Developing a Framework for Assessing Coastal Vulnerability to Sea Level Rise in Southern New England, USA

Abstract

Scientists predict that sea level rise will intensify wetland loss, saltwater intrusion, and the problems caused by waves, storm surges, and shoreline erosion (Nicholls et al., Trans R Soc 369:161–181, 2011). The ability to accurately identify low-lying lands is critical for assessing the vulnerability of coastal regions. To do this, coastal managers need elevation data and other coastal zone information, but these data are not always available at resolutions appropriate for making state and regional governance decisions on climate change and adaptation. Coastal Resilience (Ferdaña et al., Adapting to climate change: building interactive decision support to meet management objectives for coastal conservation and hazard mitigation on long island, New York, USA. In: Andrade Pérez A, Herrera Fernandez B, Cazzolla Gatti R (eds) Building resilience to climate change: ecosystem-based adaptation and lessons from the field. IUCN, Gland, 164 pp, 2010) is an ecosystem-based planning framework and web mapping application that visually displays ecological, socio-economic, and coastal hazards information to examine different adaptation solutions. This technical study highlights the limitations and opportunities of mapping sea level rise in Southern New England, USA, in order to evaluate coastal vulnerability and therefore appropriate adaptation strategies. We compared the accuracy of digital elevation data between a nationwide data set with a seamless, multi-state data set that incorporated local high-resolution data. Based on an independent accuracy assessment, the integrated elevation data approach using local- and regional-scale data was 55% (or 1.25 ft) more accurate than the national elevation data set alone. Results of this work indicate that regional elevation data sets are less accurate in determining different sea level rise scenarios than when integrating best-available local elevation data sets with regional data sets. With this approach, we can better assess the impacts of climate change to vulnerable low-lying lands and help communities identify adaptation plans that protect vulnerable coastal communities and ecosystems, allow for natural resource migration, and reduce socio-economic risk to coastal hazards.