A Case Study of Thermospheric Exospheric Temperature Responses During the G‐Condition at Mohe and Beijing Stations

Abstract The G‐condition (NmF 2 ≤ NmF 1 ) was observed by ground‐based ionosondes at Mohe and Beijing during the geomagnetic storm occurred on 23 and 24 April 2023. We studied exospheric temperature (Tex) responses during the G‐condition. Tex was derived from electron density (Ne) profiles (∼150–200 km) by the method proposed by Li et al. (2023, https://doi.org/10.1029/2022ja030988 ). The retrieved Tex showed obvious enhancements, with relative deviation of ∼10%–35% and ∼3%–20% at Mohe and Beijing, respectively. Additionally, chemical reaction rate increased by ∼15%–100% and ∼13%–30%, and O/N 2 decreased by ∼17%–35% and ∼23%–30% at Mohe and Beijing, respectively. Under photochemical equilibrium assumption, peak Ne is inversely proportional to chemical reaction rate and proportional to O/N 2 . Increased chemical reaction rate and decreased O/N 2 indicate a decrease in peak Ne. Compared to the increased Tex, the relative enhancement in Tex is more significantly associated with the G‐condition, with relative deviation above ∼10% during the G‐condition.