Coastal Impacts, Adaptation, and Vulnerabilities - Climate ...

72 Coastal Impacts, Adaptation, and VulnerabilitiesGalveston, TX and Mobile, AL found that 27 percent of major roads, 9 percent of raillines, and 72 percent of ports are at or below 122 centimeters. A 7-meter storm surge inthis area puts over half of the major highways, nearly half of the railways, 29 airports,and nearly all of the ports at risk of flooding (Savonis et al., 2008).Sea-level rise and an increase in the intensity of coastal storms could have substantialimpacts on U.S. port facilities (EPA, 2008; Moser et al., 2008; Savonis et al., 2008; US-GCRP, 2009). Major storms cause many types of damage to ports, including: direct damageto port infrastructure, release of hazardous materials stored on the port, loss of jobs,supply chain interruptions, downtime, debris on surrounding waterways and neighborhoods,damage to cargo, and others (Esteban et al., 2009; Fritz et al., 2008; Joint LegislativeCommittee on Performance Evaluation and Expenditure Review, 2006; Lewis et al.,2006; Louisiana Department of Transportation and Development Office of Public Worksand Intermodal Transportation, 2006; Reeve, 2010). Port shutdowns in Mississippi afterHurricane Katrina impacted commerce in 30 states (Joint Legislative Committee on PerformanceEvaluation and Expenditure Review, 2006).Hurricane Ike caused $2.4 billion of damage to Texas ports and waterways (FEMA,2008). Many ports may require modifications to berths and docks and associated infrastructureas sea level rises, though few ports have taken such actions yet (Becker et al.,2011). A few ports have begun to conduct assessments of their facilities to evaluate thekinds of impacts that may occur. Along the Gulf Coast, changes in sea levels and storminessare exacerbated by land subsidence, causing an even higher rate of relative rise.Due to the linked nature of ports with inland networks and climate-sensitive goods,they face a wide array of both direct and indirect threats (Stenek et al., 2011). A reportby the International Finance Corporation for The Port of Cartagena, Columbia (Steneket al., 2011) finds that ports are particularly vulnerable due to their long lifetimes andtheir reliance on an extensive global supply chain. Ports in different U.S. regions willface different types of issues due to local conditions and the types of products handled.In the New England area, Kirshen et al. (2008) project that, by 2050, the current 1-in-100year flooding event could become the 1-in-8 year event under the IPCC’s high-emissionsscenario, which would result in many more catastrophic events to critical port facilitiesalong this stretch of coast.Port managers in the Great Lakes are concerned that decreasing lake levels couldhave severe impacts on navigation (Becker et al., 2011). IPCC (2007) forecasts suggestdecreasing ice flows and increased snow fall in the winter months, which would resultin more significant seasonal fluctuations in lake levels. Lower lake levels would impactthe lake-shipping industry and could result in the cessation of shipping in very lowlake-level years.Climate change impacts on the coastal-shipping industry are less clear. Shippingroutes may need to be altered with changes in storm tracks and bridge clearances forlarge ships will be reduced as sea levels rise (Moser et al., 2008). Sea-level rise may resultin greater drafts in shipping channels, which would reduce dredging requirements insome areas; however, this could be offset by increased sediment loads along the coastresulting from increased precipitation and erosion from sea-level rise. Coastal stormscan have profound impacts on navigation channels. Wind- and precipitation-drivencurrents can cause channels to fill in and navigational aids such as buoys and channelmarkers can be driven off station. Marine debris such as tree limbs, damaged vessels, or