but not the occurrence rate. The decreased plasma vertical drift during prereversal enhancement, together with the changed meridional wind, are the possible mechanisms for the above results. In addition, we find that the enhanced planetary wave and lunar semidiurnal tide activities may be responsible for the decreases in the occurrence rate of ionospheric F-layer scintillation before the peak warming of the 2008–2009 and 2009–2010 SSW events.

中文翻译：

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平流层突然变暖事件期间美国部门电离层 F 层闪烁变化

本研究调查了 2007-2008、2008-2009、2009-2010 年北半球冬季平流层突然变暖事件期间美国部门（90°W-0°，±50°倾角）的电离层 F 层闪烁响应和 2012-2013 年。这项工作中使用的闪烁数据来自气象、电离层和气候星座观测系统 (COSMIC) 任务的无线电掩星观测。本研究的重要成果如下：在平流层突然变暖（SSW）期间，美国扇区电离层F层闪烁的发生高度和速率分别平均降低了13.48公里和17%。前 SSW 时期。我们发现美国扇区上的电离层 F 层闪烁对每个 SSW 事件显示出类似的抑制反应，尽管这些 SSW 事件在某些方面具有多样性，例如 SSW 类型以及太阳和地磁活动。据我们所知，这项研究首次发现低太阳活动下的 SSW 事件，包括轻微的变暖事件，可以明显影响电离层不规则性的产生。此外，SSW 事件的类型可能会影响高度的下降，但不会影响发生率。反转前增强过程中等离子体垂直漂移的减少，以及经向风的改变，是上述结果的可能机制。此外，