The southern Brazilian coast, located between 29,5°S and 32°S, comprises a large coastal plain shaped by recent sea level fluctuations. The system developed and evolved after successive marine regressions and trangressions during the Quaternary, resulting in the sequential deposition of four barrier­lagoon depositional systems. The Patos­Mirim lagoon system is the largest South­American lagoon complex, including Brazilian and Uruguayan rivers. With water residence times estimated on 5 months (Patos) and 7 months (Mirim), the coastal lagoons work as reservoirs, supplying water for human consumption, agricultural production and industrial processes. Both lagoons are naturally connected by the São Gonçalo channel, and to the ocean through the Patos lagoon estuary, which exports large inputs of fresh, nutrient­rich waters to the coastal oceanic waters. This proposal requests TanDEM­X data of the southern Brazilian coastal plain, where is located the largest lagoon complex in South America. The data required will be used to perform the first simulations of such complex in a coupled fashion, including their surrounding wetlands. The study will combine numerical modeling and remote sensing data to represent the exchanges between the lagoons and their flood plains, allowing for addressing the impacts of reported climatic changes in the region. Complimentary, TanDEM­X data will be used to predict shoreline changes due to climatic changes in a sensitive coastal environment.(Proposal Number: DEM_HYDR1776)..