Book 7, Question 68
Why Do Cities Feel Warmer than Countryside?
Cities are often warmer than the countryside around them. Pavement, roofs, and buildings soak up the Sun's heat and release it slowly in the evening. Scientists call this the urban heat island effect, and it makes city nights stay warmer.
From the book
Page from A Million Whys Book 7
More fun facts
- Cities can be up to 10 degrees Fahrenheit warmer than the natural land around them.
- Trees and plants cool the air with shade and by releasing water. Cities with fewer trees lose that cooling.
- Heat from cars, factories, and air conditioners adds extra warmth to cities.
- The difference between city and countryside is often biggest on calm, clear evenings.
- A U.S. Geological Survey study of 50 big U.S. cities found their surfaces averaged about 5 degrees Fahrenheit hotter than nearby non-city areas.
- Heat islands can happen all year, during the day or at night.
Sources: UCAR Center for Science Education, U.S. Geological Survey
Questions kids ask
How much warmer can a city be?
Up to about 10 degrees Fahrenheit warmer than the land around it.
How do trees cool a city?
They give shade and release water from their leaves, which cools the air.