The La Nina and North India’s pollution

Delhi’s air quality faces new challenges this winter due to the delayed onset of La Niña and the late retreat of the monsoon. These climatic conditions could exacerbate pollution levels, particularly with potential stubble burning contributing to the problem. Recent research highlights the interplay of climate change, La Niña, and air quality, emphasizing the need for a shift in policy focus.

Impact of Climatic Conditions

• Delayed Monsoon Retreat: The prolonged presence of high humidity and calm winds following the late retreat of the monsoon can lead to reduced atmospheric mixing. This stagnation is likely to trap pollutants, raising levels of 5 and PM10 in the air.
• Uncertain La Niña Development: La Niña typically enhances wind strength and atmospheric circulation, which can disperse pollutants. However, its late arrival, anticipated between September and November 2024, means that neutral conditions may worsen pollution in northern India during early winter.
• Stubble Burning Influence: The prevalence of north-north-westerly winds increases the impact of stubble burning from Punjab and Haryana on Delhi’s air quality. Without La Niña conditions, the pollution from these practices could significantly degrade air quality in the capital.

Potential Future Scenarios

• Late Onset Effects: Should La Niña develop in December, it might improve air quality due to stronger winds and reduced pollutant accumulation. However, it could also lead to a longer, more severe winter, trapping pollutants and limiting dispersion.
• Comparison with Early Onset: Had La Niña settled in by July, predictions suggest a 20% increase in winter PM2.5 pollution in peninsular India, while an earlier onset could have benefited northern regions, improving air quality.
• Persistent Challenges Ahead: Even with potential improvements later in the winter, ongoing issues related to air quality will remain problematic for Delhi and northern India. The interplay of climatic factors necessitates continued vigilance and adaptive strategies.

Need for Comprehensive Policy Shift

• Holistic Approach to Air Quality: Researchers advocate moving beyond localized emission-centric strategies to incorporate broader meteorological and climatological factors. Understanding larger airsheds and their influences on air quality is crucial.
• Integration of Scientific Insights: There is a call for integrating scientific research into policymaking to address the multifaceted issues of air pollution, considering both local and regional sources of emissions. Health-centric measures should be prioritized.
• Mitigation in the Context of Climate Change: As climate change increasingly influences air pollution patterns, there is a pressing need for rigorous mitigation strategies that encompass both anthropogenic emissions and broader climatic uncertainties.

Practice Question

Q. Discuss the implications of climate change on air quality in India, particularly in the context of La Niña and its effects on winter pollution levels. What policy measures should be adopted to mitigate air pollution in urban areas like Delhi?