On the possibility of convective overturning in the Słupsk Furrow overflow of the Baltic Sea

Abstract Closely spaced CTD transects across the Slupsk Furrow displayed a ‘downward- bending’ of salinity contours below the salinity interface on the southern flank due to a transverse circulation in the saline water overflow. Numerical simulation of a gravity current in an idealized channel with geometry, dimensions and initial density stratification all much the same as in the Slupsk Furrow was applied to verify whether the downward-bending could be transformed into an inverted density stratification. Some arguments in favour of the possibility of convective overturning due to the differential transverse advection beneath the gravity current, brought on by the numerical simulations, are discussed.