Comprensión auditiva TOEFL

🎧 Transcripción de audio

Listen to part of a lecture in an environmental science class. Professor: Today we're going to discuss the concept of 'urban heat islands' and some potential solutions. Urban areas tend to be warmer than surrounding rural areas because of human activities and the prevalence of dark surfaces like asphalt and rooftops that absorb heat. One proposed solution is the installation of green roofs—rooftops covered with vegetation. These roofs can reduce heat absorption because plants reflect more sunlight than conventional materials. Additionally, green roofs help manage stormwater by absorbing rainwater, which reduces the burden on city drainage systems. However, they are not without drawbacks. The initial cost is high, and maintenance requires regular watering and care. Moreover, in very dry climates, the water needed to sustain the plants might outweigh the environmental benefits. Another solution is using cool roofs, which are painted with highly reflective materials. These are cheaper and simpler to install. But they don't provide the added benefits of insulation or stormwater management that green roofs do. So, the choice really depends on the specific climate and budget of the city.