North Carolina Sea Level Rise Risk Management Study North Carolina Sea Level Rise Science Forum January 14, 2010 John Dorman, Geospatial and Technology Management Office

Impetus Behind Study North Carolina has been identified by NOAA as one of three states with significant vulnerability to sea level rise Largest estuarine system on U.S. Atlantic coast: Extensive barrier island chain, with several reaches vulnerable to over wash and breaching. 2,300 square miles of coastal land vulnerable to a 1.1 m SLR. The potential exposure demand an evaluation of the potential impacts to the ecology, environment, society, and economy of North Carolina The intent of this study / assessment is to: Define the risks associated with SLR and increased storminess; Support and facilitate the establishment and implementation of successful adaptation strategies

Origin of Study House Report 110-862, 2009 DHS Appropriations Bill IMPACTS OF CLIMATE ON FUTURE DISASTERS The Committee is concerned that FEMA does not have a robust climate change program in place to assess the potential impact of future disasters on its ability to prepare for, mitigate against, and respond to natural disasters; its managing of the National Flood Insurance Fund; and its efforts to help maintain accurate maps of the nation's flood plains. To begin to address the shortfall in information about the impact of climate change, the Committee provides $5,000,000 for the State of North Carolina to perform a risk assessment and mitigation strategy demonstration of the potential impacts of sea level rise in that state associated with long-term climate change. FEMA is directed to use the study results to assess the long-term fiscal implications of climate change as it affects the frequency and impacts of natural disasters, and to disseminate information from the study to other states to inform their climate change mitigation efforts.

High-level Questions for the Study What changes to coastal flooding hazards will possibly occur between 2009 and 2100 due to sea level rise and storminess? What built and living systems will be exposed to coastal flooding from sea level rise and increased storminess? What possible impacts / consequences (e.g. financial) will occur on the exposed built and living systems? What short-term and long-term strategies will result in efficient and effective prevention and/or alleviation of exposure and consequences from sea level rise and increased storminess? 4

Study Scope Develop reasonable scenarios of potential sea level rise, ‘storminess’, flooding, and development conditions for 4 “time slices” through 2100. Use these scenarios to perform system-wide risk assessments of (direct and indirect impact): Permanent flooding (sea level rise) Temporary flooding (tides, surge, wave heights) Annualized damages, 100 & 500-yr events, adjusted historical events Consider dynamic interactions (avoid bathtub approach) 5

Study Scope, cont. Identify efficient and effective risk management strategies including: Public policy Planning and zoning requirements Codes and standards Environmental Structural Analysis and monitoring Outreach Study will not include: Assessment of actions to reduce GHG emissions Impacts of inland rainfall flooding (limited to historical event simulations) Wind (as a separate hazard) Other natural hazards (e.g., drought, heat waves) Community-level action plans 6

Risk Assessment Approach Source-Pathway-Receptor (SPR) Framework Source: climate/weather events Pathway: routes taken to receptors Receptors: natural, built environments, society, industry

Conceptual Framework

Risk = HP x V x C (direct + indirect) Defining Risk Risk = HP x V x C (direct + indirect) Resilience HP = Hazard Probability V = Vulnerabilities C = Consequences

Risk Assessment – Types of Losses with SLR 10

Economic Modeling Approach

New Data / Methodologies / Models SoVi / Uvi into Risk Assessment 12

Answers / data / models / products will be: Repeatable Defensible Quantitative Transferable and Non-proprietary Scalable Spatial Risk Assessment Completed by December 2010 Risk Management Strategy Analysis by July 2011

Study Audience Secondary Study Audience Primary Study Audience – The primary audience for this study are federal and state government policy makers U.S. Congress North Carolina General Assembly Governor FEMA \NFIP Other Coastal States Secondary Study Audience Coastal Counties / Municipalities NC State Departments with Regulatory Authority US Department of Defense - Military Bases in North Carolina coastal areas DHS – NIPP Federal Agencies with Regulatory Authority (i.e., NOAA, EPA, USACE)

Study Strategy Will leverage relevant existing, in-process, and planned information sources to maximum degree practicable: Datasets e.g., topography, critical infrastructure, shoreline Models e.g., hazard Identification, risk assessment Research/Studies e.g, sea level rise studies, socioeconomic forecasts Coordinate with, and build upon other studies Scenario-based approach to address an uncertain future Seek broad input throughout phased-study process Collaborative effort of state and federal agencies, UNC system, private sector, other stakeholders Build consensus and acceptance through Advisory Committee

Scenario-Based Approach Scenarios of combined potential sea level rise, storminess, resultant flooding, development and socioeconomic conditions for 4 “time slices” through 2100: 2025, 2050, 2075, 2100 Each scenario representing an equally plausible future condition, and having equal likelihood of occurrence In sum, representing the full range future conditions Starting point for examining questions about an uncertain future Not specific predictions or forecasts

Conceptual Scenario Approach Overlapping scenarios allows efficiency in modeling and assessment efforts.

Data/Study Leveraging The Study will leverage relevant existing, in-process, and planned information sources to maximum degree practicable: Datasets e.g., topography, critical infrastructure, shoreline Methodologies / Models e.g., hazard Identification, risk assessment Research/Studies e.g, sea level rise studies, socioeconomic forecasts Acquire new data as deemed necessary and that will be available within time and budget Develop new methodologies to fill existing inadequacies. 18

North Carolina Floodplain Mapping Program DFIRM Data Digital GIS-data collected by the NCFMP to support the production of DFIRMs. All data are, or will shortly be, statewide. Data are available for download by county. Imagery DFIRM Mapping Data Engineering & Inventory Data 19

Topography State-wide LiDAR 2001, 2003, 2005 ≤ 20 cm vert. RMSE 3 m nom. point spacing Seamless 10-m DEM assembled for surge study 20

Storm Surge Model North Carolina Floodplain Mapping Program Storm Surge Study Conducting update of coastal flood frequency elevations for entire state Coupled 2-D water circulation (ADCIRC) and wave model (SWAN & WW3) ~100 m horizontal resolution along coast JPM frequency analysis of extra-tropical and tropical event driven storm surge Baseline return period analysis will consider 675 tropical events Utilizing RENCI HPC resources Model framework will be leveraged to highest extent possible 21

Integrated Hazard Risk Management Collect and merge locations and parcel data for all buildings > 1,000 ft2 (footprint area) ~7.5 million Documented locations and interdependencies between all Critical Infrastructure / Key Resources (18 DHS Sectors) Capturing First / Finished Floor Elevations for all coastal counties Collected socioeconomic data (SoVi and UVi)

Integrated Hazard Risk Management Model Critical Infrastructure Failure Interdependencies Damage / Consequence Methodology by Hazard Develop of Enhanced Risk Communication Tools

Advisory Committee Comprised of members from: State agencies Federal agencies Universities Stakeholder organizations Other public and private sector experts Purpose is to ensure a broad range of viewpoints are considered and to build consensus on the final study results Advisory Committee Role: Assist with identification of existing and in process datasets and studies of relevance Provide input on proposed analytical approaches and policy strategies Review and provide feedback on draft and final analytical study results and reports See Table 8 in study plan for members

Sea Level Rise Risk Management Study Process and Timeline Dec 2010 July 2011 Current Status 25

Current Activities Final review by Advisory Committee on the detail study questions that support the four High-Level Study questions. Completing review of past and present studies to document methodologies and modeling Assessment of the existing institutional capabilities of the state to address / confront sea level rise in North Carolina Select data acquisition – (e.g. finished floor elevations) Review of proposed methodologies associated with: Coastal Geomorphology Evolution Analysis Modifying / Utilizing ADCIRC/JPM to Support NC Sea Level Rise Risk Study Modeling Land Use / Development Scenarios

Thank You