Interactions between Various Headlands, Beaches, and Dunes along the Coast of Ceará State, Northeast Brazil

The equatorial coast of NE Brazil consists of long and wide sandy beaches, segmented by rhythmic headlands, sometimes with seacliffs. Large and extensive mobile transgressive dunefields distribute up to 6 km landward of the coastline. The coastal area of Ceará state, as examined in this study by the means of measurements, field work, and remote sensing, illustrates a characteristic morphology composed of interactive headland, beach, and dune systems. Under persistent unidirectional wind and wave forcing, the morphodynamics of the studied coast is strongly controlled by the headlands because they produce an interruption of the longshore sand transport at their contact, resulting in accretion updrift of the headland and in erosion downdrift of the headland. The headland bypass dunefield activates one major mechanism and dynamics of the system headland-beach-dune because they refeed the beaches in the process of erosion downdrift. Littoral bypass is also an important process, supplying the cell with new sand, together with the erosion that takes place in the zetaform beach. Such a unique system can be strongly affected by anthropogenic activities, which can influence nearly all the factors at all temporal and spatial scales