Ornelas, A.J.A., Cordeiro, A.M.R. and Lameiras, J.M. (2026) ‘Green spaces: Urban heat island mitigation and building climate resilience in Coimbra’, Atmosphere, 17(3), 284. https://doi.org/10.3390/atmos17030284.

Ornelas and colleagues make temporal sampling indispensable to spatial diagnosis. Their multi-site observations of near-surface air temperature in Coimbra distinguish recurrent intra-urban thermal hotspots from cooler green and blue settings, tracking contrasts across different parts of the day and different urban conditions. Santana and the Seminary surroundings emerge as prominent heat-exposed locations; the Botanical Garden and Mermaid Garden operate as local cooling refuges. The research instrument is not a single climatic map but a sequence of situated measurements, interpreted against urbanisation intensity, surface cover and site context. This matters because an apparently homogeneous neighbourhood may change thermal character within hours. It would be incorrect to infer individual thermal comfort, health outcomes or the causal effectiveness of a proposed design intervention directly from those temperature contrasts. The paper nevertheless establishes a powerful empirical requirement: exposure must be observed at the scale and frequency at which urban conditions actually diverge. The city has no single temperature, and an observation made once should not silently become a permanent attribute of place.