Recurrent hotspot zones of projected heat and dry-spell persistence across MENA

This study identifies recurrent hotspot zones of projected heat and dry-spell persistence across the Middle East and North Africa (MENA). Using an ERA5-anchored Stacking-EML product integrating six CMIP6 simulations under SSP1-2.6, SSP2-4.5 and SSP5-8.5, we quantify changes in the Warm Spell Duration Index (WSDI) and Consecutive Dry Days (CDD) across three future horizons. Spatial autocorrelation and local clustering reveal strong spatial dependence and recurrent neighbourhood-scale clustering. Hotspot recurrence is treated as a scenario–horizon diagnostic of the integrated Stacking-EML product, distinguishing repeatedly detected zones from scenario- or period-specific patterns without implying robustness across independent CMIP6 models or internal variability.

WSDI and CDD exhibit contrasting spatial architectures, while their spatial intersection defines a more selective WSDI–CDD recurrent-hotspot overlap. This overlap does not demonstrate temporal co-occurrence, joint dependence or physical coupling between the two persistence indices. Recurrent hotspot zones are thresholded spatial masks derived from local Getis–Ord classifications across the analysed scenario–horizon combinations and should not be interpreted as directly observed physical pathways or dynamically continuous corridors. Population-count and cropland-area overlays indicate substantial human and agricultural exposure within recurrent hotspot zones, whereas the WSDI–CDD overlap identifies a smaller exposure footprint. These overlays represent spatial exposure rather than vulnerability, realised impacts or overall climate risk. Together, the framework extends persistence-extreme assessment beyond descriptive Δ-change mapping by providing recurrent hotspot diagnostics for regional hazard–exposure screening.