The link between air pollution and climate change

There is a clear connection between poor air quality and climate change. Air pollutants and greenhouse gases are often emitted at the same time, and many air pollutants have direct or indirect climate effects. By reducing air pollution, we preserve and protect our climate. In a more recent article, we also look at how climate change makes air pollution worse.

The effects of air pollutants on the climate

When talking about climate change, greenhouse gases (GHGs) are what first comes to mind. These are compounds that create what is known as the greenhouse effect by trapping the sun’s heat in the earth’s atmosphere and preventing it from returning to outer space. The gas most commonly produced by human activities is carbon dioxide (CO₂). CO₂ mainly stems from the extraction and burning of fossil fuels like coal and oil and is responsible for 64% of man-made global warming. Carbon dioxide can remain in the atmosphere for thousands of years, making its impact on the environment all the more significant. 

Aside from carbon dioxide, the other main contributors to climate change are compounds that belong to a group called short-lived climate pollutants (SLCPs), such as black carbon (BC) – a component of particulate matter (PM_2.5), methane (CH₄), and ground-level ozone (O₃). These pollutants do not last as long as carbon dioxide in the atmosphere, but their warming potential is higher, causing harmful effects to the environment. 

Black carbon, also called soot, is formed through the incomplete combustion of fuels. While it is short-lived with a lifetime of 4-12 days, it has a warming impact that is 460-1,500 times higher than carbon dioxide on the climate. This is due to its ability to absorb incoming solar radiation and converting it into heat, thus effectively warming its surroundings. Black carbon also reduces the surface albedos of snow and ice crystals and heats them, thus making them susceptible to melting. When embedded in clouds, soot dims the sunlight that reaches earth by absorbing it, causing changes in cloud and rainfall patterns which affect both ecosystems and human livelihoods.  

Methane is a greenhouse gas with a lifetime of 12 years. Compared to carbon dioxide, its warming impact is 84 times higher over a 20-year period and 28 times higher over a 100-year period. Methane serves as the main precursor of ground-level ozone, a major air and climate pollutant. 

Ground-level ozone is a secondary gas formed by the reaction of sunlight with other air pollutants like carbon monoxide (CO), methane, nitrogen oxides (NO_x), and non-methane volatile organic compounds (NMVOC). It has a lifetime of a few hours to a few weeks and is a strong greenhouse gas. Not only does it contribute to global warming, it also impacts atmospheric circulation, cloud formation, evaporation rates, and precipitation levels, thus contributing to climate change. Ground-level ozone also has strong negative health effects on humans.

Improving air quality and combating climate change

Studies have found that cutting SLCP emissions is key alongside limiting greenhouse gas emissions in order to achieve the Paris Agreement of limiting the global temperature to less than 2˚C. To that end, the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) have identified a set of measures for reducing up to 90% of SLCP emissions using already existing technologies and practices. Doing so could drop the warming expected to occur in the next few decades by 0.6˚C and also prevent 2.4 million annual outdoor air pollution deaths by 2030.

Targeted action is key: In order to effectively implement the aforementioned recommendations from the UNEP and the WMO, comprehensive data is required. Hyperlocal air quality data from sensors, satellites and other data sources can enable decision makers to identify pollution hotspots and implement targeted action, as well as track their successes. The overlap between SLCPs and air pollutants means: Clean air actions are climate actions!

Breeze Technologies’ AI-powered air quality sensors provide accurate, real-time air quality and climate data from the indoor and outdoor environment. Our Environmental Intelligence Cloud collects, processes and provides immense amounts of information, including on carbon dioxide, particulate matter, and ozone levels. This data can be leveraged to determine clean air actions and be used to rate their efficiency and effectiveness, making targeted action possible. It can also be integrated in novel smart city and smart industry applications. Our initiative is global and far-reaching, with a network of municipal and national governments, NGOs, corporates, research institutes, and individual citizens connected through implemented clean air actions and our citizen platform. 

Only together, we can create healthier cities and build a more sustainable future⁠ – health- and climate-wise⁠ – for all.