Every year on September 7th, the world faces the dangers of air pollution and unites to create better air quality on the ‘International Day of Clean Air for blue skies’. Since its official establishment at the United Nations (UN) General Assembly in 2019, this commemorative day has established itself as a core venue to remind humanity of the preciousness of air and urge action for a sustainable future. In particular, it holds deep significance both domestically and internationally as the first official UN commemorative day proposed and adopted by the Republic of Korea. Today in 2026, regardless of whether in global megacities or rural areas, the air we breathe still faces a colossal threat, and invisible toxic substances rob countless individuals of their lives on their precious homelands.

Air is the most essential resource shared by all living creatures on Earth. However, humanity has lived while forgetting the ecological value of the atmosphere. According to the latest environmental reports from organizations such as the World Health Organization (WHO) and the United Nations Environment Programme (UNEP), millions of premature deaths occur worldwide every year due to polluted air. Statistics from major institutions, including the State of Global Air Report, clearly show that air pollution goes beyond causing mere inconvenience and is the greatest enemy threatening public health. In particular, damage is concentrated around low- and middle-income countries, demanding urgent resolution from the dimension of environmental justice.

As the main culprits of air quality deterioration, harmful gases such as nitrogen dioxide ($NO_2$) and ozone ($O_3$), alongside fine dust commonly referred to as particulate matter ($PM_{2.5}$), are targeted. These ultra-fine substances penetrate deep into the human lungs through the respiratory tract and spread throughout the body via the bloodstream. Consequently, they induce or worsen respiratory diseases such as chronic obstructive pulmonary disease and asthma, cardiovascular diseases like angina and stroke, and fatal lung cancer. Experts warn that air pollution is a major factor that collapses individual immune systems and shortens life expectancy.

This problem is not limited to human health alone. Air pollution possesses the destructive power to disrupt the balance of the global ecosystem as a whole. Acid rain and rising ozone concentrations hinder the growth of crops and sharply reduce yields, threatening food security and damaging the diversity of forests and aquatic ecosystems. Furthermore, air pollutants are closely connected to climate change. Short-lived climate pollutants, such as methane or black carbon, are main culprits accelerating global warming. Therefore, reducing air pollution is the path to responding to the climate change crisis and serves as the key to simultaneously solving two global challenges.

Looking at the facets of emission sources, the combustion of fossil fuels, indiscriminate industrial activities, a car-centric transportation system, and massive wildfires made frequent by the climate crisis are cited as major causes. To solve this, governments and the international community around the world are hurrying their energy transition policies. Moving away from a coal- and oil-centric economic structure to expand renewable energy such as solar and wind, and building eco-friendly public transportation networks have emerged as national tasks. Moreover, institutional devices that utilize cutting-edge digital technology to monitor air pollutants in real time and strictly regulate emitting companies are trending toward reinforcement.

Then, can this problem be solved just by governments and corporations moving? Experts emphasize that the participation of individuals and local communities is essential. This is because small practices in daily life can gather to lead to massive changes. Reducing the use of private cars and using public transportation or bicycles, increasing energy efficiency at home and reducing unnecessary power consumption, and behaviors aiming for resource recycling and eco-friendly consumption all serve as priming water to purify the air. At the local level as well, we must actively support projects to increase green spaces within urban areas and create urban forests.

Ultimately, the International Day of Clean Air for blue skies in 2026 demands global solidarity from us beyond simple alertness. The right to breathe clean air is not a privilege, but a fundamental human right that all humans must enjoy. The work of returning polluted skies back to blue is the most urgent and sacred duty to be handed down to future generations. When the strong policy will of the government, the responsible eco-friendly transition of the industrial sector, and the conscious behavioral changes of individual citizens become a trinity, can we finally breathe healthily beneath truly blue skies cleared of exhaust fumes and smog.