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Abstract Total solar eclipses (TSEs) are impressive astronomical events that have attracted people’s curiosity since ancient times. Their abrupt alterations to the radiation balance have stimulated studies on “eclipse meteorology,” most of them documenting events in the Northern Hemisphere while only one TSE (23 November 2003) has been described over Antarctica. On 4 December 2021—just a few days before the austral summer solstice—the moon blocked the sun over the austral high latitudes, with the path of totality arching from the Weddell Sea to the Amundsen Sea, thus producing a ∼2-min central TSE. In this work we present high-resolution meteorological observations from Union Glacier Camp (80°S, 83°W), the only location with a working station under totality, and South Pole station. These observations were complemented with meteorological records from 37 surface stations across Antarctica. Notably, the largest cooling (∼5°C) was observed over the East Antarctic dome, where obscurity was ∼85% while many sectors experienced insignificant temperature changes. This heterogenous cooling distribution, at odds with the seemingly homogeneous land surface of Antarctica, is partially captured by a simple radiative model. To further diagnose the effect of the eclipse on the surface meteorology, we ran multiple pairs of simulations (eclipse enabled and disabled) using the Weather Research and Forecasting (WRF) Model. The overall pattern and magnitude of the simulated cooling agree well with the observations and reveal that, in addition to the solar radiation deficit and cloud cover, low-level winds and the height of the planetary boundary layer are key determinants of the temperature changes and their spatial variability. 

Abstract Atmospheric gravity waves generated by an eclipse were first proposed in 1970. Despite numerous efforts since, there has been no definitive evidence for eclipse generated gravity waves in the lower to middle atmosphere. Measuring wave characteristics produced by a definite forcing event such as an eclipse provides crucial knowledge for developing more accurate physical descriptions of gravity waves. These waves are fundamental to the transport of energy and momentum throughout the atmosphere and their parameterization or simulation in numerical models provides increased accuracy to forecasts. Here, we present the findings from a radiosonde field campaign carried out during the total solar eclipse of July 2, 2019 aimed at detecting eclipse-driven gravity waves in the stratosphere. This eclipse was the source of three stratospheric gravity waves. The first wave (eclipse wave #1) was detected 156 min after totality and the other two waves were detected 53 and 62 min after totality (eclipse waves #2 and #3 respectively) using balloon-borne radiosondes. Our results demonstrate both the importance of field campaign design and the limitations of currently accepted balloon-borne analysis techniques for the detection of stratospheric gravity waves.