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We investigate the climatology of Martian ionospheric disturbances using Mars Atmosphere and Volatile Evolution missioN (MAVEN) data in 2014–2023. The disturbance strength is estimated by calculating residuals of in situ O2+ ${{\mathrm{O}}_{2}}^{+}$ density from its large‐scale (filter window size ∼560 km) background and normalizing the residual with the background, as has been commonly used in terrestrial aeronomy. The disturbances are statistically stronger (a) in the local winter hemisphere than in summer and (b) on the nightside than on the dayside, with stark contrast across the terminator. The disturbances are more intense over the regions with strong radial magnetic fields (i.e., Martian crustal anomaly) than at unmagnetized regions, especially during the nighttime. Day‐to‐day variability of the Martian ionospheric disturbances does not exhibit a strong correlation with those of thermospheric CO2 disturbances or solar wind electron density/temperature at Mars. Plain Language Summary: Planet Mars hosts an atmosphere as the Earth does, of which the atoms and molecules at high altitudes are apt to be broken up into positive ions and electrons by sunlight or high‐energy particles passing around Mars. The resultant ionosphere, which is composed of charged particles, induces magnetic fields to protect the Martian surface and lower atmosphere from direct invasion of the solar wind. As is the case for the Earth, the Martian ionosphere is inhomogeneous, and the disturbances can be potential risk factors for direct/relayed communication between Martian surface facilities (e.g., rovers) and the Earth. This study presents an extensive climatology of the generic Martian ionospheric disturbances using the Mars Atmosphere and Volatile EvolutioN (MAVEN) satellite data obtained from 2014 to 2023, the longest in situ data set ever used for this subject. The results indicate that the disturbances generally favor the local winter hemisphere (than the local summer), nighttime (than daytime), and crustal magnetic anomaly (than non‐magnetized regions). Besides, the climatology of the disturbances cannot be well predicted by (a) the strength of thermospheric neutral disturbances at similar altitudes to the Martian ionosphere or (b) electron density/temperature of solar wind surrounding Mars. Key Points: Martian ionospheric disturbances on both the dayside and nightside prefer the local winter hemisphereNightside disturbances are stronger than dayside ones with strong contrast across the terminators (solar zenith angle ∼ 90°)Neither Martian thermospheric disturbances nor solar wind electrons exhibit a strong correlation with ionospheric disturbances [ABSTRACT FROM AUTHOR]

The purpose of this work is to investigate the responses of multiple parameters to the Madoi earthquake preparation. A new method is employed to extract anomalies in a geomagnetic field. The results show that there were abnormal changes in the lithosphere, atmosphere, and ionosphere near the epicenter before the earthquake. Despite the differences in spatial and temporal resolutions, the increase in geomagnetic residuals in the lithosphere exhibits similar temporal characteristics to the enhancement of thermal infrared radiation in the atmosphere. Two high–value regions are present in the ground–based geomagnetic high residuals and the ionospheric disturbances. The northern one is around the epicenter of the Madoi earthquake. Near the southern one, an M6.4 Yangbi earthquake occurred four hours before the Madoi earthquake. In this study, we have observed almost all of the physical phenomena that can occur during the preparation of an earthquake, as predicted using the electrostatic channel model. It can be inferred that the electrostatic channel is a possible mechanism for coupling between the lithosphere, atmosphere, and ionosphere during the Madoi earthquake. [ABSTRACT FROM AUTHOR]