Variaciones de turbidez de las aguas de la bahía de Cádiz determinadas a partir del análisis de imágenes Landsat TM

Abstract

Landsat TM images has been analysed to obtain extent and direction data about turbidity flumes in several hydrodinamic sinoptic situations in Cadiz bay waters. Results are beside data from water samples. Five turbidity levels has been differentiated: very high turbidity, high, middle, low and very low, and three geographic sectors: a) Inner zone, closed to coast and with shoal waters of high and very high turbidity. This sector is very affected by littoral processes (tidals, surge and continental contribution); b) Middle zone, with middle and low turbidity waters, unafected by continent contributions and surge, although if by tidal ebb; c) Outer zone, with low and very low turbidity waters, little or nothing affected by coastal dynamic, except at moments of spring tides and great fluvial growings.

Study of analysed Landsat images demonstrates that for a point given, turbidity range variation is very big and depends of each hydrodynamic concrete situation, and is controled by same factor as: hydrodynamic system (tides, surge and currents), climate and meteorology, coast and sea bottom phisiography and continental contributions rates