It’s a cool, calm, collected drive through the rural backroads of Orange County. A place where fresh air and greenery is in abundance, and you can’t help but roll the windows down, turn up the radio, and take a deep breath. But as the country roads take you to your suburban home, the archways of green begin to crumble and the air begins to take on a hotter tone. Once your home has been reached, the surroundings look anything but green and the air seems anything but fresh. If you have experienced this, as many have within the city, you may be victim of the Urban Heat Island Effect.
The Urban Heat Island Effect is a phenomenon that relates the decrease of greenspace in a city to the increase of urban temperature. In essence, the paved spaces within a city cause urban temperatures to get hot and stay hot.
The Urban Heat Island Effect
The Urban Heat Island Effect is caused by roads, parking lots, buildings, and sidewalks that are often built with materials that like to trap heat. This happens because concrete is slow to heat up and slow to cool down. During the day, the paved areas begin to heat up in the sun and keep releasing heat. Some may experience this when traversing a hot, midday parking lot on the way to their car. However, scorching parking lots are not the only source of unbearable heat. Many parts of the city take on the same tune. As the sun beats down on concrete structures, the structures store the heat and release it little by little. Wind will help cool the city, but many of our dense urban layouts can limit airflow through the city. That can make the cooldown of the concrete last into the night, causing nightly temperatures to rise as well.
This phenomenon is opposite of the cooling effect of greenspaces. For example, when trees shade an area, the sun is deflected and diffused by the leaves above, leaving the ground below to stay cool. But trees are not the only cooling champions. Many plants, from grasses to shrubs, will contribute to the cooling of a space. Greenspace also helps proper airflow. As more plants grow in the same area, the cooling effect begins to draw in more hot air, working like leafy air conditioning for the space.
Why is The Urban Heat Island Effect so important?
It teaches us an important thing about plants. Plants can add more than beauty or wildlife to a space. They can also add comfort and make our parks and backyards much more pleasurable to be in. By adding green to our spaces, we help cool our cities and defend against the hot, stale breeze that can come from too many paved spaces.