There have been many studies that show concrete and asphalt and Urban Sprawl increase the temperatures of our Cities and our World!
The Urban Heat Island (UHI) effect is a huge topic.
There is study after study devoted to investigating how it occurs and how much it has increased over time. The solutions or our abilities to control or reduce the heat build up in our cities varies greatly. Most average americans living in the city do not give it much thought, yet the impacts that they and their families will have to overcome are great. The ugly impacts of the UHI that we have to deal with are extended heat waves and air pollution episodes!
Gratefully, there are many scientists looking at this issue. Arizona State Universities School of Sustainability is one of the institutions that is concerned.
Scientists at ASU, want to study how to reduce this temperature by various construction and agricultural means. For Phoenix, Arizona, this may mean too little too late…but if you have been there during the summer over the past decade or so, it’s worth the try.
There are numerous techniques for us to focus on in order to slow down this phenomena!
For the everyman, they should consider the various techniques available to them and implement when able to. To the politicians, especially in Arizona, take a look at the numbers and work together to help enact change!
From Greenbelts, to porous asphalt, to the color of your roof, city areas that are susceptible extreme heat need to pay attention to this. Scientists, Engineers and Planners have know about these techniques for a long time. The problem is as in most things is money, understanding and whether or not regulations can be used to make this happen.
As climates warm and cities grow larger, more attention must be paid to using modern construction techniques and move away from heat sinks that only will exacerbate the heat issues. Phoenix, Las Vegas, El Paso, Dallas take heed! Not only will new construction need to be modified, these techniques must be used when re-asphalting, re-modeling, and any other type of urban renewal takes place.
The costs of not doing anything are great. Cities will get hotter and hotter, infrastructure will suffer, electricity will be in demand as prices go higher, and some areas may not be inhabitable for those who cannot afford to live there!
Here are a few methods that are known to work;
Greenbelts and Sustainability
Greenbelts have been around for years. The UK was the original greenbelt and park builders. Their concept that it humanized and increased values in their communities is well documented. Many US developers use them as golf courses, drainage ways, parks, walking trails and for general aesthetics within their developments. Little did they know how important a role they could play.
The Journal of the American Meteorological Society published a recent 2012 article on the role of urban tree canopies (greenbelts) and natural surfaces on the Urban Heat Island effect (UHI).
Cool Paves – Porous Asphalt
One of the major causes of Urban Warming is the constant construction of roads and parking lots. These heat sinks can be moderated through the use of Porous Asphalts.
Costs were originally higher than regular asphalt, but in recent years has dropped considerably.
Cool Roofs – Reflective Surfaces
The use of light colored roof material and green roof benefits (reflective surfaces) are very important to consider in larger urban areas but have found to vary from place to place.
“the performance of urban adaptation technologies can counteract this increase in temperature, but also varies seasonally and is geographically dependent.”
Read the ASU School of Sustainability’s article and other links at the site below;
One study by the Lawrence Berkeley Laboratory and published in the Energy and Buildings Journal have found that white roofs are three times more effective than green roofs in fighting climate change. Read the article at the following link;
The use of reflective surfaces in reducing the Heat Island Effect are considered Geo-Engineering. Geo-engineering in roofing as explained in wikipedia is a simple concept.
The benefits of cool roofs are many;
- Reduced building heat-gain, as a white or reflective roof typically increases only 5–14 °C (10–25 °F) above ambient temperature during the day
- Savings of up to 15% the annual air-conditioning energy use of a single-story building
- Extended service life of roofs
- Improved energy efficiency of roofs, especially when there isn’t adequate insulation provided in the roof envelope
- Improved thermal comfort in buildings that do not have air conditioning
- Help in mitigating the urban heat island effect.
- Reduced air pollution and greenhouse gas emissions, as well as a significant offsetting of the warming impact of greenhouse gas emissions.
What can we do as individuals?
1) Elect responsible politicians is the first thing that comes to mind when you are talking about large infrastructure items. It may cost more, but the issue is not cost. The issue is about can we sustain our way of living in our urban areas!
2) Spread the word. Talk about the issues with your neighbors. Educate them as needed. Educate yourself for that matter. There is a tremendous amount of information on the Urban Heat Island on the web!
3) Adapt your living area; Plant more trees, replace a dark roof with a light one, add more insulation to your home, use sunblocking shades or films to keep heat from coming in your home!
Work together to make our cities a better place.
If not you, who? If not now, when?