A recent study by Climate Trends reveals that elevated summer temperatures significantly exacerbate pollution risks by increasing PM2.5 levels. This new understanding challenges the common perception that severe air pollution is primarily a winter phenomenon in India.
The study underscores that secondary pollutants form through chemical reactions in the atmosphere, leading to a spike in PM2.5 levels during hotter months. Volatile organic compounds (VOCs) play a pivotal role in this process, with their oxidation leading to the creation of secondary organic aerosols (SOAs). Additionally, the reaction of nitrogen oxides (NOx) with hydrocarbons results in the formation of peroxyacetyl nitrate (PAN), a contributor to photochemical smog.
“While we are alarmed by the record-breaking levels of air pollution in winter months, the sudden spike in air pollution in the summer months could harm us in different ways. Understanding the interplay between PM2.5 levels and temperature is crucial for developing effective strategies,” an official remarked. Data from April 2022 to May 2024 highlights a clear correlation between temperature and PM2.5 levels in Kolkata. The PM2.5 concentrations tend to rise during warmer months, particularly from April to May in both 2023 and 2024, coinciding with peak annual temperatures. Conversely, cooler months generally see lower PM2.5 levels, as observed in early 2022 and the latter parts of each year.
Experts emphasise the need for a year-round approach to air pollution control. “Policymakers must undertake measures that reduce sources of air pollution throughout the year and not just mask them during the winter months,” one professor stated. This call to action highlights the necessity of addressing air pollution’s root causes rather than relying on temporary seasonal solutions. The findings from Climate Trends’ study present a compelling case for comprehensive and sustained pollution management strategies. By recognising the role of temperature in exacerbating pollution, policymakers and environmentalists can develop more effective interventions to protect public health and the environment.
This new understanding of the relationship between temperature and PM2.5 levels is crucial for crafting policies that ensure better air quality throughout the year. It underscores the importance of continuous monitoring and proactive measures to mitigate the adverse effects of air pollution, particularly as climate patterns evolve.
