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The air temperature changes in the Palu MW7.5 earthquake in Indonesia on 28 September 2018 were analyzed, based on the additive tectonic stress caused by celestial tidal-generating forces (ATSCTF) and air temperature data from the National Center for Environmental Prediction (NCEP). This paper explored the variation characteristics of three-dimensional stratified of air temperature caused by seismic activity and the coupling relationship between air temperature changes and the tidal force. The background information for air temperature calculation was obtained from the tidal force changes, and the air temperature increment method was used to study the temperature evolution process of different periods in the study area. The results found that the tidal force acting on the critical state earthquake faults may be an important external factor inducing earthquakes, and there was indeed a significant air temperature increase anomaly during the Palu MW7.5 earthquake. The paper also summarized the abnormal characteristics of air temperature caused by seismic activity: the air temperature closer to the land's surface has greater anomaly amplitude and a wider anomaly area than that of the upper air. [ABSTRACT FROM AUTHOR]

• The 2008 M w 7.9 Wenchuan earthquake decoupled most of the Longmenshan Fault Zone (LFZ). • Subsequent coupling & relocking is analysed using GPS & cross-fault levelling data. • The northeastern section of the LFZ has recovered coupled state. • Part of the middle section of the LFZ began relocking after the Lushan earthquake. • Strong coupling & high seismic risk continue in two aftershock gaps of the LFZ. The analysis of post-seismic fault relocking and healing is crucial for predicting future seismic risk in seismogenic regions. In this study, we investigated the dynamic characteristics of the coupling fraction and relocking process of the Longmenshan Fault Zone (LFZ) following the 2008 M w 7.9 Wenchuan earthquake. Analysis was performed using Global Positioning System (GPS) velocity data for the periods 2009–2011, 2011–2013, 2013–2015, and 2015–2018, combined with cross-fault levelling data from 2008 to 2017. The results show that following short-term creep caused by the Wenchuan earthquake, the northeastern section of the LFZ rapidly began relocking process, and that today, the fault plane is close to being fully coupled; following the subsequent 2013 M w 6.6 Lushan earthquake, coupling fraction along part of the middle section of the LFZ, southwest of the Wenchuan earthquake source, gradually increased, which are basically consistent with fault healing results indicated by permeability and seismic wave velocity. The Wenchuan earthquake also accelerated strain accumulation rates and enhanced coupling along the southwestern section of the LFZ. Following the Lushan earthquake, only local areas of the southwestern section were decoupled, limiting the release of accumulated strain energy. The aftershock gap between the Wenchuan and Lushan earthquakes, and the aftershock gap southwest of the Lushan earthquake remain strongly coupled and continue to accumulate strain energy; as such, seismic risk remains high in these two segments. [ABSTRACT FROM AUTHOR]