Approach:

Introduction: Briefly tell what Urban Heat Island is. Explain the purpose of Heat Action Plans and how they can be used to mitigate the urban heat island effect.

Body: Evaluate the potential effectiveness of Heat Action Plans in mitigating the urban heat island effect in Indian urban areas

Conclusion: Discuss the future of Heat Action Plans in Indian metropolitan areas.

Answer:

The replacement of natural land cover with impervious surfaces, such as buildings and roads, causes the urban heat island effect. These surfaces absorb and retain heat, making urban areas hotter than surrounding rural areas.

Heat Action Plans are a set of policies and interventions designed to reduce the health impacts of heat waves and mitigate urban heat island effects. The NCT of Delhi has recently developed a Heat Action Plan which includes a heat early warning system, heat risk communication, and heat response measures.

Evaluation of the potential effectiveness of Heat Action Plans in mitigating the urban heat island effect in Indian urban areas:

1. Heat early warning systems can help identify heat waves early and allow for timely action to be taken. For example, the Ahmedabad Heat Action Plan (HAP) has a heat early warning system that uses weather data to forecast heat waves. When a heat wave is forecast, the HAP activates a number of measures, including opening cooling centres and providing transportation to cooling centres for vulnerable populations.
2. Heat risk communication: to raise awareness of the risks of heat waves and how to stay safe. For example, the Delhi HAP has a heat risk communication campaign that targets the most vulnerable populations, such as the elderly, the sick, and the homeless. The campaign includes information on how to stay safe during heat waves, such as staying hydrated, avoiding strenuous activity, and checking on neighbours.
3. Heat response measures can be activated during heat waves to protect vulnerable populations and reduce the risk of heat-related illness and death. For example, the Mumbai HAP has a heat response plan that includes opening cooling centres, providing transportation to cooling centres, and checking on vulnerable individuals. The plan also includes measures to address the urban heat island effect, such as planting trees and increasing green space.
4. Heat adaptation measures can be implemented to reduce the heat island effect and make communities more resilient to heat waves. For example, the Ahmedabad HAP includes measures to plant trees and increase green space. The plan also includes measures to improve the energy efficiency of buildings and to use cool materials for roofs and pavements.
5. Green infrastructure includes measures such as planting trees, creating green roofs, and restoring wetlands. Green infrastructure can help reduce the heat island effect by shading buildings and streets, increasing evapotranspiration, and improving air quality.
6. Cool roofs are made of materials that reflect heat back into the atmosphere. Cool roofs can help reduce the amount of heat that is absorbed by buildings, which can help cool the surrounding air.
7. Ventilation: This includes measures such as improving airflow through buildings and opening windows and doors. Ventilation can help circulate cooler air and reduce the amount of heat that builds up inside buildings.
8. Public awareness: this includes raising awareness of the risks of heat waves and how to stay safe. Public awareness campaigns can help reduce the number of heat-related illnesses and deaths.

There is a growing body of evidence that HAPs can be effective in mitigating the urban heat island effect and protecting public health. For example, a study in Ahmedabad found that HAP was associated with a 30% reduction in heat-related deaths. HAPs are a promising tool for mitigating the urban heat island effect and protecting public health in urban areas in India. By implementing these plans, cities can make their communities more resilient to the impacts of climate change.