Science Serving Maryland's Coasts

Jenessa Duncombe, Wesleyan University

Class Year: 

Project Title: 

Wind-induced Lateral Circulation and Mixing in the Chesapeake Bay


The lateral salinity gradient responds to wind and tidal forcing in the Chesapeake Bay with spatial variation in salinity. The layers of isohalines tilt to the western shore during flood tide and slack before ebb tide, while the isohalines flatten during ebb and slack before flood tide, creating a semi-diurnal seesaw motion of the salinity gradient. The degree of the tilt correlates to the sensitivity of the tide to the Coriolis Effect, a phenomenon previously not well understood spatially. Sensitivity to wind forcing occurs on a more drastic scale and results in tilting to the Eastern shore. Up-welling and down-welling zones appear on the shallow shoals during wind events. The shallow shoals also experienced regularly changing salinity from 11-15 PSU within the interval of six hours. Both up-welling and down-welling zones and the seesaw motion of the salinity gradient may indicate lateral mixing.