The index of ozone anomaly (IOA) has been proposed to detect changes in tropospheric ozone associated with strong earthquakes. The tropospheric ozone prior and after the 2008 Wenchuan earthquake has been analyzed using IOA. Atmospheric infrared sounder ozone volume mixing ratio (O3 VMR) at different pressure levels (600, 500, 400, 300, 200 hPa) for an 18-year period 2003–2020 has been considered to identify the unique behavior associated with the strong earthquakes. Our results show distinct enhancement in tropospheric ozone occurred 5 d (7 May 2008) prior to the main event and distributed along the Longmenshan fault zone. An enhancement in IOA has also been observed around the time of the 2013 Lushan and 2017 Jiuzhaigou earthquakes, but with the different emergence time, which indicates that the unusual behavior of tropospheric ozone depends on the tectonic and geological environment, focal mechanism, focal depth, meteorological conditions, and other factors. The location of increased tropospheric ozone indicates the epicenter of earthquakes. The magnitude of earthquake could be one of the important factors affecting the appearance of the anomalous tropospheric ozone. The possible mechanism for the increased tropospheric ozone associated with strong earthquakes is discussed in this article. The quasi-synchronous changes of tropospheric ozone and other parameters in the lithosphere/atmosphere/ionosphere have been found by combining with the other published results related to the Wenchuan earthquake, which show the existence of coupling during the earthquake preparation phase associated with the lithosphere–atmosphere–ionosphere coupling.

中文翻译：

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与强地震相关的对流层臭氧变化及其可能机制

臭氧异常指数 (IOA) 已被提议用于检测与强地震相关的对流层臭氧变化。使用 IOA 分析了 2008 年汶川地震前后的对流层臭氧。2003-2020 年 18 年期间不同压力水平（600、500、400、300、200 hPa）下的大气红外探测器臭氧体积混合比（O3 VMR）被认为是识别与强地震相关的独特行为。我们的结果表明，对流层臭氧在主事件发生前 5 天（2008 年 5 月 7 日）明显增强，并沿龙门山断裂带分布。在 2013 年庐山地震和 2017 年九寨沟地震前后也观察到了 IOA 的增强，但随着出现时间的不同，这表明对流层臭氧的异常行为取决于构造地质环境、震源机制、震源深度、气象条件等因素。对流层臭氧增加的位置表明地震的震中。地震的震级可能是影响对流层臭氧异常出现的重要因素之一。本文讨论了与强地震相关的对流层臭氧增加的可能机制。结合其他已发表的汶川地震相关成果，发现了岩石圈/大气/电离层对流层臭氧等参数的准同步变化，