Did you know that 80% of Americans live on islands? These may not be the islands surrounded by sand and water, but instead these are urban heat islands. As the human impact on the environment continues these islands become more and more important to us. First let’s dig into the basics though and start by asking today’s big question, what is a heat island? Listen to this Question Your World radio report produced by the Science Museum of Virginia to find out.
A long time ago all of our urban areas were just nature. Grass, trees, rivers, flower beds, and other natural aspects filled our landscape. The land itself evolved this way based on the life forms here and ultimately the overall relationship to the sun. As humanity grew and started to urbanize the landscape we began to alter the balance between these regions and the sun. Now we live on a planet that is home to 7.4 billion people and growing. Much of our world’s human population lives in urban areas. Some are dense, while others sprawl out, but regardless this is the build world that we are living in.
Consider for a moment the roadways and parking lots that you see every single day. These become places where the falling rain is diverted into collection areas and ultimately put back into our rivers and streams. In a natural setting this water would interact with the environment and ultimately evaporate. The evaporation brings a little bit of cooling to the area. As we continue to develop our urban areas we continue to reduce the amount of cooling we experience due to evaporation. This helps make our urban areas into little pockets of heat, also known as heat islands.
In addition to this, we’re creating buildings which are able to trap the heat from the day time and then release is back into the atmosphere at night. This is another example of how our altering the landscape further adds heat back into the city. Places like the humid south especially have to find ways to divert the hot air away at night to help keep our urban areas cool.
This problem is not just for those folks that prefer cooler temperatures. As extreme heat event increase in frequency so does the threat of heat caused illnesses and health conditions. There are many individuals that suffer from heat related problems in terms of their health and vitality. In fact, excessive heat events are the primary cause of weather related health problems. As we continue to expand our population and urban areas, these issues need to be taken into consideration if we want to keep our cities as safe places for our populations to reside within.
Fear not Virginians, scientists suggest a few ways to help us off set the impact of our heat islands. We could plant more urban trees. A city with more trees would help reduce the heat impact by providing shade, helping keep the roads, sidewalks, and other covered areas a little bit cooler. We can also use reflective or vegetated roofs at our homes and businesses. This is a simple and eco-friendly way to help our sun soaking surfaces to be a bit cooler and help our cities have an opportunity to cool down at night as well. An open dialogue with local lawmakers and urban planners would also be a great way to keep this topic on their minds as decisions are made for expanding areas, new infrastructure, and address human health overall.
With out collective actions we could make some big and small changes to ensure that our heat island won’t be in hot water.