長文読解（人文系・自然科学系の文章）- 問題37

The concept of urban heat islands has become increasingly important as cities continue to expand worldwide. An urban heat island occurs when a metropolitan area becomes significantly warmer than its surrounding rural areas due to human activities and infrastructure. This phenomenon is primarily caused by the replacement of natural land cover with concrete, asphalt, and buildings that absorb and retain heat more effectively than vegetation.
Research conducted in major cities like Tokyo and New York has shown that urban areas can be 2-5 degrees Celsius warmer than nearby rural regions. The effects are most pronounced during nighttime when natural surfaces cool down rapidly, but urban materials continue to release stored heat. This temperature difference not only increases energy consumption for air conditioning but also affects local weather patterns and air quality.
To combat urban heat islands, cities are implementing various strategies including green roofs, urban forests, and reflective building materials. Singapore has emerged as a leader in this field, requiring new buildings to incorporate green elements and achieving a 2-degree reduction in certain districts. These initiatives demonstrate that thoughtful urban planning can effectively mitigate the heat island effect while improving residents' quality of life.