The Telangana Socio-Economic Outlook 2025 report reveals that Hyderabad is experiencing increased nighttime heat stress due to the urban heat island effect.
What is urban heat island (UHI)?
The UHI effect is a climatic phenomenon observed in urban areas, where temperatures are significantly higher than in surrounding rural areas. This discrepancy in temperature is attributed to human activities and urban development, which alter land surfaces and environments.
Causes of Urban Heat Island
- Use of Heat Absorbing Materials: Materials such as concrete and asphalt absorb heat during the day and release it slowly. It causes temperatures to remain elevated, especially at night.
- Inappropriate Construction: When buildings are adjacent to each other, it limits airflow and creates heat-trapping spaces between structures, causing higher temperatures.
- Absence of Greenery: The absence of plants, trees, and green spaces reduces natural cooling through shade, worsening the effect.
- High Energy Demands: Cities have higher energy demands (transportation, industrial processes, and air conditioning), which release heat into the air.
- Presence of Pollution: Urban heat islands have poorer air quality because more pollutants get trapped in the city. Warm water from cities also harms the quality of nearby streams, affecting the plants and animals living there.
Effects of Urban Heat Island
Health Hazards: Heat stress continues to build, increasing the risk of heat-related illnesses and even death. It poses a grave risk to the lives of the elderly, babies, pregnant women, those who live in slums, and work outdoors.
Environmental Hazards: It contributes to global warming by increasing overall temperatures in urban areas and beyond.
- They lead to lower air quality due to increased fossil fuel consumption, and the pollution in the region makes water bodies polluted.
- Summer nights now offer little respite from the searing heat of the day, with cities across climatic zones not cooling down at the rate they once did.
- Urban heat islands could lead to temperature differences of up to six degrees Celsius within a given area or neighbourhood.
Power Outages & Increase in Energy Cost: All this also puts a strain on energy sources, leading to an increase in energy costs and power outages when demand peaks.
- eg- As per the study of the Resources for the Future, each 1°C increase in temperature raises energy demand by 0.5% to 5%, depending on the local level of air conditioning penetration.
Challenges that India Needs to Address
- Lagging Behind in Tech Adoption: India’s tech adoption in weather and heat risk monitoring is not comparable to developed countries. They have sophisticated systems, so, more resources, allowing them to deploy more extensive networks and achieve higher-resolution data.
- Less Available Data: Due to more focus on water risk and security, we have more granular data on precipitation, while heat is not a consistent part of the monitoring process.
- Negligence in Enforcement: While more than 20 states have worked with the NDMA to create Heat Action Plans (HAP), most remain on paper. Lack of funding, granularity, and a sustainable vision for transformation hinder their enforcement.
Way Forward
Sustainable Management: It is an urban design and development issue. So we should look at it from a bigger lens of economic policy, city management, and sustainable living in cities.
Heat action plan: There is consensus among experts that city-specific management plans are a far more effective response to heat waves. Building more green buildings is also a key.
Adequate & Required Infrastructure:
- Build Green Roofs: These are an ideal heat island reduction strategy, providing both direct and ambient cooling effects. It also improves air quality by reducing the heat island effect and absorbing pollutants.
- Build Green Infrastructure: By planting trees and other vegetation to reduce the number of greenhouse gases in the region and increase evaporation and transpiration, thus keeping the region cool.
- Light Colours of Buildings: It helps in less absorption of heat by increased albedo and less heat retention.
Technological Advancements: In India, with AI, the development of more advanced modelling techniques for weather forecasts will prepare India for heatwaves and other weather events. For eg, Passive cooling technology.
Innovations: Innovation of running cold water through pipes all across houses and many other architectural-led innovations for heat mitigation.
Building orientation, location, materials to maximise shade, create green spaces, and promote natural ventilation can all help mitigate its effects.
Focus on Individual Health Impact: The aspect of health tech is associated with heat stress. That is the provision of customised heat stress testing and customised alerts and medication based on vulnerabilities to heat or dehydration. This is not based on generalised guidelines but on customised individual data.
Conclusion:
Therefore, considering the above-mentioned impact, it becomes the need of the hour to counter them with apt strategies. Policymakers should focus on reducing unplanned expansion by taking steps to increase opportunities in rural areas and plan for further expansion. Further planning should include passive cooling measures and a proper ventilation setup. So, the increasing global warming needs anthropogenic intervention to make the Earth habitable, but these interventions should be foolproof.