Determining the contiguous effect of local climate zones (LCZs) on the land surface temperature distribution in eThekwini municipality

Temperature extremes threaten thermal comfort and public health, making it essential to understand the spatial factors influencing urban heat. This study investigated land surface temperature (LST) variation across boundaries of Local Climate Zones (LCZs) in eThekwini Municipality, South Africa. Landsat-derived LST and LCZ maps were used to quantify edge effects by extracting LST values at 25 ​m intervals up to 500 ​m from shared LCZ boundaries. Results demonstrated that edges of built-up LCZs were strongly influenced by the adjacent LCZ type. Dense vegetation and water LCZs cooled adjacent built-up edges by up to 4 ​°C, while transitions into other built-up LCZs exhibited gradual warming of 1–2 ​°C. Statistical analysis confirmed strong edge–distance associations (R 2 ​> ​0.7, p ​< ​0.05), with cooling effects extending up to 300 ​m into built areas. Conversely, built-up LCZs elevated temperatures along the edges of vegetation and water classes. These findings highlight that edge-related thermal gradients are transitional, not abrupt, and are driven by surface properties such as evapotranspiration, albedo, and heat storage. The study concludes that strategically inserting vegetation-based LCZs at ∼300 ​m intervals within built-up zones can maximize cooling benefits and mitigate urban heat risks. Beyond broad LCZ temperature contrasts, urban climate policy must account for edge effects when planning climate-resilient cities. • Edge temperature depend on type of neighboring LCZ. • Edges of built-up were cooler next to vegetation and water than other LCZs. • Edge temperature differed significantly with that at LCZ core. • Vegetation about every 300m in built-up areas has a strong cooling effect. • Temperatures vary between and within LCZs as well as with distance from the edge into and out of LCZs.