An Observational and Numerical Study of the Nocturnal Sea Breeze. Part I: Structure and Circulation

Abstract

Characteristics of inland-penetrating nocturnal sea breezes at the Savannah River Site (SRS) in South Carolina are discussed. Detailed observations from an area tower network during the Stable Boundary Layer Experiment (STABLE) indicate passage of marine air through SRS on three different nights. Large-scale winds are directed onshore for the first two nights, resulting in similar boundary layer structure and stability on these nights, while synoptic winds on the third night are offshore, leading to stronger convergence and wedging of the marine air under the inland air mass. The Regional Atmospheric Modeling System (RAMS) is used to simulate conditions for the final two nights. General features of the sea breeze are captured by the model, including wind shifts, moisture increases, turbulence structure differences between the two nights, and the formation of Kelvin–Helmholtz billows along the interface of marine and return airflow.