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This lectures is based on a paper that describes the overpassing process using a case study from SE Brazil. A transgressive dunefield extends across a headland from Santinho beach to Ingleses beach. Analysis of precipitation data (1951-2014), wind direction and speed (1964-2014), aeolian drift potential, aerial photographs/satellite images (between 1938 and 2014) and morphological data (2002, 2010 and 2014) enable an analysis of decadal-scale dunefield evolution. The rainfall analysis shows an increasing trend that prompts a decrease in drift potential and sediment transport into the dunefield, and favors dune stabilization by vegetation growth. Superimposed on this long-term trend is a decadal cycle of sediment inputs to the system. The northern sector of Santinho beach has a positive sediment budget and provides about 6,000m³/year of sediment to the foredune. This then migrates into the dunefield and about 3,000-5,000m³/year arrives at Ingleses via overpassing. The remainder augments the dune volume.