Urban Heat Island effect makes cities like Chennai hotter than rural areas

Source: The post Urban Heat Island effect makes cities like Chennai hotter than rural areas has been created, based on the article “Heat-baked Chennai can set an example for India” published in “The Hindu” on 1st June 2024.

UPSC Syllabus Topic: GS Paper 3– Disaster management

Context: 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 (UHI) effect?

The Urban Heat Island (UHI) effect refers to the phenomenon where urban areas are significantly warmer than their rural surroundings due to human activities. Here are key points about the UHI effect:

Urban areas like Chennai experience higher temperatures, by about 2° to 4°C, compared to nearby rural areas.

Structures such as concrete buildings and tarmac roads absorb and retain heat, exacerbating the temperature rise.

The lack of green spaces and the heat from air conditioners and vehicles add to the UHI effect.

Nighttime in cities can be especially hotter, trapping heat within the urban environment.

What are the initiatives taken by the Government to overcome this?

1. India has national, state, and district-level Heat Action Plans to reduce heatwave impacts.
2. These include early warnings, staggered work hours, shaded areas, and provision of drinking water and oral rehydration salts.
3. Urban Planning: The Chennai Metropolitan Development Authority (CMDA) is commissioning detailed heat maps for better planning and intervention strategies. These actions aim to mitigate heat effects and improve urban liveability while moving towards sustainable development goals.

For detailed information on Heat Action Plans (HAP) read this article here

What should be done to reduce UHI?

1. Increase Green Cover: Expanding urban forests, parks, and green spaces, which cool the environment through evaporation and provide shade.
2. Energy-Efficient Air Conditioning: Encouraging the use of energy-efficient air conditioners that produce less waste heat.
3. Improve Building Design: Constructing buildings with materials and designs that naturally keep interiors cool.
4. Reflective Surfaces: Applying reflective paint on roofs, walls, and streets to reflect sunlight and reduce heat absorption.
5. Enhance Public Transport: Reducing reliance on personal vehicles by improving public transport systems, including electric buses.

6.Permeable Pavements: Installing permeable pavements that absorb less heat and allow water to permeate, cooling the environment.

Question for practice:

Evaluate the effectiveness of increasing green cover, promoting energy-efficient air conditioning, and improving building design in reducing the Urban Heat Island effect in cities like Chennai.