Stratospheric warming effects on thermospheric O(1S) dayglow dynamics

This study examines the effect of a sudden stratospheric warming (SSW) on the thermosphere, and in particular the response of thermospheric O(1S) dayglow as a proxy for SSW‐induced variations in the atomic oxygen volume mixing ratio. Thermospheric O(1S) volume emission rates and temperatures observed by the WIND Imaging Interferometer on UARS in February 1993 at latitudes from 50°N to 70°N and from 90 km to 280 km height have shown a depletion above 140 km in the daytime O(1S) volume emission rates, which commenced around the onset of the SSW and lasted over a period of 3–4 days before returning to and exceeding the pre‐SSW values during the SSW recovery phase. Below 140 km height the effect was manifested by a fourfold enhancement in the O(1S) volume emission rate at ∼100 km, which correlated with the cold temperature anomaly of the SSW at and below the stratopause. Key Points The decrease of thermospheric atomic oxygen dayglow during stratospheric warming