Measurement of Total Eclipse Impact on Surface Layer Turbulence and Boundary Layer Structure

This study examines measurements of the atmospheric boundary layer response to rapid changes in surface forcing during the total solar eclipse of 8 April 2024 using coordinated surface, uncrewed aerial vehicle (UAV), and radiosonde observations. Measurements capture the evolution of the surface energy balance and associated changes in wind, temperature, humidity, and turbulence from the surface to 4000 m above ground level. The rapid reduction in solar radiation led to a collapse of buoyant turbulence production, followed by the formation of a shallow post-eclipse stable layer shortly after totality. This stable layer persisted for approximately 45 minutes and was maintained by surface heat loss through net longwave radiation and conduction into the soil. Its development strongly suppressed turbulence, producing reduced wind speeds and pronounced wind-direction rotation as near-surface flow decoupled from the air aloft, with turbulence decay observed both near the surface and within the surface layer. Suppressed vertical mixing reduced the transport of moisture and heat away from the surface and was accompanied by a temporary reduction in boundary layer height and the development of residual stratification aloft. These observations provide a detailed view of transient boundary layer collapse and recovery under extreme, short-duration radiative forcing.