Multiple Choice, Multiple Answers

Read the passage and select ALL statements it supports.

When a city replaces dark asphalt and bare rooftops with lighter, more reflective surfaces, its summer temperatures can fall measurably. This is the logic behind 'cool roof' programmes now spreading through hot cities. Dark materials absorb sunlight and radiate it as heat, raising local air temperatures in what is called the urban heat-island effect. Reflective coatings bounce a larger share of sunlight back to the sky, keeping buildings cooler and cutting demand for air conditioning. The savings are not trivial: lower cooling bills reduce strain on power grids during heatwaves, when blackouts are most likely. Critics note, however, that reflective surfaces can increase glare and offer little benefit in cold-winter climates.