Practice Tests
IELTS Reading (AC) Task 1 #80

A. Cities often register warmer temperatures than their rural surroundings, a pattern known as the urban heat island. The contrast arises because streets, roofs, and concrete surfaces store solar energy during the day and release it slowly at night. In many large cities, average summer air temperatures can be three to seven degrees Celsius higher than nearby fields and forests. This persistent warmth reshapes daily life, influences energy use, and poses risks during warm seasons when night time relief is limited.

B. Several mechanisms intensify the effect. Dark construction materials absorb more sunlight than vegetation, while the scarcity of trees reduces shade and evapotranspiration, a natural cooling process where plants move water from soil to air. Tall buildings can slow wind and trap warm air in narrow streets. Waste heat from air conditioners, vehicles, and industry adds further warmth, especially in dense commercial districts where demand for cooling peaks in the afternoon and early evening.

C. The consequences extend beyond discomfort. During a heat wave, elevated night temperatures increase stress on the human body, raising the likelihood of heat exhaustion and heat stroke, particularly among the elderly, outdoor workers, and people with chronic illness. Electricity demand rises as residents run air conditioning for longer hours, which can strain power grids and elevate energy costs. Warmer surfaces also affect air chemistry, encouraging the formation of ground level ozone that irritates lungs and reduces visibility.

D. Mitigation strategies draw on both design and ecology. Cool roofs and reflective pavements return more sunlight to the sky and keep building surfaces cooler. Green roofs and expanded tree canopies provide shade and increase evapotranspiration, which can lower afternoon air temperatures in a neighborhood by one to two degrees Celsius according to field studies in temperate and Mediterranean climates. Parks, ponds, and restored wetlands moderate local microclimates, while lighter colored building materials and permeable surfaces reduce heat storage and improve stormwater management.

E. Effective policy requires careful mapping and equity minded planning. Satellite imagery helps identify hot spots where tree cover is sparse and vulnerable populations face higher risk. Building codes that favor cool materials, incentives for shade trees, and summer preparedness plans can reduce health impacts. Because cities differ in climate, architecture, and energy systems, the best programs combine local measurements with community input. In doing so, urban areas can remain productive and livable while adapting to a warming world.