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Use of Terrestrial-LiDAR for quantifying morphological changes in PontaNegra Beach, Natal City, Northeast BrazilVenerando Eustáquio Amaro 1,2 , André Luís Silva Santos 2 , Ada Cristina Scudelari 3 & Bruno CésarPereira da Costa 21 Post-graduation Program in Geodynamic and Geophysics, Department of Geology, Federal University of Rio Grande do Norte,Natal, RN, 59.972-970, Brazilamaro@geologia.ufrn.br2 Post-graduation Program in Science and Petroleum Engineering, Federal University of Rio Grande do Norte, Natal, RN,59.972-970, Brazilalss10@gmail.com, brunocesarpc@hotmail.com3 Department of Civil Engineering, Federal University of Rio Grande do Norte, Natal, RN, 59.972-970, Brazilada@ct.ufrn.brAbstractThis paper describes and evaluates the latest applications of terrestrial-based Light Detection And Ranging (Li-DAR) surveying to monitor geomorphological changes on Ponta Negra Beach, Natal city, Rio Grande do NorteState (RN), extreme Northeastern Brazilian coast. The entire coastal zone of RN is controlled by dynamic factors ofhigh energy that cause widespread erosion/accretion and shoreline morphological intense instability. The intenseprocess of sediment transport is often cited among a variety of coastal effects caused by the interaction of manyocean-atmospheric factors and driving forces such as wind, waves, tides and currents, all of them affected by globalclimate changes impacts. In addition to these complex natural factors, the Ponta Negra Beach, as other sectors of theRN coast, has suffered intense anthropogenic pressure in recent decades. These combined factors led to hazards likethe disappearance of sand, destruction of the boardwalk and other seaside infrastructure, jeopardizing socioeconomicactivities.IntroductionPonta Negra Beach has been subject to accelerated erosion in recent decades and causes are often linked to thecoastal processes intensification of ocean-atmosphere interface, due to global climate change. Nevertheless, in recentdecades Natal city’s famed Ponta Negra beach also experienced an accelerating urban surface expansion andverticalization that have a significant potential impact in the beach and dune environments on which they occur.The climate on the Eastern littoral of RN, location of Natal city, is Tropical humid (Köppen-Geiger climate classificationAf) which differs from the driest climate on the inland. The climate unit of this geographic domain is alsoguaranteed by the high temperatures during the whole year and by the concentration of rainfall between Februaryand May. The annual average temperature was 26.2°C and the annual average precipitation was 1,724 mm/yearoccurring in Natal, according to measurements made obtained between 1992 and 2012. The Intertropical ConvergenceZone (ITCZ) strongly influences the climate on the Northeast Brazil through the Atlantic Ocean surface temperaturedistribution. In rainy years the ITCZ moves up to 06°S reaching the Northeast Brazil coast, remaining forlonger periods in the southern hemisphere until the month of May. General atmospheric circulation of NE Brazil isinfluenced continuously by the southeasterly dry air masses flow from the high pressure cell over the southern AtlanticOcean (McGregor and Nieuwolt, 1998). The study area is characterized by the trade winds pattern with strongSE component, varying seasonally between SSE and ESE. The highest wind speed for 2012 has been registeredbetween the months of July to October, with a variation of 9.0 m/s to 9.4 m/s and the smaller ones were around 4m/s coming from the South and observed in the first six months of the year. The continuous action of the tradewinds is responsible to promoting coastal drift and sediment transport northward. Likewise, this coastal zone is alsounder natural influence of waves and semidiurnal mesotidal regime.The current use of terrestrial LiDAR systems for studies of geomorphologic changes expanded widely and hassignificantly improved monitoring of short-term morphological processes in coastal areas. Many studies have used5