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11 th International Symposium for GIS and Computer Cartography for Coastal Zones Managementwas 26.2°C and the annual average precipitation was 1,724 mm/year according to meteorological series for 1992 to2012, with rainfall concentrated between February and May. The rainy season is related to seasonal migration of theIntertropical Convergence Zone (ITCZ) and occurs only when it moves over Northeast Brazil. Trade winds patternis remarkably controlling strong SE trend component, varying seasonally between SSE and ESE. Ponta Negra Beachis exposed to locally generated wind-waves that may develop considerable erosive power when driven by northeasterlyor southeasterly winds (average 5.0 to 9.0 m/s). The highest wind speed for 2012 has been registered betweenthe months of July to October, with a variation of 9 m/s to 9.4 m/s. Tidal regime is of mesotidal semidiurnal type.The continuous action of the trade winds, tides and wave climate are responsible to promoting coastal drift andtransport of sediment northward parallel to the shoreline. Therefore, concerning the morphodynamic issue thiscoastal region is mostly wave-dominated and with continental shelf morphology contributes to sediment circulationalongshore (Testa and Bosence, 1998).Comprehension of coastal physical processes driving coastal erosion is crucial to establish an effective mitigationplan, particularly in urban beach areas used to recreational and touristic purposes and where seaside infrastructure,such as boardwalks, kiosks and even hotels are facing damage risk. Assessment of beach erosion/accretion behaviorbased on multisource remote sensing images and systematic approaches to analysis and interpretation represents arelevant strategy in getting information about the spatial and temporal evolution of the shoreline. Database integrationthrough Geographic Information Systems (GIS) promotes the understanding and quantification of erosion/accretionrate on interdecadal to interannual scenarios (Crowel et al. 1991). This strategy allows the improvementof prognostic models of future shoreline position, based on multisource data of various spatial and temporalresolutions, essential to coastal planning and management. Similarly, allows appropriate decisions regarding criteriato demarcate a setback area in the littoral, defines coastal erosion risk areas and subsidize decisions about appropriateinterventions for coastal protection.Further implication of this document was to develop a systematic methodology for attempting to identify and analyze:(i) quantifying shoreline offsets (sectors of main erosion/accretion rates); (ii) transport of sediment in crossshoreand alongshore direction; (iii) influence of runoff from the pluvial drainage system to erosion of beach face;(iv) erosion rate in some segments of Ponta Negra Beach based on coastal erosion maps for interdecadal and interannualscales; (v) the prognostic of Ponta Negra Beach in the context of embayed plan shape geometry.MethodsThe methods used in this study followed detailed aspects discussed in some previous references (e.g. Fletcher etal., 2003; Souto et al., 2006; Batista et al., 2009; Amaro et al., 2012) regarding mainly multitemporal mapping ofshorelines changes, considering geometric corrections to reduce distortions caused by the curvature of the Earth,refraction, sensor motion and terrain relief, as well as atmospheric corrections. These procedures allow to feasibledetection of shoreline changes and also the improvement of visual contrast between the surface features.Interdecadal analysis from 1973 to 2012 used moderate resolution (80 m, 30 m and 23.5 m) imaging sensorsLandsat 1-MSS, Landsat 5-TM, Landsat 7-ETM and IRS-6-LISS-3. High-resolution images from Ikonos-2, Quick-Bird and WorldWiew-2 (spatial resolutions of 1.0 m, 2.0 m and 60cm, respectively) were applied to interannualanalysis from 2003 to 2011. Accurate ground control points controlled by geodetic positioning and leveling wereused to orthorectify the whole images dataset. The second-order polynomial transformation was applied to georeferenceimages and accepted root mean square was less than 1. The procedure allowed a standardization of the multisourceimages, and thus comparison of shoreline changes from 1973 to 2012 (Figure 1). Remote sensing imageswere selected according to tide heights that in study area have an average of 1.1 m and maximum amplitude around0.3 m between two distinct dates. In order to undoubtedly detect of shoreline in moderate-resolution images a cubicpixel resampling were applied with increasing contrast of 70% that aided to delineate exactly the wet/dry line.Assessment of damage severity to seaside facilities due to erosion were based on indicators used to specify the intensityof destruction to sidewalks, manholes and kiosks, presented as Moderate (blue line), Strong (yellow line) andVery Strong (red line) on a map of coastal erosion from 1973 to 2012. The results were compared to multitemporalerosion behavior of the shoreline from 1973 to 2012 as a reference for discussions about coastal erosion.11