Abstract: Foredunes are highly dynamic coastal features that are intrinsically connected with their adjacent beaches. Correlations among parameters representative of aeolian and marine dynamics and the size and location of foredunes were carried out. The results indicate that foredune steady-state location depends mainly on marine dynamics, given that foredune toe level was positively correlated with the total water level of 10-year return period, which guarantees that the foredune is only eroded by waves occasionally and therefore will have time to recover and return to its long-term morphological state. Foredune steady-state size was characterized by its volume, which was positively correlated with aeolian sediment drift potential and exponentially related to the total water level with a 10-year return period. Aeolian sediment drift potential is indicative of the total amount of sand that potentially reaches the foredune, and therefore the foredune size is directly related to it. Higher total water level with a 10-year return period leads to a foredune located further from the shoreline and at a higher altitude (higher toe level as mentioned above). Consequently the beach is wider and the presence of moisture is expected to be lower. This wider and dryer beach allows the aeolian sediment transport to approximate to its maximum value, increasing its potential to build a bigger foredune. Data confirmed that the total water level with a 10-year return period and the foredune volume are exponentially related. The correlations found show that foredune steady-state size is related to both aeolian sediment drift potential and marine dynamics. Based on these results, a long-term conceptual model is proposed to explain the different morphological characteristics of the steady-state shape of foredunes as a function of the joint action of marine and wind dynamics.

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