GIS Analysis of Global Impacts from Sea Level Rise

Future sea level rise caused by climate change would disrupt the physical processes, economic activities, and social systems in coastal regions. Based on a hypothetical global sea level increase of one to six meters, we developed GIS methods to assess and visualize the global impacts of potential inundation using the best available global datasets. After susceptible areas were delineated, we estimated that the size of the areas is between 1.055 (one meter) to 2.193 million km2 (six meters). Population in the susceptible areas was estimated to range from 108 (one meter) to 431 million (six meters) people. Among the seven land-cover types in the susceptible areas, forest and grassland account for more than 60 percent for all the increments of sea level rise. A suite of interactive visualization products was also developed to understand and communicate the ramifications of potential sea level rise. Introduction During the twentieth century, sea level has risen about 0.17 0.05 meters (IPCC, 2007). Without including the increased glacial output to the sea, the Intergovernmental Panel on Climate Change (IPCC) also estimated that the rate of sea level rise will roughly double during the next century due to increasing global temperature, with an upper range of sea level rise of 0.59 m by 2100. Church and White (2006) discovered a significant acceleration of sea level rise in the twentieth century and estimated a sea level rise from 2.0 to 3.4 meters between 1990 and 2100 if the acceleration PHOTOGRAMMETRIC ENGINEER ING & REMOTE SENS ING J u l y 2009 807 Xingong Li and David Braaten are at the University of Kansas, Department of Geography, 1475 Jayhawk Blvd., Lawrence, KS 66045 and the Center for Remote Sensing of Ice Sheets (CReSIS) ([email protected]). Rex J. Rowley is at Haskell Indian Nations University, College of Arts and Science, 155 Indian Avenue, Lawrence, KS 66046. John C. Kostelnick is at Illinois State University, Department of Geography-Geology, Campus Box 4400, Normal, IL 61790, and formerly at Haskell Indian Nations University, College of Arts and Science, Lawrence, KS 66046. Joshua Meisel is at the Center for Remote Sensing of Ice Sheets (CReSIS), and formerly at Haskell Indian Nations University, College of Arts and Science, Lawrence, KS 66046. Kalonie Hulbutta is at the United States Census Bureau, and formerly at Haskell Indian Nations University, College of Arts and Science, 155 Indian Avenue, Lawrence, KS 66046, and the Center for Remote Sensing of Ice Sheets (CReSIS). Photogrammetric Engineering & Remote Sensing Vol. 75, No. 7, July 2009, pp. 807–818. 0099-1112/09/7507–0807/$3.00/0 © 2009 American Society for Photogrammetry and Remote Sensing GIS Analysis of Global Impacts from Sea Level Rise Xingong Li, Rex J. Rowley, John C. Kostelnick, David Braaten, Joshua Meisel, and Kalonie Hulbutta remains constant. Nearly a quarter of the world’s population lives at elevations below 100 m from mean sea level and within 100 km from a coast (Nicholls and Small, 2002). Furthermore, coastal regions have the greatest concentration of economic activities (Nicholls and Tol, 2006). Flooding caused by sea level rise will likely disrupt the physical processes, economic activities, and social systems in the coastal regions. To assist policy makers as well as the general public in understanding the risks, a global analysis of the impacts posed by sea level rise is needed even though the impacts in specific regions are better known (Marbaix and Nicholls, 2007). Numerous assessments of present and future coastal impacts of sea level rise have been conducted at regional and local scales. Several studies have been conducted for the United States by individual researchers (Zhang et al., 2004; Boruff et al., 2005), the United States Geological Survey (USGS) (Thieler et al., 2000), and the U.S. Environmental Protection Agency (EPA) (Titus et al., 1991). Huang et al. (2004) examined the potential risk of tidal inundation due to future sea level rise in the Pearl River delta, China, and found that a large part of the delta plain will be vulnerable to tidal inundation with a sea level rise as small as 30 cm. Cooper et al. (2005) examined the potential impacts of sea level rise on the New Jersey coast and proposed a range of adaptation and mitigation possibilities. At a local scale, Wu et al. (2002) showed that sea level rise will increase considerably the vulnerability of Cape May County, New Jersey, to flood hazards by increasing the areas that are exposed to the highest flood risk. Hennecke et al. (2004) applied a GIS and two coastal behavior models to estimate the vulnerability of a 10 km segment of beach to sea level rise and/or coastal storms. Only a few researchers have studied the global impacts of sea level rise using GIS analysis and global datasets that are now readily available. Nicholls et al. (1999), Nicholls (2002 and 2004), and Nicholls and Tol (2006) examined the potential impacts of global sea level rise on coastal flooding. Their analyses are at the scale of coastal countries and are limited by the assumptions that the coastal country polygons have a constant slope and that the population distribution within the polygons is uniform. Weiss and Overpeck (2003) mapped susceptible areas globally but did not extend their analysis to examine the impacts of sea level rise on land-cover and population. Dasgupta et al. (2007) reported the impacts of sea level rises on 84 developing counties. The population data 807-818_07-094.qxd 16/6/09 1:15 PM Page 807