Spatiotemporal Coupling of Extreme Heat Dynamics and Socio-economic Fragility: A District-Level Risk Assessment in Türkiye (1980–2024)

As the Mediterranean Basin warms at a rate 20% faster than the global average, Türkiye faces an escalating threat from compound extreme heat events. However, conventional risk assessments frequently rely solely on meteorological data and fail to consider the nuanced socio-economic disparities that influence a community's adaptive capacity. This study presents the first high-resolution (district-level, N=973) spatiotemporal risk assessment of heatwaves in Türkiye over a 44-year period (1980–2024). Utilizing ERA5-Land reanalysis data, we constructed a comprehensive Physical Heat Hazard Index (PHHI) comprising seven metrics, including novel indicators such as Tropical Nights (TR25) and Heating Velocity (Sen's Slope). Concurrently, a dynamic Socio-economic Vulnerability Index (SVI) was developed using a weighted household socio-economic status (SES) model that assigns progressive weights to lower-income groups to capture the fragility of populations with the lowest adaptive capacity. Using a rank-based method and bivariate choropleth mapping, we found important "risk hotspots" where physical exposure and social vulnerability interact. Our results reveal a stark climate injustice divide: while the wealthy coastal districts of the Aegean and Mediterranean exhibit high thermal stress offset by high adaptive capacity, the Southeastern Anatolia Region and the Adana Plain are trapped in a "high hazard–high vulnerability" cluster, representing a climate trap. These findings call for a paradigm shift from uniform meteorological warning systems to territorially explicit, socioeconomic resilience strategies that prioritize deep-risk zones through targeted interventions such as public cooling centers and occupational heat protections.