Climate and Water Resources in the Carolinas: Approaches to Applying Global Climate Change Information to Local Decisions

A wide range of resource managers, community planners, and other stakeholders are increasingly asking for information regarding how climate change will affect South Carolina’s freshwater and coastal resources. They are interested in using this information for decisions related to infrastructure design, water system planning, vulnerability assessments, and ecosystem management. While climate change data, projections, and related information are also becoming increasingly available, many uncertainties around future climate change and its potential impacts often hinder its application. Furthermore, it is often not available in a format or at a scale that is easily translated to localand regional resource management decisions. This article highlights decision-maker questions about climate change in the Carolinas, approaches to using global climate change information, and opportunities to bridge the gap that often exists between scientific research and applications. We find that integration of future climate scenarios with water resources issues succeeds when robust links exist between climate variables and system response, and when scenarios from observed or simulated climate data are representative, plausible, and consistent. In general, there is no one “best” model that depicts future climate conditions, nor can climate science provide accurate predictions for specific locations and impacts. However, climate change projections can be used in conjunction with a variety of other tools and resources, such as vulnerability assessments and historical climate observations, to inform planning processes. Improved understanding of the system of concern, the linkages to climate, and the most important variables can help decision makers and researchers alike to develop the most relevant and informative analyses for climate-related questions. Ongoing engagement, as well as a willingness to experiment and share lessons learned, between and across the resource management and science communities will help to advance the climate change dialogue in the Carolinas and enhance the production and use of climate change information. INTRODUCTION Recent droughts, floods, and tropical storms in the Carolinas have exposed vulnerabilities of the region’s water resources to climate events. Climate also interacts with other stressors experienced in the southeastern United States such as rapid urbanization, land use change, and population growth (see for example, Nagy et al., 2011; Sanger et al., 2015; Terando et al., 2014). Water-related concerns frequently stem from the impacts these stressors have on current water availability and quality for both human and natural systems. Increasingly, a wide range of decision makers are also asking for tailored information regarding how climate change will affect South Carolina’s freshwater and coastal resources in the future. Temperatures are expected to increase across the Southeast, with the greatest warming projected to occur in the summer. Significant increases in the number of hot days (≥95° F) are also expected. However, there is less certainty about future precipitation patterns, including the frequency and intensity of rainfall events and tropical storms. Although many climate models do project increasing precipitation, higher temperatures and increasing water demands alone could adversely affect water availability (Ingram et al., 2013). Various organizations and agencies are beginning to consider future climate risks in resource assessments and planning. South Carolina examples include the Francis Marion National Forest Draft Revised Land Management Plan (USDA, 2015) and the State’s 2015 State Wildlife Action Plan (SC DNR, 2014). However, several challenges can hinder the incorporation of climate change information into many planning and management processes. For example, in the Southeast, one challenge involves the complexities and uncertainties related to the magnitude and direction of climate change. Although climate models can provide information relevant to the regional scale, there is uncertainty regarding how to translate this information to the local level, how to apply climate model output to specific decisions such as those related to water supply, and what are the most appropriate tools and resources for different contexts (Barsugli et al., 2012; Brown and Wilby, 2012; Kiparsky et al., 2012; Mote et al., 2016).