Model Answer

Urban Heat Island refers to higher temperatures in cities than surrounding rural areas. Rapid construction, loss of natural spaces and changing urban form are intensifying heat stress in Indian cities.

How Urban Planning Increases Heat Stress

1. Loss of greenery reduces shade and evapotranspiration. e.g: Conversion of urban forests and open spaces into built-up areas.
2. Excessive concretisation creates heat-absorbing surfaces. e.g: Asphalt roads and concrete pavements.
3. Blocked wind corridors reduce natural ventilation due to dense and poorly planned construction.
4. Loss of water bodies removes natural cooling systems. e.g: Encroachment of urban lakes and wetlands.
5. Poor building design increases heat absorption and dependence on air-conditioning.
6. Urban sprawl replaces vegetation and agricultural land with impervious surfaces.
7. Transport emissions and air conditioners release additional anthropogenic heat.

Measures for Heat-Resilient Cities

1. Protect and expand urban forests, parks and tree corridors. e.g: AMRUT urban green spaces.
2. Preserve ventilation corridors through appropriate building height, orientation and street design.
3. Restore lakes, wetlands and blue-green infrastructure.
4. Promote cool roofs and reflective surfaces. e.g: Ahmedabad Heat Action Plan.
5. Increase permeable surfaces and reduce unnecessary concretisation.
6. Prepare ward-level heat maps and integrate heat mitigation into Master Plans.
7. Strengthen Heat Action Plans with early warnings and cooling centres.

Urban heat is partly a consequence of planning choices. Climate-responsive design integrating greenery, water bodies and natural ventilation can make Indian cities cooler, healthier and more resilient.