AIR POLLUTION is considered to be one of the largest factors contributing to climate change. We are unenlightened that conversely – as climate change also causes air pollution and both can be portrayed as two sides of a coin.
Associate Professor Dr Yusri Yusup, an atmospheric physicist from the field of Environmental Technology based in Universiti Sains Malaysia (USM), who also serves as an air quality expert in the Department of Environment Malaysia shared this opinion with The Petri Dish.
Yusri stresses that before integrating both conditions into a winning combination for climate action, it is crucial to understand climate change and air pollution distinctly because it often leads to misconceptions due to its complex interaction.
“Policy and scientific debates around air pollution and climate change tend to take place separately but tackling both can be an effective climate action,” says Yusri.
According to him, air quality and climate have complex interactions in the atmosphere. Greenhouse gases trap more heat which leads to temperature changes and this subsequently modifies the chemical composition of the atmosphere.
Lending another scenario, he says during heat waves, areas of high pressure create stagnant air that concentrates air pollutants in one area. Prolonged high temperature leads to forest fires, which releases particulate matter into the air.
“Air pollution and climate change are intertwined but are fundamentally different. Climate change is the deviation of temperature and weather from the regular pattern, while air pollution is the presence of substances at harmful concentration levels in the air. The connection is that both conditions regulate the atmosphere additionally, atmospheric conditions that shift due to climate change could exacerbate air pollution phenomena,” elaborates the atmospheric physicist.
Air quality in Malaysia
Yusri says that Malaysia’s air quality is determined based on the new Malaysian Ambient Air Quality Standard.
“This standard has six air pollutant criteria that include particulate matter with the size of less than 10 micrometers (PM10), particulate matter with the size of less than 2.5 micrometers (PM2.5), sulfur dioxide, nitrogen dioxide, ground-level ozone, and carbon monoxide,” explains the expert.
He says the air quality standard sets permissible concentration thresholds on pollutants and plays an important role in determining if a proposed development or industrial activity would degrade the air quality to an unacceptable level.
He further says air quality in Malaysia is determined by using Air Pollutant Index (API) as an indicator at any particular area. The API value is calculated based on the average concentration of the six air pollutants classified in the standard. The API range is zero to more than 300, while below 50 is classified as good and above 100 is unhealthy. On a typical weekday, the API ranges around 20 in Perlis and 70 in Klang Valley.
Malaysia’s air quality is generally below the Malaysian Ambient Air Quality Standard, which means they are good to moderate, but air pollution hotspots still exist in some locations in Malaysia such as Kuala Lumpur, Negeri Sembilan, and Johor Bahru.
The industry that contributes the most to air pollution in Malaysia is the transportation sector followed by the industrial sector.
Touching on mitigation initiatives to monitor air quality, mandatory monitoring of industrial smokestacks, the inclusion of the air pollution impact study in the Environmental Assessment Report and the online reporting of API are being implemented.
Pollutants: Do they warm or cool the surface of Earth?
There is a misconception that all pollutants warm the surface of Earth but there are also a few pollutants that cool down the Earth. Aerosols are tiny particulates in the air that is released through burning fossil fuels which also come from natural resources such as volcanoes, sea salt, and wildfire.
Aerosols get into the atmosphere through dust and it has the potential to change the amount of solar energy reflected away from Earth. However, not all aerosols react the same way with sunlight as sea salt particles reflect sunlight back into space and black carbon particles from burning wood or fossil fuels absorb most of the sunlight that hits them.
Although it has a cooling effect, greenhouse gases remain in the atmosphere for a longer time than aerosols. Thus, the warming effect of greenhouse gases is larger than the cooling effect of aerosols.
Role of an Atmospheric Physicist
“We need more atmospheric and environmental scientists in Malaysia to study the tropical atmosphere to make accurate predictions on the interactions and processes within and around it. Climate actions requires more studies so we can better understand the precise relationship between atmospheric chemicals and climate change. Atmospheric physicists could also play a role as science communicators to create awareness on the atmospheric-related issues through academic programs and public talks,” concludes Yusri.
