The long term response of a plume associated with freshwater penetration intoambient, ocean water under upwelling favorable winds is studied using the RegionalOcean Modeling System (ROMS) in an idealized domain. Three different cases wereexamined, including a shore perpendicular source and shore parallel source with steadywinds, and a shore perpendicular source with oscillating alongshore winds.Freshwater flux is used to define plume penetration. Alongshore penetration ofbuoyant currents is proportional to freshwater input and inversely proportional toupwelling wind stress strength. Strong wind more quickly prevents fresh water?spenetration.Under upwelling favorable winds, the plume is advected offshore by Ekmantransport as well as upcoast by the mean flow. This causes the bulge to detach from thecoast and move to upcoast and offshore with a 45 degree angle. The path of the bulge isroughly linear, and is independent of wind strength. The bulge speed has a linearrelationship with the wind stress strength, and it matches the expected speed based onEkman theory.Sinusoidal wind leads to sequential upwelling and downwelling events. The plumehas an asymmetric response to upwelling and downwelling and fresh water flux is changed immediately by wind. During downwelling, the downcoast fresh water transportis greatest, while it is reduced during upwelling. Background mean flow in thedowncoast direction substantially increases alongshore freshwater transport.
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