TEMPERATURE OF A SHALLOW LAGOON (SOLAR AND TIDAL CYCLE INTERACTION)

In this paper a shallow lagoon exchanging water with the sea and therm ally interacting with its bottom is considered. The tidal motion has b een assumed to be sinusoidal and the sea water has been assumed to be at the constant temperature T. Finally, assuming no horizontal therma l gradient (i.e. the water is always well mixed) and using simple assu mptions about the fluxes at the interfaces, the analytical solution of the system of equations is found (i.e. the temperature T(t) of the wa ter and the temperature T-s(z, t) of the sediment). The model reproduc es the qualitative thermal behaviour of a shallow lagoon such as that of Venice, where many experimental readings are available. In particul ar, it explains the main effect of the tide during winter, and the min or and perturbative effect (series of double peaks in the temperature trend) of the tide in the summer time.