Our roads also contribute to global warming. Black asphalt, as we all know, has long been the primary material for the surfaces of the roads we travel every day. Soon, however, we will say goodbye to black pavement, but what is the motivation that led to the idea of replacing it with blue?
About Global Warming
Climate change, also known as global warming, is a gradual increase in the average temperature of the Earth. This warming is largely caused by human activities that release greenhouse gases such as carbon dioxide (CO2), methane, and nitrous oxide into the atmosphere. These gases trap the sun’s heat, creating a greenhouse effect that increases global temperatures.
Some of the causes that trigger global warming are:
Coal, oil, and natural gas release large amounts of CO2 into the atmosphere when burned for energy. Forests absorb CO2 from the atmosphere, so cutting them down reduces the planet’s ability to retain these greenhouse gases. Agricultural activities such as raising livestock and using fertilizers release methane and nitrogen oxides into the atmosphere.
The average global temperature has risen by about 1 degree Celsius since pre-industrial times and will continue to rise. In addition, global warming is increasing the frequency and intensity of severe weather events (such as hurricanes, floods, droughts, etc.).
Bottom line: switching to renewable energy sources like solar and wind would improve energy efficiency and reduce dependence on fossil fuels. Protecting forests could go a long way in removing CO2 from the atmosphere. In short, living a more sustainable lifestyle means reducing global warming.
Black asphalt replaced by blue, here’s why
With the ever-increasing global temperature, black asphalt is no longer suitable for such climatic conditions. This type of road surface actually absorbs the heat of the sun, making the ground very hot for both drivers and pedestrians or cyclists. This problem occurs especially in areas where the climate is really intense and muggy.
For this reason, in order to eliminate the problem, in some places the black asphalt has been replaced with blue paint. The latter is able to reflect the sun, thus making the streets cooler and more pleasant.
Several cutting-edge solutions have been adopted to reduce the risk of illness or fainting due to the extreme heat and humidity during the 2022 FIFA World Cup in Qatar, one of the hottest countries in the world. Among the various solutions, one in particular has proven to be the most interesting and effective: replacing the black asphalt with the color of the blue paint on Abdullah Bin Jassim Street, one of the main roads in Doha, located in the busy area near Waqif Soug.
Blue asphalt
The ultimate goal of this experiment was to test whether it was possible to reduce the production of solar radiation from the black tar and lower the high temperature. The road was coated with a film about 1 mm thick containing a particular ceramic shade with heat-reflecting properties. This experiment lasted about 16 months, so a long enough time to obtain reliable results. In fact, the temperature recorded on that road was 20 degrees less than other roads in the city.
In short, this resolution turns out to be really effective and extraordinary as it can have a great positive influence on the life of the people, promoting rapid relief in very hot summers and at the same time reducing the risk of illnesses.
Advantages and disadvantages of blue asphalt
Replacing black asphalt with blue asphalt has its advantages and disadvantages:
Advantages:
Reduces urban heat island: Blue asphalt reflects more sunlight, which reduces the temperature in cities and the impact of the heat island. This can also reduce energy consumption for air conditioning and improve air quality. Improve road safety: Blue can improve road safety by increasing visibility, especially for cyclists and pedestrians. Aesthetic beauty: Blue asphalt can enhance the beauty of a city by giving streets and pedestrian areas a more attractive and well-maintained appearance.
Disadvantages:
Higher cost: Blue asphalt is usually more expensive than black asphalt, due to the added special hues and other special features. Resistance and lifespan: Blue asphalt may have less wear resistance and durability than black asphalt and require more maintenance. Environmental impact: The production of blue asphalt has a greater impact on the environment. This obviously depends on the pigments used and the production process. Special waste: Disposing of blue asphalt at the end of its life cycle is more difficult and expensive.
Another city where blue asphalt was used is Los Angeles, California. The project was called “Cool Street”. Some streets were paved with blue asphalt to reduce the heat island effect of the city and improve the quality of life in the area. And again, the initial results of this project showed significant reductions in road surface temperatures and improved thermal comfort for pedestrians.
In short, the decision to replace black with blue asphalt must be made by carefully weighing the advantages and disadvantages in the specific context of each city. In addition to the points listed above, it is also important to consider local laws, community expectations, and financial availability.
