Variations of Low-latitude Thermospheric Winds and Temperature during
the 2020/2021 Major Sudden Stratospheric Warming as Observed by ICON and
GOLD Satellites
Abstract
Using ICON and GOLD satellite observations, the response of the
thermospheric daytime horizontal winds and neutral temperature to the
2020/2021 major sudden stratospheric warming (SSW) is studied at low- to
middle latitudes (0° - 40°N). Comparison with observations during the
non-SSW winter of 2019/2020 and the pre-SSW period (December 2020)
clearly demonstrates the SSW-induced changes. The northward and westward
thermospheric winds are enhanced during the warming event, while
temperature around 150 km drops by up about 50 K compared to the pre-SSW
phase. Changes in the horizontal circulation during the SSW can generate
upwelling at low-latitudes, which can contribute to the adiabatic
cooling of the low-latitude thermosphere. The observed changes during
the major SSW are a manifestation of long-range vertical coupling in the
atmosphere.