Cross‐Shelf Penetrating Fronts of Buoyant Coastal Currents Around the Headland

Abstract

Estuarine water mixed with oceanic water moves along the coast as a buoyant coastal current, which usually follows isobaths if the coast is largely straight. A bottom-trapped river plume is thus often formed in which the bottom front stands at a specific location (Chapman & Lentz, 1994;Lentz & Helfrich, 2002). Hence, most of the buoyant current moves in the along-shelf rather than in the cross-shelf direction. Ideally, inside the river mouth different-sourced water mixes and exchanges (

Circulation and Retention of River Plumes Around Capes

“…Our finding that river plume separation increases with increasing Ro is consistent with those by Zhou and Wu (2023) who studied the ejection and separation of the Changjiang River plume at submarine headlands in the Yellow Sea. Their approach calculates the radius of curvature of an idealized headland with a curve fitting method.…”

“…Informed by the San Francisco Bay Plume, the model domain is designed to roughly resemble the U. S. west coast, with the land on the right-hand side and a cape in the far field of the plume. This setup is similar to that used by Zhou and Wu (2023), except the cape here is farther from the river outflow to focus on far-field plume dynamics. The domain is 125 km wide and 250 km long, distributed into 256 × 512 cells and 20 terrain-following vertical levels.…”

“…With satellite data and simulations, the study found that flow separation is facilitated by the tighter turning of the coastline relative to the inertial radius of the flow. Another recent study described the overshooting of a river plume into the Yellow Sea, where the exchange with deeper waters is modulated by submarine headlands (Zhou & Wu, 2023). The authors observed the separation patterns in surface salinity and chlorophyll data, emphasizing their implications for cross‐shelf exchange.…”