A. The intensification of the Urban Heat Island (UHI) effect, a phenomenon where metropolitan areas are significantly warmer than their surrounding rural counterparts, presents a critical challenge for urban planners and environmental scientists. This thermal disparity, primarily caused by the replacement of natural landscapes with heat-absorbing surfaces like asphalt and concrete, exacerbates energy consumption for cooling, contributes to air pollution, and poses health risks during heatwaves. In response, a suite of mitigation strategies has been proposed, with vegetated or 'green' roofs emerging as a particularly popular solution. While their capacity to cool the buildings they sit upon is well-documented, a more advanced and pressing question concerns their collective influence on the wider urban microclimate, specifically their role in cooling entire dense city districts. B. The primary mechanisms through which green roofs combat elevated temperatures are twofold: shading and evapotranspiration. The vegetation and its underlying substrate, or growing medium, provide a thermal-insulating layer that shields the roof membrane from direct solar radiation. This alone significantly…
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