A holistic assessment of resilience to climate change hazards along the Mississippi and Alabama Gulf Coast, USA

Abstract

How communities prepare for, respond to, and recover from the impacts of climate-related natural hazards is conceptualized in terms of their resilience. Communities that can increase their resilience are in a better position to absorb the impacts and recover from damaging impacts when they occur. As a result, there is strong interest in the ability to measure resilience as a key step towards natural hazards and disaster risk reduction. Metrics aimed at measuring resilience suffer from a number of key limitations, however. For instance, hazard and community context are often ignored, attempts to validate resilience metrics are largely non-existent, and most indicator-based methods represent a broad-brushed approach that might neglect the true underlying drivers (or lack thereof) of resilience within communities. It is within this context that we propose to develop an integrated measurement framework to better understand drivers of resilience to climate-related hazard events. 

Our central hypothesis is that the robustness and utility of resilience metrics will be significantly improved by accounting for natural hazard context, community context, and scale of geography. 

Our holistic methodology includes: a) predictions of the magnitude of climate-related hazards on societal impacts using newly available resources; b) an accounting of asset exposure; c) the identification of context-specific characteristics that drive resilience from the “top-down” and “bottom-up”; and d) the assessment of resilience at multiple spatial scales. We intend the results of this research to lead to more reliable metrics of resilience for the assessment, communication, and enhancement of resilience along the Gulf Coast.

With improved metrics, our vision is to provide governments, risk managers, community and business leaders, and researchers new opportunities to create local initiatives and equitable public policy programs to increase the capacity of communities to mitigate, respond, and recover effectively and efficiently from damaging climate-related events when they occur.

Objectives

Following the axiom that “what gets measured gets managed,” the ability to measure resilience to climate-related hazards and disasters is increasingly being identified as a key step towards disaster risk reduction. Measuring resilience is difficult, however, and existing quantitative metrics of resilience suffer from key limitations. To account for limitations in the area of resilience measurement, the main objective of this study is to develop an integrated analytical framework that encompasses potential climate-related hazard impacts and community resilience in order to develop a new generation of resilience metrics that are hazard and community specific. We intend to:

1. Gain a better understanding of the characteristics that drive resilience along the Mississippi-Alabama coast using “top-down” and “bottom up” approaches;
2. Validate resilience metrics using long-term business and household recovery data from Hurricane Katrina that will span from 2005 to the present;
3. Develop theoretically based and methodologically sound resilience metrics that are context specific (e.g. hazard, livelihood, and community context);
4. Implement flood, hurricane storm surge, and drought impact models under different climate change scenarios using newly available data; and
5. Integrate community resilience assessments with the exposure of community assets and hazard impact scenarios for a holistic resilience assessment method. 

Methodology

Our methodology aims to integrate “quantitative” and “qualitative” approaches to delineate characteristics within communities that contribute to differential impacts and recovery potential from climate-related hazards. It is within this context that we intend to develop an integrated analytical framework that encompasses modeling potential climate-related hazard impacts coupled with methods to better understand and assess community resilience. We intend to apply this integrated methodology because in order to better understand resilience, it is imperative to recognize “who” and “what” is at risk first. Our methodology entails:

1. A flood impact assessment under various sea-level rise (SLR) scenarios where we will utilize flood depth grids published by the NOAA Office for Coastal Management in 2017 to visualize community-level impacts from coastal flooding; 
2. The modeling of potential hurricane storm surge inundation under the same SLR scenarios for the five Saffir-Simpson hurricane categories; 
3. Investigating the combined effects of droughts, SLR, and ground-water withdrawal on freshwater resources while working with stakeholders to develop sustainable management for allocating water uses among competing sectors;
4. The update and extension of an existing working waterfront inventory of businesses in order to describe the spatial distribution and potential financial losses to the region’s commercial building stock;
5.  Accounting for natural hazard context by developing a typology of drivers of resilience to floods, storm surge, and drought since variables that may be more appropriate for measuring resilience to one hazard may be less appropriate for measuring resilience to others; 
6. Validating resilience indicators at different scales, and for different recovery contexts, using the recovery from Hurricane Katrina (2005 – present) as a case study; and
7. Applying a resilience scorecard as a “bottom up” approach in two case study cities and along the region’s working waterfront to better understand drivers of resilience from a community context perspective.   

Rationale

Coastal communities are vulnerable to extreme hazard events such as storms, floods, and droughts that are expected to increase in frequency and intensity due to climate change.  How communities prepare for, respond to, and recover from the impacts of these events is often conceptualized in terms of their resilience. This is because communities that can increase their resilience are in a better position to absorb the impacts and recover from damaging events when they occur. There is strong interest in the ability to measure resilience as a result since the ability to measure the concept is being seen as a key step towards disaster risk reduction. Measuring resilience is difficult, however. Moreover, the leading approaches aimed at measuring resilience suffer from a number of key limitations. 

First, validation attempts are largely non-existent. Second, resilience indicators exhibit a large degree of uniformity in index construction approaches that ignore the context of the natural hazard or community context. The latter may result in misleading conclusions if dimensions of resilience pertinent to specific hazards or communities are ignored, or if weakly influential dimensions are overrepresented. Third, resilience metrics are uncertain due to data limitations. This is primarily because most indicator-based methods utilize a broad-brush approach using secondary source data such as those from the U.S. Census that may neglect the true underlying drivers (or lack thereof) of resilience within communities. Finally, few resilience assessments simultaneously capture the spatial distributions of a hazard’s impact potential, asset exposure, and the resilience of populations (and few do so at various scales of analysis).   

There is a critical need for methodological advancements that integrate the multiple stratums of relevant information outlined above to more holistically measure disaster resilience in order to improve the resilience of communities.