Currents in the
Kaštela Bay: empirical analysis
and results of a numerical model
BEG PAKLAR, Mira ZORE-ARMANDA and Vlado DADIĆ
of Oceanography and Fisheries,P.O.Box 500, 21000 Split, Croatia
Basic statistical analysis of all available current data from the
Kaštela Bay for a period between 1953 and 1990 shows the importance of the sirocco wind in generating the circulation of the
Bay. Strong episodes of sirocco
reverse the estuarine circulation in the Bay inlet. During sirocco episodes current polarisation in the
east-west direction is observed, with a downwind current in the surface layer
and the compensatory current in the deeper layers. In the Bay interior sirocco-induced surface currents turn to the right
of the wind direction under the influence of the CORIOLIS force. During strong wind periods the mean current
speeds in the Bay interior are almost half of those in the Bay inlet, pointing
to the importance of the wind-induced transports from the adjacent Brač Channel.
obtained basin-wide cyclonic circulation during bora wind is in agreement with the conclusions
of the salinity measurement analysis. Numerical results show the formation of
several cyclonic and anticyclonic gyres during sirocco, so at least in some parts of the basin theoretical results and
empirical findings stemming from the salinity distribution are in agreement.
Comparison of direct current measurements with the results of the numerical
model shows good agreement during sirocco episodes, whereas the agreement is lower during bora. Proper prediction of the wind-induced
currents demands detailed knowledge of the wind stress magnitude and direction
above the Kaštela Bay and of the density distribution in the sea.
Key words: Kaštela Bay, currents, bora, sirocco
back (contet of acta vol . 43(1); July 2002.)