Heat, employment and deprivation: compound climate burden in an island tourism economy

Compound climate vulnerability—the geographic co-location of climate exposure, concentrated employment and residential socio-economic disadvantage—remains methodologically underdeveloped at the sub-municipal scales required for operational adaptation planning. Tourism-dependent island economies are a demanding test case for it, because their employment is organised into sharply bounded enclaves and their climatic gradients are steep over very short distances. This study develops and applies a triple-burden spatial clustering framework across the Canary Islands archipelago (a Spanish European Outermost Region), using the 1387 of its 1396 census tracts for which all three dimensions are available, integrating residential vulnerability indicators (INE Atlas de Renta), sectoral activity data (SABI business registry) and dynamically downscaled CMIP6 climate projections (WRF V3.9.1.1 at 3 km horizontal resolution) under SSP1-2.6 and SSP5-8.5 scenarios for mid-century (2030–2059) and end-century (2070–2099) horizons. Non-parametric distributional comparisons reveal trivial effect sizes for all four heat indicators under every future scenario at the archipelago level (|Cliff’s δ |< 0.15), the only two exceptions being small and historical ( δ = −0.19 and −0.22), demonstrating that sectoral attribution alone does not capture climate vulnerability differentials in this insular subtropical setting. Territorially, however, the burden is sharply concentrated. The intersection of high employment concentration with high residential poverty identifies 181 census tracts, 13.1% of the territory, containing 85.1% of tourism-dominant employment; this bivariate core is the stable finding, invariant to how thermal burden is operationalised. Adding a third criterion—the projected increase in tropical nights—isolates 68 tracts (4.9% of the territory) capturing 37.1% of tourism-dominant employment, 2.6 times chance expectation against a null conditioned on employment size, and 7.6 times against an unconditional null (10,000 permutations, p < 0.001). The resulting set is predominantly metropolitan rather than touristic—47 of its 68 tracts lie in island capitals and other urban municipalities, 18 in Las Palmas de Gran Canaria alone—so compound burden here is a property of dense, deprived urban employment centres as much as of resort enclaves. Because six defensible thermal specifications yield clusters agreeing only weakly with one another, the trivariate set is reported as a prioritisation within that core under one explicit threshold-based criterion rather than as a uniquely determined solution. Under SSP5-8.5 end-century, projected worker-day heatwave exposure rises 6.4× over historical baseline. Because 63–70% of heatwave days fall within the June–September window that coincides with peak hospitality staffing, the seasonal burden during the tourism high season is amplified by a factor of 1.9–2.1 relative to a uniform annual distribution, and mean summer heatwave days rise approximately eightfold under the same scenario. Two conclusions follow. Compound climate burden in this archipelago is organised by where employment concentrates and where deprivation is, not by which sector employs: the tourism workforce is a component of the burdened geography rather than its defining feature. And the framing consequence is that adaptation policy in outermost island regions needs territorial instruments delivered by municipalities alongside the sectoral instruments that the tourism-focused literature has emphasised. The methodological framework is transferable to other insular and outermost territorial contexts. Results derive from a single dynamical downscaling chain and from stationary 2022 employment patterns, and quantify exposure rather than physiological or economic impact.