Considering socio-political framings when analyzing coastal climate change effects can prevent maldevelopment on small islands

Adapting to climate change and sea level rise is challenging on small islands. False adaptation can lead to adverse impacts on natural and societal dynamics. Therefore, an interdisciplinary perspective on the interaction of natural dynamics, societal demands, and political decisions is crucial. In this sense, this study scrutinizes coastal processes and socio-political dimensions of erosion on the reef island Fuvahmulah, the Maldives. The national government and Fuvahmulah’s population have an opposed perception and attribution of the drivers and processes behind Fuvahmulah’s most pressing coastal issue – coastal erosion. To review these perceptions, natural dynamics are recreated with process-based methods and discussed regarding present and projected marine pressures. Population surveys and interviews with actors in coastal development complement the physical insights into erosion on Fuvahmulah and describe the socio-political dimension of climate change adaptation on small islands. This interdisciplinary approach demonstrates how small-islands’ adaptive capacities are typically impaired and disclose the potential of local knowledge to overcome maldevelopment.


Photoscan Settings
Photoscan is performing a three-dimensional, virtual reconstruction of the coastal areas of Fuvahmulah, based on the aerial images, recorded in three field campaigns. Tab. 1 shows the settings within the software for each reconstruction. The settings resulted in digital elevation models (DEMs) with a similar resolution of ≈ 3.5 cm px −1 .

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Supplementary Information for the article: Considering socio-political framings when analyzing coastal climate change effects can prevent maldevelopment on small islands (David et al., 2021) 2 Wave Statistics   Tables 2 and 3 display the associated median and IQR values for the boxplots of the significant wave height H s around Fuvahmulah, as seen in Fig. 5 of the main manuscript. The data in Table 2 is based on the Collaboration for Australian Weather and Climate Research (CAWCR) wave hindcast collection 1 for the time period 1979 -2019. Table 3

Current Velocities
Since the study focuses on the wave driven longshore currents, ocean circulation around Fuvahmulah and the tidal current velocity was disregarded for sediment transport processes. To justify this simplification, the following section compares velocities from ocean circulation, tidal current velocities and wave-induced currents with each other. The velocity of the ocean circulation was derived from monthly means of the European Centre for Medium-Range Weather Forecasts (ECMWF) Ocean ReAnalysis System 5 (ORAS5) reanalysis data-set 3  Example: "Due to high currents and huge waves -the soil from coastal areas are wiped out." (S1 063) -Less trees (15 %) Statement states that less trees are found on the island as an environmental change.
Example "It's getting hotter." (S1 084) • No (7 %) Question 3: Do you feel safe to live in Fuvahmulah with regard to sea-level rise? (Open-ended question, categorized, Respondents=116) Codes (Coding rule, Example statement): • Feels safe (52 %) Statement demonstrating that the respondent feels safe on the island without doubt. Example: "Currently the safest island in Maldives is Fuvahmulah because it has highest coast." (S1 026) • Does not feel safe (25 %) Statement demonstrating that the respondent does not feel safe on the island. Example: "No, it's not safe. I would prefer to move to some other island." (S1 076) • Inconclusive (22 %) Statement does not allow a clear valuation.
Supplementary Information for the article: Considering socio-political framings when analyzing coastal climate change effects can prevent maldevelopment on small islands (David et al., 2021) Example: "If we get flood than we won't survive. This island's coasts are higher but middle of island is lower. It's like a bowl." (S1 073) • Don't know (1 %) Question 4: What are elements of the natural environment of Fuvahmulah that are important to you?
(Open-ended question, categorized, multiple responses possible per person; Respondents=116; Re-sponses=235) Codes (Coding rule, Example statement): • Trees (17 %) Statement mentions trees as an important element of the natural environment. Example: " "Trees around the island." (S1 114) • Beaches (8 %) Statement mentions the beach as an important element of the natural environment. Example: " "Nice beach." (S1 049) • Lakes (8 %) Statement mentions lakes as an important element of the natural environment. Example: " "North lake near the house. It's very peaceful and in the evening, we go there with our children." (S1 012) Question 5: How is the community involved in the decision-making process regarding the development of the island? (Open-ended question, categorized, Respondents=115) Codes (Coding rule, Example statement): • Regular involvement (17 %) Statement arguing that community is included in the decision-making process. Example: "Are included. Good things and bad things come out of it." (S1 031) • Sporadic involvement (17 %) Statement arguing that the community is included in the decision-making process from time to time or in limited ways. Example: "Sometimes they take our opinions, and sometimes they just go ahead with it." (S1 033) • Insufficient involvement (49 %) Statement clearly demonstrating dissatisfaction with how the community is involved in the decision-making process. Example: "Not involved. The leaders of the community decide it for themselves." (S1 107) • Inconclusive (7 %) Statement does not allow a clear valuation.
Example: "Don't know about other, but if I am asked for involvement, I go to help them." (S1 109) • Don't know (8 %)

Data availability
The field data 6 from the aerial surveys and bathymetry for numerical modeling is publicly available through doi.org/10.5281/zenodo.4304049. Wave climate data is publicly available from the respective services and homepages of CAWCR (CSIRO Data Acess Portal), ECMWF (Copernicus Climate Data Store) and National Oceanic and Atmospheric Administration (NOAA) (WAVEWATCH III®Hindcast and Reanalysis Archives). For further information of the climate data, see also Table  1 in the main article. Source data supporting the social sciences' finding are provided within the supplementary materials of this paper.
Other raw data (for example interview transcripts) on the social sciences part that support the findings of this study are protected and not publicly available as they contain personal information that could compromise research participant privacy. Other data from the social science part can be made available from the social science team (B.M.W.R. and A.H.) upon reasonable request.

Code availability
The aerial images were processed with the Structure-from-