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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. 

The eruption of the Hunga Tonga–Hunga Ha’apai volcano on 15 January 2022 offered a good opportunity to explore the early impacts of tropical volcanic eruptions on stratospheric composition. Balloon-borne observations near Réunion Island revealed the unprecedented amount of water vapor injected by the volcano. The enhanced stratospheric humidity, radiative cooling, and expanded aerosol surface area in the volcanic plume created the ideal conditions for swift ozone depletion of 5% in the tropical stratosphere in just 1 week. The decrease in hydrogen chloride by 0.4 parts per million by volume (ppbv) and the increase in chlorine monoxide by 0.4 ppbv provided compelling evidence for chlorine activation within the volcanic plume. This study enhances our understanding of the effect of this unusual volcanic eruption on stratospheric chemistry and provides insights into possible chemistry changes that may occur in a changing climate. 

Abstract A multi-agency succession of field campaigns was conducted in southeastern Texas during July 2021 through October 2022 to study the complex interactions of aerosols, clouds and air pollution in the coastal urban environment. As part of the Tracking Aerosol Convection interactions Experiment (TRACER), the TRACER- Air Quality (TAQ) campaign the Experiment of Sea Breeze Convection, Aerosols, Precipitation and Environment (ESCAPE) and the Convective Cloud Urban Boundary Layer Experiment (CUBE), a combination of ground-based supersites and mobile laboratories, shipborne measurements and aircraft-based instrumentation were deployed. These diverse platforms collected high-resolution data to characterize the aerosol microphysics and chemistry, cloud and precipitation micro- and macro-physical properties, environmental thermodynamics and air quality-relevant constituents that are being used in follow-on analysis and modeling activities. We present the overall deployment setups, a summary of the campaign conditions and a sampling of early research results related to: (a) aerosol precursors in the urban environment, (b) influences of local meteorology on air pollution, (c) detailed observations of the sea breeze circulation, (d) retrieved supersaturation in convective updrafts, (e) characterizing the convective updraft lifecycle, (f) variability in lightning characteristics of convective storms and (g) urban influences on surface energy fluxes. The work concludes with discussion of future research activities highlighted by the TRACER model-intercomparison project to explore the representation of aerosol-convective interactions in high-resolution simulations.