Rising temperatures contribute to higher ozone levels in atmosphere: UN Report

The recent UN Report highlighting the link between rising global temperatures and increased atmospheric ozone levels, along with a significant 46% rise in worldwide mortality due to ozone exposure between 2000 and 2019, presents a critical intersection of climate change and public health. This finding is not merely an environmental statistic but a stark warning about the compounding crises facing humanity, demanding a comprehensive understanding for competitive exam aspirants.

At its core, the issue revolves around ozone, a gas with a dual nature. While stratospheric ozone, found high in the atmosphere, is beneficial as it shields Earth from harmful ultraviolet (UV) radiation, tropospheric or ground-level ozone is a potent air pollutant. Unlike particulate matter, ground-level ozone is not directly emitted but forms through complex photochemical reactions involving precursor pollutants like Nitrogen Oxides (NOx) and Volatile Organic Compounds (VOCs) in the presence of sunlight and heat. These precursors primarily originate from industrial emissions, vehicular exhaust, power generation, and agricultural activities. The UN report underscores that rising global temperatures accelerate these chemical reactions, leading to higher concentrations of ground-level ozone, especially during heatwaves.

Historically, the understanding of air pollution and its health impacts evolved significantly after events like the Great Smog of London in 1952. While early focus was often on particulate matter and sulfur dioxide, the complexity of photochemical smog, with ozone as a key component, became increasingly evident. International efforts like the Montreal Protocol (1987) successfully addressed stratospheric ozone depletion, but ground-level ozone remains a persistent challenge, now exacerbated by the overarching threat of climate change, which itself is driven by greenhouse gas emissions since the industrial revolution.

Key stakeholders in this complex web include international bodies like the United Nations Environment Programme (UNEP) and the World Health Organization (WHO), which commission these critical reports, set global standards, and foster international cooperation. National governments, such as India's, are crucial in formulating and implementing environmental policies through ministries like the Ministry of Environment, Forest and Climate Change (MoEFCC) and regulatory bodies like the Central Pollution Control Board (CPCB). Industries, particularly those involved in energy, manufacturing, and transportation, are major emitters of ozone precursors and thus have a significant responsibility to adopt cleaner technologies and sustainable practices. The scientific community plays a vital role in researching these linkages, monitoring air quality, and providing data for informed policy-making. Finally, the public, as both sufferers of health impacts and agents of change, forms an indispensable stakeholder, advocating for better policies and adopting sustainable lifestyles.

For India, the implications are particularly severe. With a rapidly growing population, increasing urbanization, and reliance on fossil fuels for energy and transport, India already faces significant air pollution challenges. Major cities frequently feature among the world's most polluted. Rising ozone levels will further compound India's already heavy burden of respiratory illnesses, leading to increased hospitalizations, premature deaths, and lost economic productivity. The 46% global mortality increase due to ozone exposure is a stark indicator of what could worsen in India. Furthermore, ground-level ozone is also detrimental to agriculture, reducing crop yields, which poses a direct threat to food security and the livelihoods of millions of farmers.

India's constitutional framework provides a basis for environmental protection. Article 21, guaranteeing the 'Right to Life and Personal Liberty,' has been expansively interpreted by the Supreme Court to include the right to a clean and healthy environment. Article 48A, a Directive Principle of State Policy, mandates the State to 'endeavour to protect and improve the environment and to safeguard the forests and wildlife of the country.' Furthermore, Article 51A(g) enshrines as a Fundamental Duty for every citizen 'to protect and improve the natural environment including forests, lakes, rivers and wildlife, and to have compassion for living creatures.' To operationalize these principles, India has enacted crucial legislation like the Environment (Protection) Act, 1986, and the Air (Prevention and Control of Pollution) Act, 1981. Policy initiatives like the National Clean Air Programme (NCAP) aim to reduce particulate matter pollution, which indirectly helps in reducing ozone precursors, and the Bharat Stage Emission Standards for vehicles are steps towards mitigating vehicular pollution.

This issue connects to broader themes of environmental governance, public health, sustainable development, and international relations. It highlights the interconnectedness of climate action (SDG 13), good health and well-being (SDG 3), and sustainable cities and communities (SDG 11). The challenge for India, and indeed the world, is to balance economic development with environmental protection, fostering 'green growth.'

Looking ahead, the future implications are clear. Without aggressive mitigation strategies, the health burden from ozone exposure will likely continue to rise, particularly in vulnerable populations. This necessitates a multi-pronged approach: accelerated transition to renewable energy sources, stricter emission norms for industries and vehicles, promotion of public transport and electric vehicles, sustainable agricultural practices, and robust public health infrastructure capable of managing respiratory ailments. International cooperation, as envisioned by agreements like the Paris Agreement, remains crucial for tackling climate change, which is intrinsically linked to the ground-level ozone problem. India must strengthen its air quality monitoring networks, invest in research on climate-ozone interactions, and implement integrated policies that address both climate change and air pollution simultaneously for a healthier and sustainable future.