Changing Coastalscapes: Advancing methods to support local climate adaptation

As climate change accelerates, socio-ecological systems are transforming in unprecedented ways. Species and habitats are shifting, climate-induced extreme weather is intensifying, and human understandings of climate change and the places it manifests in are changing. In response, governments must embrace new methodological approaches that enable appropriate responses to community connections with and interpretations of places at risk. Local governments, where climate change impacts are place-specific and contextual, must act with this in mind. However, existing methods rarely capture the conflicting spatial and conceptual discourses around climate change that emerge in these local places, ultimately influencing community acceptance of climate adaptation actions. The socio-ecological nature of climate change means transdisciplinary and mixed methods that cross the qualitative-quantitative divide are central to informing adaptation policy.

These issues are particularly poignant within coastal regions where the underlying processes that shape place (e.g., coastal erosion, beach formation, vegetation zones) also shape communities as they draw people in to live, work, and recreate in unique ways. Thus, coastal socio-ecological systems – termed here coastalscapes – provide a multi-dimensional context for evaluating the efficacy of methods that identify spatial patterns of values, climate change impacts, and their relation to community discourses. In this thesis, I use a coastalscape case study in Southern Tasmania to address my primary aim of contributing fit for purpose methodological advances that support local responses to climate change. To achieve this aim, I address three research questions: (1) Which methods effectively enable an understanding of spatial patterns of community values and perceived risks; (2) Which methods can identify climate and landscape discourses; and (3) How can novel combinations of methods address critical knowledge gaps for better place-based climate adaptation responses? This methods-driven thesis makes an original contribution to transdisciplinary methodologies by innovating on Public Participation GIS (an inclusive practice of collecting, analysing, and visualising geospatial data elicited from local people) analysis techniques, testing novel Q-method (a quantitative technique for eliciting, evaluating, and comparing individual perspectives on controversial issues) approaches, and demonstrating how Q+PPGIS effectively reveals spatial and conceptual discourses in a coastalscape experiencing the increasing effects of climate change.

In developing new approaches, I identify two common and key methods: Public Participation GIS (PPGIS) and Q-methodology (Q). I conduct a systematic literature review to explore the individual use of PPGIS and Q as well as their robust coupling, which is described and defined as Q+PPGIS. I find that while both PPGIS and Q are common in the environment and climate change planning literature (e.g., landscape valuation, psychometric visual preferences, spatial coastal planning, conflicting land-use beliefs), their integration and application to assist adaptation decision-making is rare. Further, the coupling of both PPGIS and Q within a single study is extremely limited (n = 30 identified studies). Given this gap in the literature, my systematic quantitative literature review defines the critical steps in conducting Q+PPGIS studies and identifies the relevance of this method for examining contentious topics like climate change or land-use planning.

Responding to the results of my literature review, I then apply PPGIS, Q, and Q+PPGIS methods to my case study. Focusing on climate adaptation planning in the Huon Valley coastalscape, I provide novel extensions for each method to ensure they are fit for purpose and accessible for local governments. These methods are typically conducted in person (e.g., participatory mapping on paper), but due to COVID-19, survey methods have rapidly moved online. Much of my own study was inevitably conducted through electronic survey methods, and in doing so, I advance a new approach for ensuring survey respondent recruitment and screening is robust, as well as identifying important steps for post-data processing to identify potentially fraudulent responses and certify data reliability.

My PPGIS analysis draws upon landscape value and climate change risk mapping with local residents and finds strong spatial and non-spatial correlations between mapped landscape values and spatial perceptions of climate risk, both collective and individual pairings. While analyses of social-psychological correlates (i.e., risk perception scale) were inconclusive (R2 < 0.5), there were significant correlations of mapped values and risks with physical assets in the region.

Q-method analyses of participants suggest that there are five climate risk discourses (e.g., “Governments must mitigate”) accounting for 73% of the variance and four landscape value factors (e.g., “Pristine wilderness”) accounting for 65% of the variance. Climate risk discourses differentiate by responses around the scale of responsibility, the priority of adaptation vs. mitigation, and the community’s resilience. In contrast, landscape value discourses differentiate by preferences for wilderness, prioritisation of accessibility, and the consequence of industry presence.

To demonstrate the integration of results via Q+PPGIS, I use the Q-derived landscape value factors accounting for the majority of the variance to delineate three spatial regions in Huon Valley. I then compare these regions with landscape value and climate risk PPGIS data. Results indicate that mapped value and risk hotspots cluster in the highly modified, accessible, and impacted eastern portion of the region, while lower values and risks cluster in the protected wilderness areas to the west. The liminal region predominately under forestry management demonstrates unique value and risk clustering, which “Pristine wilderness” respondents perceive as demonstrating wilderness characteristics. Compared with general PPGIS results, the Q+PPGIS approach identifies and visualises land-use planning challenges, limitations with established PPGIS analyses, and framing opportunities for local planners.

Findings from my thesis present novel applications of traditional methods (PPGIS and Q) to make them fit for purpose in local climate adaptation planning contexts and provide the methodological guidance needed to adopt new methods (Q+PPGIS and identifying fraudulent responses in online surveys) that can support local climate change adaptation planning. The Q+PPGIS methods demonstrated here operationalise community-based mapping and risk-value discourses as decision-making tools. In applying these methods to the local coastalscape case study, my thesis develops new knowledge and makes an original contribution to local adaptation planning capacity by mapping relationships between landscape values, spatial perceptions of risk, and their conceptual correlates, thus underscoring the need for new frames or narratives for conveying the climate change story.