NICL AO English Mock Paper 2026: FREE Practice PDF & Live Quiz

Cities often record higher temperatures than nearby rural areas, a phenomenon known as the urban heat-island effect. Concrete, asphalt and dark roofs absorb solar energy during the day and release it slowly after sunset. At the same time, dense construction can restrict air movement, while limited vegetation reduces the cooling produced by shade and evapotranspiration. The result is not merely uncomfortable weather. Prolonged heat raises electricity demand, worsens air pollution and increases health risks, especially for older people, outdoor workers and families without reliable access to cooling. Urban planners are testing several ways to mitigate this effect. Planting street trees can lower surface temperatures and make walking routes safer. Green roofs add vegetation to buildings, while reflective roofs send a larger share of sunlight back into the atmosphere instead of storing it as heat. Permeable pavements can also help by allowing rainwater to enter the ground, where gradual evaporation provides additional cooling. No single measure, however, works equally well everywhere. Trees need water and maintenance, and their roots may damage poorly planned pavements. Highly reflective materials can create glare if selected without considering surrounding buildings. In colder regions, they may also reduce a small amount of useful winter heat gain. For this reason, specialists recommend neighbourhood-level planning rather than applying one solution across an entire city. Equity is another concern. Low-income neighbourhoods often have fewer trees, more exposed surfaces and less access to air-conditioned public spaces. Directing investment only towards commercial districts may therefore widen existing inequalities. Cities that map heat exposure, consult residents and combine physical improvements with public-health measures are more likely to protect vulnerable communities. The evidence suggests that urban heat can be reduced, but only through coordinated and locally appropriate action. Reflective surfaces, vegetation, water-sensitive design and emergency planning should be treated as complementary tools rather than competing alternatives.