Climate Change Is Blurring the Seasons: Policy Must Catch Up

21 Oct 2026

Tags: Environment   Climate Change   Adaptation strategies

Source: The Indian Express

Context: Despite a rain-deficient monsoon, Mumbai recorded 38°C on October 12, over 5°C above normal. The India Meteorological Department (IMD) attributed this to an anticyclonic circulation and shifting wind patterns, which delayed the sea breeze and reduced natural cooling.

• Climate Change and Seasonal Uncertainty: The episode illustrates how changing climatic conditions can make seasonal transitions less predictable, exposing cities to unusual heat and deteriorating air quality even outside conventional summer months.

Why Did Mumbai Experience Extreme Heat and Pollution?

• Anticyclonic Circulation: Associated with sinking air and atmospheric stability, it can suppress vertical mixing and, under suitable conditions, contribute to stagnant weather and pollutant accumulation.
• Delayed Sea Breeze: Changes in wind patterns delayed the arrival of the cooling sea breeze, allowing temperatures to rise.
• Urban Heat-Island Effect: Concrete buildings, asphalt roads and shrinking green spaces absorb and retain heat, making densely built urban areas warmer.
• Air Pollution: Weak winds and stagnant atmospheric conditions restricted pollutant dispersal, while high temperatures and intense sunlight favoured the formation of ground-level ozone.

Health Impacts of Heat and Air Pollution

• PM2.5: Fine particulate matter penetrates deep into the lungs and can enter the bloodstream, increasing respiratory and cardiovascular risks.
• Ground-Level Ozone: A secondary air pollutant formed through chemical reactions involving nitrogen oxides (NOx) and volatile organic compounds (VOCs) in sunlight; it damages the respiratory system.
• Extreme Heat: Places additional stress on the cardiovascular and renal systems, particularly among people with existing illnesses.
• Vulnerable Groups: Outdoor workers, older people, children and residents of poorly ventilated homes face heightened risks from heat and pollution.
• Winter Heat Risks: Research by the University of Chicago’s Climate Impact Lab, cited in the article, highlights the potential for substantial heat-related health impacts in India during winter, when preparedness may be inadequate.

Air Pollution Control in Mumbai

• Judicial Intervention: The Bombay High Court has expressed concern over deteriorating air quality on multiple occasions. On October 15, while considering firecracker restrictions, it warned that uncontrolled bursting amid rising pollution could turn cities into “gas chambers”.
• Major Pollution Sources: Vehicular emissions, construction activities, road dust, industrial operations and waste burning remain important contributors to urban air pollution.
• Existing Measures: Municipal authorities have introduced dust suppression and real-time air-quality monitoring, but uneven compliance limits their effectiveness.
• Required Improvements: Enforce construction-site dust controls, consistently monitor industrial and vehicular emissions, prevent waste burning and improve public transport. Sustained enforcement is more effective than relying only on emergency restrictions during pollution episodes.

Urban Planning and Nature-Based Solutions

• Green Infrastructure: Expanding tree cover, protecting mangroves and wetlands, and preserving open spaces can help moderate urban heat.
• Cool Roofs: Reflect more sunlight and absorb less heat, reducing indoor temperatures and cooling demand.
• Integrated Approach: These measures must complement, rather than replace, direct reductions in pollution emissions.

Adapting Heat Action Plans

• Beyond Summer: Heat Action Plans (HAPs) must respond to unusually hot October days and unexpected winter heat, rather than relying exclusively on conventional seasonal calendars.
• Improved Warnings: Forecasting and public-health advisories should account for humidity, warm nights, duration of heat exposure and deteriorating air quality.
• Worker Protection: Provide drinking water, shaded rest areas and adjusted working hours for outdoor workers during extreme heat.
• Targeted Outreach: Prioritise older people, children, outdoor workers and residents of poorly ventilated homes.
• Region-Specific Planning: Avoid a uniform national template because geographical and climatic conditions determine how heat and pollution interact in different regions.

Way Forward

• Break Administrative Silos: Integrate climate adaptation, air-pollution control, urban planning and public-health preparedness instead of treating them as separate policy areas.
• Locally Tailored Responses: Each city must assess its own climatic conditions, pollution sources and vulnerable populations to develop effective interventions.
• Preventive Governance: Shift from reactive crisis management to continuous monitoring, source-level pollution reduction and year-round heat preparedness.