Intertidal finger bars at El Puntal spit, bay of Santander, Spain

Abstract

We indentify the presence of an intertidal finger bar system in the swell-protected beaches of El Puntal Spit (Bay of Santander, Spain). The Horus video monitoring system allows us to perform a 2 year survey (June 2008- June 2010). We found that the bar system persists during the survey period with a wavelength of about 25 m and an oblique orientation with respect to the shore. Moreover, the analysis of the position of a particular bar (Bar 10) shows a movement characterized by a net migration to the west and a faster oscillation to the east or the west. Preliminary climate data analysis and morphological model results show that tide seems to be a forcing in the motion of the bars but also wind and waves generated by the wind probably affects the bar dynamics.