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

Small, low-lying reef islands face rising risks from sea-level rise, storm surges, and swell waves. Healthy reefs can dissipate wave energy and supply sediments, but anthropogenic pressures and climate change threaten these services. In the Maldives, centralized, hard-engineered coastal protection has often disrupted natural morphodynamics and ecosystem functions. This paper investigates coastal erosion on Fuvahmulah, Maldives, where national government narratives attribute erosion to climate change and sea-level rise, while the local community often attributes it to harbor construction. The study asks what the root drivers of erosion are and how socio-political framings influence adaptation choices. Using the DPSIR framework, the study links oceanic-climatic and socio-political pressures to state changes and impacts, introduces the concept of maldevelopment (socio-political drivers that foster repeated maladaptive actions), and demonstrates how local knowledge can inform low-regret, context-appropriate adaptation strategies.

A qualitative content analysis synthesized peer-reviewed literature, legislation and regulations, environmental impact assessments (EIAs/ESIAs), and gray literature on climate change adaptation and coastal protection in the Maldives. Sources included ministry documents, UNDP reports, and site-specific assessments for Fuvahmulah’s seaport and coastal projects (e.g., MEE/UNDP 2011; EIA/ESIA 2016; technical design reports; NCEA reviews). The review examined: (1) governance responsibilities for coastal protection, (2) historical reliance on hard infrastructure, (3) the framing of coastal protection within national climate change narratives, and (4) compliance and quality issues with EIAs. Prior work documents widespread hardening of coasts, limited participatory decision-making, top-down project implementation, and frequent disregard of reef-based sediment dynamics in design—trends consistent across Maldives and other SIDS.

The study employed an interdisciplinary mixed-methods design combining geospatial measurements, numerical modeling, wave climate analyses, and social research.

• Digital Elevation Models (DEMs): UAV photogrammetry surveys captured coastal topography in March and September 2017 (DJI Phantom 4) and March 2019 (DJI Phantom 4 Pro). Images were processed in Agisoft Photoscan Pro (SfM-MVS) into DEMs at ~3.5–5 cm/px. 2019 DEMs were georeferenced with GCPs; 2017 DEMs used GNSS initial positioning and virtual GCPs tied to 2019. Cross-sections quantified shoreline and profile changes along Fuvahmulah’s east coast.
• Wave climate data and validation: Time series from CAWCR (WAVEWATCH III), ECMWF ERA5 (WAM/IFS), and NCEP-EMC (WAVEWATCH III) were extracted from closest grid nodes (spatial resolution 0.4–0.5°, hourly or 3-hourly). Wave heights were validated against harmonized Satellite Radar Altimetry (GFZ ADS) in the vicinity of Fuvahmulah (1993–2018) using cross-correlation and RMSE metrics. Future projections used CAWCR RCP4.5 and RCP8.5 (coarser 1.0°, 6-hourly) to compare significant wave heights between 1986–2005 and 2081–2100.
• Numerical modeling: Two models reconstructed hydrodynamics and inferred sediment transport processes. • Delft3D (D3D) WAVE/FLOW phase-averaged modeling with sediment transport formulations. Idealized bathymetry (offshore depth 100 m; fringing reef 4–17.5 m; island at +3 m MSL), rectilinear grid refined around the island (Δx=67 m, Δy=15 m), 1 m erodible sediment layer (ρsed=2.0 g/cm³; D=200 µm; fMOR=2). Forcing used a PM spectrum with Hs=2.3 m (99th percentile), Tp=17 s, peak directions θ=202.5° (SSW) and θ=135° (SE). • BOSZ depth-integrated (2DH) Boussinesq-type model to resolve wave transformation and wave-induced currents over the measured reef bathymetry. Grid 7.5 m, offshore truncated at 60 m depth, TMA spectra with Hs=2.3 m, Tp=17 s, θ=202.5° and 135°. Simulations compared cases with and without port structures to identify current deflection and sediment pathway blockage. Tides and background ocean circulation were neglected to isolate wave-driven longshore processes.
• Social research: Two door-to-door household surveys across all eight wards (randomized household sampling; approx. every eighth household). Survey 1 (Mar–Apr 2017): n=116 (ages 14–86) on environment/coast understanding, climate change perceptions, community life, and coastal protection attitudes. Survey 2 (Jan–Feb 2019): n=98 (ages 14–84) on community life, engagement potential, and governance framing. Mixed closed and open questions; qualitative coding and content analysis with MAXQDA. Semi-structured interviews (n=32) with national-level actors (ministries, NGOs/IGOs, researchers) and local-level actors (council members, NGOs) explored decision-making, participation, and policy framing. Ethical procedures included informed consent and anonymization (except ministry officials).

• Measured erosion: DEM cross-sections (2017 vs. 2019) show severe, spatially varying erosion along the east coast. The southeastern coast adjacent to the seaport exhibits continuous structural erosion averaging ~0.3 m over two years with maxima of ~1.33 m; uprooted trees and exposed bedrock corroborate field observations. Erosion rates decline northward; the dynamic Thoondu spit in the northeast showed slight accretion consistent with seasonal behavior. Central east-side retreat was occasional and not continuous (0.26–0.28 m at some transects).
• Wave climate: Around Fuvahmulah, SSW waves dominate in the dry season (Nov–Feb), and SE–SSW in the wet season (Apr–Sep). Median monthly Hs ~0.98 m (March) to ~1.71 m (July); historical maximum Hmax 3.32 m (June 22, 1987). Cross-dataset agreement is high (annual mean R≥0.89 among CAWCR/ERA5/NCEP), and SRA validation shows ERA5 best matches SRA (RMSE ≈ 0.295 m). CMIP5-based CAWCR projections show no significant change in Hs distributions by late 21st century under RCP4.5/8.5 for the region.
• Modeled sediment dynamics: D3D indicates the southern and southeastern reef supply sediments to the east coast, with seasonal redistribution. BOSZ reveals two key mechanisms by which the port induces erosion: (1) the breakwater obstructs sediment delivery to the east coast by blocking and deflecting wave-driven currents (θ=202.5°), pushing suspended sediments off the reef into deeper water; (2) for θ=135°, longshore transport capacity persists but, with sediment supply curtailed, the current entrains beach/nearshore sediments, driving erosion along the east coast. The port is located at a hotspot critical for island-wide sediment routing.
• Governance and perceptions: Surveys identify erosion as the top issue (closed question: 27% of 345 mentions). In an open question about observed environmental changes, ~36% mentioned erosion; of these, 20% explicitly linked it to the harbor construction. Regarding sea-level rise, 52% reported feeling safe on Fuvahmulah, citing protection by coastal ridges and the reef. Participation is perceived as lacking: 49% report insufficient cooperation with politicians; 83% want more involvement in development decisions. Interviews and document analysis show centralized, top-down decision-making, heavy reliance on external funding/consultants, and frequent preference for hard-engineered solutions; EIAs/ESIAs often dismiss soft/ecosystem-based options based on questionable assumptions (e.g., no sediment source), despite evidence of reef-derived sediments.
• Maldevelopment: The study introduces and evidences “maldevelopment” as the socio-political driver behind recurrent maladaptation—systematically favoring hard infrastructure that disrupts reef dynamics, diminishes natural adaptive capacity, and locks in future armoring. For Fuvahmulah, plans to revet the majority of the east coast represent such a pathway and risk approaching anthropogenic tipping points.
• Low-regret option: Sediment bypassing around the port is identified as a feasible, low-regret measure to restore alongshore sediment supply and nourish beaches, in contrast to extensive revetments that further degrade reef-island dynamics.

Findings reconcile divergent perceptions of erosion drivers by combining field evidence, wave climate analysis, and process-based modeling with social inquiry. The results demonstrate that the seaport, not contemporary changes in wave climate, is the primary proximate driver of the severe east-coast erosion by interrupting the natural sediment transport. This mechanistic understanding validates local knowledge and challenges national narratives that frame erosion chiefly as a climate change impact. The concept of maldevelopment captures how centralized, hard-engineering preferences, limited local participation, and externalized expertise can institutionalize maladaptive choices, leading to cascading environmental and societal impacts and narrowing future adaptation options. The study argues for adaptation pathway planning that emphasizes working with natural reef dynamics, incorporates local knowledge, and prioritizes flexible, low-regret interventions (e.g., sediment bypassing, nourishment) with ongoing monitoring and iterative adjustments. Insights are scalable to other Maldives islands and SIDS where similar socio-political structures and reef environments exist.

This study advances an interdisciplinary approach to coastal adaptation on small reef islands by: (1) defining and evidencing maldevelopment as a socio-political driver of repeated maladaptation, (2) quantitatively documenting erosion adjacent to Fuvahmulah’s port and mechanistically linking it to disrupted reef sediment pathways, and (3) demonstrating the value of local knowledge for identifying effective, low-regret measures. It recommends shifting from generic, hard-engineered coastal defenses toward context-specific, nature-compatible strategies such as sediment bypassing and nourishment, embedded in adaptive pathway planning with genuine local participation and continuous monitoring. Future research should refine sediment budget quantification around reef island hotspots, evaluate operational designs for sediment bypassing under varying wave climates and sea-level rise scenarios, and develop governance frameworks that integrate local stakeholders throughout project lifecycles to prevent maldevelopment.

• Numerical modeling: D3D used idealized bathymetry and coarse grids; port structures were excluded to represent pre-disturbance pathways; BOSZ resolved currents but did not compute sediment volumes. Only two peak wave directions and storm-level Hs=2.3 m were modeled; moderate conditions and tidal/ocean currents (omitted) also influence transport. Thus, results are process-indicative rather than volumetrically quantitative.
• DEM-based erosion detection: Early-stage undercutting at the beach toe may be underrepresented until failures occur; airport-adjacent beaches were a no-fly zone.
• Climate variability: The study did not perform an in-depth assessment of recent climate variability effects on morphology beyond long-term wave climate statistics.
• Social data: Although randomized household sampling was used, surveys and interviews reflect specific time frames and may be subject to response biases; some interviews were not recorded (notes/memos used). Generalizability beyond similar SIDS contexts should consider governance and environmental differences.
• EIA document analysis: Depended on available English-language documents and selected gray literature; some local (Dhivehi) materials were not analyzed.