Characterizing Changes of Atmospheric Gas and Particle Composition During the April 8, 2024 Total Solar Eclipse

Solar eclipses affect the amount of radiation to the Earth’s atmosphere, impacting photochemical reactions, atmospheric dynamics, and pollution dissipation. Observing the changes of atmospheric pollutants during solar eclipses also serves as a natural experiment to quantify the effects of photochemical reactions in pollution production and removal. The sudden change in UV light levels reduces or shuts down many UV light-dependent chemical reactions, leading to a diversion of several key pollutants from a normal sunny day trend. However, such a phenomenon is particularly difficult to characterize research due to the scarcity and unique circumstances of an eclipse, the short duration of a solar eclipse, and the range of chemical reactions taking place.

In this study, we used a variety of Kestrel devices (DROP and 5400 Heat Stress Tracker), and QuantAQ MODULAIRs to measure the surface level composition at three unique sites across North and Central Texas. We aimed to study the changes of atmosphere conditions throughout the progression of a total solar eclipse and the concentrations of surface-level pollutants due to variations in solar radiation and atmospheric dynamics.

Our results show that an increase in NO2 by 200% and a decrease in NO by 85% and O3 by 33% were observed during the eclipse. Wind speeds experienced an explicit decrease of 95% when totality was occurring at our locations. This led to a very significant decrease in the dispersion of NO2, NO, and O3 at all three of our sites.

In conclusion, with the rise in NO2 observed during the eclipse, we can expect this increasing trend to continue if there were a solar blockage for a longer period, causing negative repercussions and uncommon behaviors in pollutants. The work found in this study can be used to show the impacts of UV-obstructing chemicals on objects such as clouds and future eclipses, which can also be used to strengthen chemical models.