Silva, R.; Martínez, M.L.; Hesp, P.; Catalan, P.; Osorio, A. F.; Martell, R.; Fossati, M.; Miot da Silva, G.; Mariño-Tapia, I.; Pereira, P.; Cienfuegos, R.; Klein, A., and Govaere, G., 2014. Present and future challenges of coastal erosion in Latin America.The coastal zones of Latin America have many landforms and environments, including sedimentary cliffs, deeply incised estuaries, headlands, barrier coasts and low lying, muddy coastal plains. These forms will respond differently to the expected changes in climate and associated sea level rise, which may produce coastal erosion in the future. Considering the coasts of Latin America overall, erosion is not yet a serious threat, although it is widespread and it is severe in some parts. Major erosion problems are frequently associated with human intervention in sediment supply, with poor planning or with the morphodynamic nature of the coast. Permanent erosional processes, locally or regionally, are caused by tectonic subsidence, deforestation and the fragmentation of coastal ecosystems, land use changes and sediment deficits because of infrastructure built along the coast. In this article we analyse coastal erosion in Latin America and the challenges it presents to the region. We first highlight the relevance of Latin America in terms of its biodiversity; then we describe the population at risk, demographic trends and economic growth throughout the low lying coastal zones. We also examine the vulnerability of the region by analyzing the resilience of key coastal ecosystems after exposure to the most frequent hazards that affect coastal zones in Latin America, namely tropical cyclones, sea level rise, ocean acidification, earthquakes and tsunamis. Finally, we discuss seven case studies of coastal erosion across Latin America. We close the study by pinpointing the main areas of concern in Latin America and explore possible strategies to overcome erosion and thus sustain economic growth, minimize population risk and maintain biodiversity.

This paper aims to highlight the prevailing experiences of Latin America and to clarify what 'green infrastructure' entails in addition to describing seven case studies from a range of coastal ecosystems (wetlands, coastal dunes, beaches and coral reefs) at scales varying from local to regional. The case studies are categorised according to their degree of naturalness (nature-based, engineered ecosystems, soft engineering, ecologically enhanced hard infrastructure and deengineering). Generally, the implementation of green infrastructure projects aims to increase resilience, enhance the provision of ecosystem services, recover biodiversity, reduce the negative effects of hard infrastructure and implement corrective measures. The greatest benefits of these projects relate to the creation of multi-functional spaces, which often combine the above advantages with improved opportunities for recreation and/or economic activities. It is hoped that this paper will disseminate the experience in green infrastructure among academics and practitioners and stimulate wider adoption of green infrastructure projects and good practices.

Change is inherent in coastal systems, which are amongst the most dynamic ones on Earth. Increasing anthropogenic pressure on coastal zones interferes with natural coastal dynamics and can cause ecosystem imbalances that render the zones less stable. Furthermore, human occupation of coastal zones often requires an uncharacteristic degree of stability for these inherently dynamic coastal systems. Coastal management teams face multifaceted challenges in protecting, rehabilitating and conserving coastal systems. Diverse monitoring schemes and modelling tools have been developed to address these challenges. In this article, we explore various perspectives: the integration of biophysical, ecological and social components; the uncertainties of diverse data sources; and the development of flexible coastal interventions. We propose general criteria and guidance for an Ecosystem-based Management (EbM) to coastal management, which aims primarily at adaptation to global change and uncertainties, and to managing and integrating social aspects and biophysical components based on the flows of energy and matter.

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Os processos de recuo da linha de costa em praias arenosas oceânicas estão comumente relacionados à ocorrência de marés de tempestade e agravados pelas construções sobre o limite superior de praia. Neste contexto, o trabalho apresentado quantificou a variabilidade da linha de costa de duas praias urbanizadas, Armação e Canasvieiras, situadas no sul do Brasil, que possuem orientações distintas ao clima de ondas, e relacionou sua exposição às marés de tempestade registradas entre os anos de 2009 e 2018. Para isso foram datadas e caracterizadas as marés de tempestade quanto às ondas, maré e ventos durante sua ocorrência. A variação da linha de costa foi calculada por meio do Método do Polígono de Mudança e do DSAS, que representam as variações a partir de modelos espaciais distintos. Os resultados mostram que houve recuo do limite superior nas duas praias e que o mesmo está relacionado às ocorrências de marés de tempestade. A praia da Armação apresentou recuo de até -4 m/ano e na praia de Canasvieiras registrou-se recuo de até -1m/ano. Constatou-se que na praia mais exposta, Armação, as marés de tempestade estão associadas às ondulações de SE e ventos de S. Por outro lado, os eventos na praia de Canasvieiras estão associados às ondulações de NE e ventos de N, tendo em ambas sido registrados durante as marés de sizígia. Nesta praia mais abrigada os eventos ocorrem sob condições meteo-oceanográficas particulares e podem igualmente causar impactos. Influence of beach orientation on shoreline retreat induced by storm surges: Armação and Canasvieiras, Ilha de Santa Catarina – SC A B S T R A C TCoastal retreat processes in oceanic sandy beaches are commonly related to storm surges and intensified by urbanization on the upper beach limit. In this research, shoreline variability was quantified in an interannual basis between 2009 and 2018 in two urbanized beaches in southern Brazil. Both Armação and Canasvieiras beaches have different orientations and exposures to the regional wave climate, but historically present severe wave-induced damage reports. The study was carried out based on the Change Polygon Method and the Digital Shoreline Analysis System (DSAS), two distinct shoreline change approaches based on different spatial models. The identified historical storm surges were discriminated according to waves, winds and tidal characteristics during their occurrence. It was concluded that the observed upper limit retreats in both beaches were, in fact, induced by storm surges. Due to its orientation, Armação beach is exposed to storm surges with SE waves and S winds. During the analyzed period, this beach showed a retreat up to -4 m/year. On the other hand, the events at Canasvieiras beach were associated with NE waves and N winds, showing a retreat up to -1 m/year. All the analyzed storm surge events occurred during spring tides and were concentrated in autumn. Although Armação beach is more exposed to storm surges due to its orientation, Canasvieiras beach, even with its sheltered shoreline orientation, can also be impacted depending on the storm surges characteristics.Keywords: Wave climate. The Change Polygon Method. Digital Shoreline Analysis System.