- Source – The Hindu
- Link – https://www.thehindu.com/opinion/lead/heat-baked-chennai-can-set-an-example-for-india/article68237181.ece
- Syllabus – GS Paper 03
- Topic – Conservation, Environmental pollution and degradation
What is the issue?
The article discusses how the Urban Heat Island effect makes cities like Chennai hotter than rural areas. It highlights the importance of increasing green spaces, using energy-efficient air conditioning, and adopting other measures to reduce heat and improve city living conditions.
What is the Urban Heat Island Effect?
- In 2023, global temperatures reached record highs, surpassing pre-industrial levels by 45 degrees Celsius and nearing the 1.5°C limit outlined in the Paris Agreement.
- This concerning trend is exacerbated in cities due to the urban heat island (UHI) effect, where concrete structures, paved roads, and limited green spaces trap heat and pollutants, creating significantly higher temperatures compared to rural areas.
- Chennai, among India’s metros, has one of the lowest percentages of green cover, with initiatives like “miyawaki forests” showing promise in greening urban spaces. Under high humidity conditions, a wet-bulb temperature of around 38.5°C is considered critical by the World Health Organization, nearing the limits of human survivability.
- In India, a heatwave is officially declared along coastal areas when maximum temperatures exceed 37°C and are 5°C above normal.
Case study of Chennai
- The coastal city of Chennai faces an additional challenge because of its high humidity.
- This reduces the cooling effect of sweating, which can lead to heat stress, exhaustion and even fatal heat strokes.
- The UHI effect in Chennai further aggravates this problem, adding 2°C to 4°C to the temperatures already increased by the coastal climate.
- This combination of heat and humidity creates dangerous conditions for residents, especially the vulnerable poor, infants and the elderly.
India’s Heat Action Plans:
- India has implemented Heat Action Plans (HAPs) at national, state, and district levels to mitigate heat-related mortality.
- These plans focus on early warning systems, shade shelters, drinking water arrangements, and adjusted working hours for outdoor workers.
- However, these measures, while necessary, are reactive and do not address the root causes of urban heat.
Heat Action Plans for Chennai:
Plan 01-
- To proactively tackle the urban heat island (UHI) effect, Chennai needs to take several steps.
- The Chennai Metropolitan Development Authority (CMDA) has developed heat maps for local planning and actions.
- The Chennai Climate Action Plan (CCAP) suggests ways to mitigate urban heat, though some experts believe it may underestimate causal factors and remedial measures.
Plan 02-
- Increasing green cover is crucial for cooling Chennai.
- Urban forests, parks, and tree-lined walkways release moisture, cool the environment, and improve local microclimates while reducing air pollution and promoting health.
Plan 03-
- Addressing energy efficiency is vital.
- Approximately 50% of Chennai’s summer electricity consumption is from air conditioning.
- Promoting energy-efficient air conditioners, better building insulation, and ventilation can significantly reduce waste heat and energy consumption, cooling urban areas.
Plan 04-
- Additional measures include permeable pavements, increasing shrubs, and applying reflective paint to surfaces.
- Reducing private vehicle use and promoting public transport can further cut urban heat and pollution.
Plan 05-
- Chennai, with its Climate Action Plan, has the potential to serve as a model for India.
- By implementing comprehensive strategies to combat the UHI effect, the city can enhance liveability and contribute to a cooler, sustainable future
