托福听力

🎧 听力原文

Listen to part of a lecture in an environmental science class. Professor: Today we're discussing urban heat islands, a phenomenon where cities are significantly warmer than surrounding rural areas. One major cause is the replacement of natural surfaces like soil and vegetation with materials such as asphalt and concrete, which absorb and retain heat. Another factor is waste heat from buildings, vehicles, and industrial processes. Interestingly, the heat island effect can vary within a city—dense downtown areas are usually hotter than leafy suburbs. To mitigate this, many cities are adopting green roofs, which are covered with plants, and cool pavements that reflect more sunlight. Some researchers also suggest that increasing tree canopy can reduce local temperatures by providing shade and releasing moisture through evapotranspiration. However, these solutions require careful planning and investment. Now, I'd like to discuss a case study from a city that implemented multiple strategies...