Automated Detection of Sea Breeze Circulations: A Climatology of Sea Breeze-Initiated Precipitation

The Delmarva Peninsula, located on the East Coast of the United States between the Chesapeake and Delaware Bays, experiences sea breeze circulations (SBC) regularly in the summer, with occasional convergence of multiple sea breeze fronts from the two Bays and adjoining Atlantic coastline. In some cases, there is enough uplift and convection related to the SBC that precipitation will form. Under certain conditions, the sea breeze front (SBF), which tends to be greater in vertical extent near the advancing edge of the SBC, is visible using radar reflectivity data. We introduce a state of the art detection method for objectively identifying and tracking the formation and movement of the Delmarva SBC. Reflectivity data from the KDOX NEXRAD station in Dover, Delaware are pre-processed to eliminate both ground clutter and precipitation by limiting acceptable values between 5-25 dBZ. A series of longitudinal transects are traversed step-wise from east to west to identify the SBF by detecting clusters of acceptable reflectivity values. We then develop a climatology of summer precipitation attributed to the SBC by associating the timing of precipitation events with the detection of a SBF. Characteristics of the SBC and associated precipitation events, such as precipitation intensity, spatial coverage, and inland penetration are presented. Results from this project will be used to inform a sensitivity study that will explore the impact of coastal urbanization and other land use and cover changes (LUCC) on the local summertime climate, in which SBC plays a central role.