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Abstract On 8 April 2024, a total solar eclipse overpassed Texas in the southern portion of the United States. To monitor the impact of the total solar eclipse, a group of students from Texas A&M University–Corpus Christi developed two weather balloon payloads and six ground-based instrument packages using microcontrollers and low-cost sensors. These instrument packages were deployed to six different sites spanning nearly 600 km along the total eclipse path from the Mexican border to North Texas. During the total eclipse, air temperature decreased, and relative humidity increased consistently at all six stations due to the reduction in sensible heating. The dewpoint temperatures decreased at the near surface at all sites likely due to the reduction in evaporation. Five of the six ground stations observed a slight dampening of the wind speed, and two of the six stations recorded significant counterclockwise wind shifts. No consistent pattern was observed in the surface vertical electric field at the six ground stations. The two balloon payloads captured the damping of the visible and ultraviolet (UV) radiation in the upper troposphere and lower stratosphere throughout the event. Though a slight decrease in both temperature and ozone in the lower stratosphere was observed after the totality, it is difficult to determine the impact from the eclipse on the ozone mixing ratio and dynamics in the lower stratosphere from only a few vertical profiles. For the students who participated, this field campaign has provided invaluable experiences in instrumentation, fieldwork, and data collection. 

Abstract This study examines the differences related to microphysical properties of ice in thunderstorms over the Amazon and Congo Basin using the Precipitation Feature (PF) data sets derived from passive microwave and radar observations from the Tropical Rainfall Measuring Mission and Global Precipitation Mission Core Satellites. Analysis reveals that Amazon thunderstorms are likely composed of ice crystals smaller but more numerous than those in the Congo Basin, resulting in half as many flashes per PF on average in the Amazon, for similar Ice Water Content (IWC) or Area of 30 dBZ at −10°C (A_charge). The increase of the flash count following an increase of the IWC (A_charge) is only 72% (61%) as effective in the Amazon as it would be in the Congo Basin area. PFs with similar 30 dBZ radar echo top heights exhibit lower Brightness Temperatures (TBs) in the 85/89, 165, and 183 GHz frequencies over the Amazon, indicating more numerous smaller ice particles compared to those over the Congo Basin, which tend to show colder TBs at 37 GHz, possibly due to more numerous large graupel or hail particles. Comparisons of TBs in PFs with similar 30 dBZ echo top temperature between the Amazon and 3 × 3º global grids show that the median TB in Amazon is higher than that in most oceanic areas but is comparable to areas having high oceanic lightning activity (e.g., South Pacific Convergence Zone). It suggests that systems in the Amazon have similarities with maritime precipitation systems, yet with distinct characteristics indicative of land systems. 

Abstract Convective gravity waves are important for the forcing of the quasi biennial oscillation (QBO). There is a wave component that is stationary with respect to the convective cells that is triggered by convection acting like a barrier to the background flow (moving mountain mechanism). Waves from this mechanism have only been observed in a few case studies and are not parameterized in climate models. However, the representation of the whole spectrum of gravity waves is crucial for the simulation of the QBO, especially in the lowermost stratosphere (below 50 hPa) where the QBO amplitudes are under‐estimated in current global circulation models. In this study, we present analysis of convective gravity wave observations from superpressure balloons in boreal winter 2019 and 2021, retrieving phase speeds, momentum fluxes, and drag. We also identify waves generated by the moving mountain mechanism using the theory of the Beres scheme as a basis. These waves do not have a specific period, but are of smaller horizontal scale, on average around 300 km, which is similar to the scale of convective systems. Our results show that gravity waves contribute up to 2/3 to the QBO forcing below 50 hPa and waves from the moving mountain mechanism are responsible for up to 10% of this forcing.