Simulação de elevação do nível do mar na praia do Leme - RJ.

Abstract

The increasing warnings about the weather changes and their consequences are a concern for society in general. Doubts are evolved about the real changes that might occur, mainly regarding the effects of the ocean mean sea level and their effects on coastal regions. Sometimes the broadcast information contribute to a limited perception of the spatio-temporal extent of phenomena. Analogously, the democratization of maps is ever-broadening, and does not constitute a tool just for professionals dealing with the field of Cartography and other Geosciences. This is one of the great benefits enabled by the Digital Cartography. However, it wouldn t have such a wide range without the association of this information to a powerful means of communication as the Web. The Internet is one of the most democratic means of communication in the world and a wide-range tool for society. This tool can be used yet to build knowledge, allowing individuals to understand a phenomenon more easily, by visualizing/simulating it in real time. That provides a better understanding for society to formulate opinion and points of view about the case in question. Based on this reasoning, this thesis has the purpose of simulating scenarios of mean sea level elevations and make them available in the form of interactive maps on the Web, using a Digital Elevation Model accurate enough. For that, Leme Beach, in the city of Rio de Janeiro, was chosen as study area. The process to reach the objectives involved phases of collecting survey data, devoloping an integrated database of pre-existing data, interpolations, simulations of scenarios of the sea level elevation and implementation of a webpage. The researched scenarios were obtained by simulating the sea level elevation every 0.5 m until 4.0 m above the current elevation number. The obtained results show that Leme Beach will undergo geomorphological changes, reducing up to 18.0 m of the beach extension, to a mean sea level elevation of 2.0 m. However, the seashore will suffer significant impacts from a sea level elevation of 3.0 m, by which the planimetric sea level rising can range between 76 and 90 m, what would affect the sidewalk and the outfall region of Leme rain waters respectively. This would result in an additional volume of water on the beach, of approximately 106.000 m3 and a loss of up to 41.400 m3 of sand. Only from 3.5 m of elevation the sea would reach Atlântica Avenue and, from that altitude on, the sea level rising would gradually trigger floods all over Leme neighborhood.