Dynamics of Beaches and Dunes Dominated by Westerly Winds. Tres Arroyos and San Cayetano, Argentina

The beaches of San Cayetano and Tres Arroyos counties (Buenos Aires, Argentina) characterise by fine sand availability burying ancient cliffs. The sand ramps are conditioned to westerly winds, episodically affected by winds coming from the South. The comparison of ancient photographs and satellite images it was estimated retreating rates of 0,4 m/yr increasing slowly in the last years. Although the dominant winds were recorded form the N, at the beaches winds dominate from the WSW. Coastal dunes migrate at rates of 3-6 m/yr, conditioning the inlets of creeks. Beach profiles performed during the intervals 2004-2005 and 2018-2019 indicate that the major variability occur at the intertidal areas and at the sand ramps (transition between backshores and foredunes). This littoral-aeolian dynamics are conditioning the strategies of afforestation and urban sprawl at the seaside localities.