Study: The temperature in the city of Riyadh can be reduced by 4.5 degrees

Arabia Weather - The strategy revealed by the international team of researchers in the new scientific study is considered an important step towards reducing heat in major cities with a hot desert climate. Through the use of light-reflecting coatings and the planting of irrigated green spaces, positive effects on temperatures in cities are achieved, reducing global warming and improving the quality of life in these urban areas.

This study is the first of its kind to seriously address the application of innovative technologies to reduce heat in hot cities, and offers a promising solution to the challenges these cities face in the face of rising temperatures and their harmful effects on the environment and public health. In this context, the cooperation of universities and research institutions with local authorities appears effective in developing sustainable solutions to global environmental challenges.

Heat island phenomenon within cities

A drawing of the heat island phenomenon over major cities (University of Michigan)

Some studies have shown, according to a report published on Earth.org, that the heat island effect can cause urban temperatures to increase by up to 7°C during the day and 12°C at night compared to rural areas. This rise in temperatures can result in a deterioration in air quality and an increase in the concentration of ground-level ozone as well as other pollutants.

Extreme urban heat is estimated to affect more than 450 cities worldwide, increasing demands on energy consumption and negatively impacting public health, leading to increased rates of heat-related morbidity and mortality.

In the Saudi capital, Riyadh, maximum temperatures exceed 50 degrees Celsius during the summer, making it one of the hottest cities in the world. The combination of rapid urbanization and climate change is increasing temperatures, with resulting increases in energy consumption and adverse health effects.

Supercooling materials and irrigated trees to reduce heat

Some studies have shown, according to a report published on Earth.org, that the heat island effect can cause urban temperatures to increase by up to 7°C during the day and 12°C at night compared to rural areas. This rise in temperatures can result in a deterioration in air quality and an increase in the concentration of ground-level ozone as well as other pollutants.

Extreme urban heat is estimated to affect more than 450 cities worldwide, increasing demands on energy consumption and negatively impacting public health, leading to increased rates of heat-related morbidity and mortality.

In the Saudi capital, Riyadh, maximum temperatures exceed 50 degrees Celsius during the summer, making it one of the hottest cities in the world. The combination of rapid urbanization and climate change is increasing temperatures, with resulting increases in energy consumption and adverse health effects.

Supercooling materials and irrigated trees to reduce heat

In the new study, the researchers conducted comprehensive heat mitigation simulations in the Al-Masif region of Riyadh, which included evaluating the energy performance of 3,323 urban buildings. The simulation included experimenting with 8 different cooling scenarios, with the aim of determining the optimal strategies to reduce temperatures in the city and reduce energy needs.

According to a statement published on the University of New South Wales website, the models - which relied on the use of heat-modifying materials developed by the researchers as well as certain types of plants - revealed the possibility of reducing outdoor temperatures in the city by up to 4.5 degrees Celsius during the summer. The results also showed the possibility of increasing the energy efficiency used in cooling by up to 16%.

The recommended scenario for cooling the city of Riyadh includes increasing the number of irrigated trees to more than double their current number, with the aim of improving the effect of water evaporation from these plants (transpiration) on cooling processes.

The strategy also includes the use of supercooling materials applied to the roofs of buildings. These materials are considered a type of radioactive coatings that have appeared in recent years. They contain materials such as chromium and fluorine and act as light reflectors.

A previous study conducted in the Indian city of Kolkata showed that these materials are able to maintain a temperature of only 25 degrees Celsius when the ambient temperature reaches 42 degrees Celsius. In addition, these materials can provide free cooling or even heating of buildings when used as passive components integrated into the building envelope, or as active devices to provide free pre-cooling and ventilation.

The study's authors warn that ill-considered implementation of urban cooling techniques that are not based on scientific basis, such as the use of non-irrigated green spaces, may lead to a significant increase in city temperatures.

Improving the quality of life and reducing the concentration of pollutants

Professor Santamores, professor of science at the University of New South Wales and supervisor of the study, confirmed in a statement to Al-Bayan that implementing the right combination of the proposed cooling technologies can reduce the ambient temperature, which improves the quality of life of the population and reduces health problems resulting from extreme heat. He explained that this combination allows for reducing the concentration of pollutants and improving human productivity. Previous research has indicated that implementing similar cooling strategies in other cities could help reduce heat-related deaths.

The study's simulation showed the impact of the proposed cooling scenario on energy use in all buildings included in the study, and that improving insulation in windows and ceilings could reduce the demand for energy consumption allocated to cooling by up to 35%. Santamores stressed that this significant reduction in energy needs will contribute to reducing the costs associated with cooling in the city of Riyadh, which will improve the quality of life for its residents.

In the near future, the research team aims to cooperate with the Royal Commission in Riyadh to implement the designed heat reduction plan, which is considered the largest of its kind in the world.

Source: Al Jazeera