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Louisiana lost nearly 5,000 km2 of its coastal land area due to relative sea level rise (including local, regional, and global factors driving relative sea level change) since 1932, mirroring both the hazards associated with sea level rise and the time horizons of sea level rise impacts expected this century. This represents an opportunity to examine the relationship between long-term population changes and shoreline change. Based on detailed land change data for the period 1932–2010 and a small area population estimation technique for the period 1940–2010, we examine intra-parish population changes in relation to shoreline changes for the one million plus residents living in the ten coastal parishes of Louisiana. We find that since 1940, only two of the ten coastal parishes exhibited landward population movement, which we define as movement perpendicular to the shoreline, exceeding 1 km. Three parishes exhibited seaward population movement in excess of 1 km. Overall, we find very little net intra-parish landward population movement for the region. Our findings suggest that coastal Louisiana's historical population has not moved in concert with observed shoreline encroachment. We also find a potential tipping point related to population migration when a neighborhood loses at least 50% of its land area. Our findings suggest that this lack of landward population movement could be attributable to either localized adaptation strategies or migrations to other landward areas. [ABSTRACT FROM AUTHOR]

This study found an unusually large variation in the coastal sea level difference (SLD) in the southwestern Japan Sea from July to October 2013. The time and horizontal scales were about 4 months and 1000 km along the coast, respectively. During the exceptionally hot summer of 2013, strong monsoon winds blew through the Tsushima Straits into the southwestern Japan Sea, because the North Pacific High was located farther west than average. The southwesterly winds averaged 7 m s −1 parallel to the coast in July 2013, resulting in Ekman transport toward the coast. The most noticeable SLD was measured between Omijima and Mishima, normal to the 250 km rectilinear coastal line. The velocity of the first branch of the Tsushima Warm Current increased to about 50 cm s −1 between Omijima and Mishima from late July to early August. Although the SLD seemed to simultaneously increase and decrease along the Japanese coast with large time scale, the variation in coastal SLD propagated along the Japanese coast, reaching Niigata-nishi in the eastern Japan Sea. The propagation speed in the wide continental shelf of the southern Japan Sea was much higher than that in the narrow eastern shelf, which was consistent with the behavior of continental shelf waves. [ABSTRACT FROM AUTHOR]

Rising sea levels and increased storminess are expected to accelerate the erosion of soft-cliff coastlines, threatening coastal infrastructure and livelihoods. To develop predictive models of future coastal change we need fundamentally to know how rapidly coasts have been eroding in the past, and to understand the driving mechanisms of coastal change. Direct observations of cliff retreat rarely extend beyond 150 y, during which humans have significantly modified the coastal system. Cliff retreat rates are unknown in prior centuries and millennia. In this study, we derived retreat rates of chalk cliffs on the south coast of Great Britain over millennial time scales by coupling high-precision cosmogenic radionuclide geochronology and rigorous numerical modeling. Measured 10Be concentrations on rocky coastal platforms were compared with simulations of coastal evolution using a Monte Carlo approach to determine the most likely history of cliff retreat. The 10Be concentrations are consistent with retreat rates of chalk cliffs that were relatively slow (2-6 cm·y-1) until a few hundred years ago. Historical observations reveal that retreat rates have subsequently accelerated by an order of magnitude (22-32 cm·y-1). We suggest that acceleration is the result of thinning of cliff-front beaches, exacerbated by regional storminess and anthropogenic modification of the coast. [ABSTRACT FROM AUTHOR]

Cities are increasingly recognised as places in which climate change risks coalesce and from which climate change adaptation efforts are most likely to be mobilised. In an effort to reduce damages from storm surges and sea-level rise, the City of Cape Town municipal government set out to establish a coastal set-back line. This paper describes the process and highlights the potential for unanticipated conflict and resistance when notions of ‘best practice’ fail to consider local institutional interests and pre-existing legislation. This insight is important as coastal municipalities in South Africa look to implement set-back lines in compliance with the Integrated Coastal Management Act (Act 24 of 2008). McKenna et al. [McKenna, J., Cooper, A., & O'Hagan, A.M., Managing by principle: A critical analysis of the european principles of integrated coastal zone management (ICZM).Marine Policy, 32, 941–955. doi:10.1016/j.marpol.2008.02.005] elucidate the potential for conflicts and contradictions when applying the principles of Integrated Coastal Zone Management in Europe. Developing and a applying a set-back line for Cape Town's coastline was anticipated to be difficult given that the city remains socio-economically unequal and spatially segregated and that the coastline provides multiple different communities with amenities, resources and opportunities at the same time. What was not anticipated was the encountered resistance from within public sector directorates operating under the same policies. The paper suggests that differences in mentalities, technologies and resources (following Wood, J., and Shearing, C., (2007)Imagining security.Devon: Willan Publishing) make for subjective policy interpretations and applications by local officials. Recognising and managing these differences is critical if notions of ‘best practice’ prescribed at higher governance levels are to prove useful to climate change adaptation measures at the local scale. [ABSTRACT FROM PUBLISHER]

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. [ABSTRACT FROM AUTHOR]

The article offers information on the book "Understanding Sea-Level Rise and Variability," by John Church, Philip Woodworth, Thorkild Aarup, and Stan Wilson. It relates on the community adaption for sea level rise through the development of ice sheet and international ocean monitoring and modelling programs. Doctor John Church notes that by generating data, it can project global sea-level rise. He adds that populations in deltaic regions are at risk as sea-level changes the coastal fringes.