By Shreedhar Joshi, Alumnus of MIT World Peace University, Pune, Maharashtra, India

The cities of the Bay of Bengal Initiative for Multi-Sectoral Technical and Economic Cooperation (BIMSTEC) region spanning South and Southeast Asia, are confronting a unique rise in temperatures, driven by both local urbanisation trends and the global climate crisis. Recent years have seen major heatwaves sweep across cities like Delhi, Dhaka, Yangon, and Bangkok, with surface temperatures often exceeding 45°C[1]. These extreme weather events are not anomalies but increasingly recurring patterns, intensified by global warming and the urban heat island effect, wherein densely built urban environments trap and retain heat. The consequences have been severe, for e.g. increased mortality due to heat strokes, higher incidence of respiratory and cardiovascular diseases, disrupted energy systems due to excessive demand for cooling, and lost economic productivity, especially among outdoor workers and the urban poor. According to the World Bank, by 2050, South Asian countries could lose up to 5% of GDP annually due to heat stress alone. These figures highlight that cooling cities is not merely an environmental imperative; it is a socio-economic necessity.

Natural and sustainable cooling solutions must become central to the planning and management of urban areas across the BIMSTEC region. Cities need to shift away from energy-intensive, artificial cooling systems and move toward nature-based interventions that offer co-benefits for health, biodiversity, and climate adaptation. Increasing urban green cover through the planting of indigenous trees, developing city forests, and restoring degraded urban wetlands can help reduce surface temperatures by 2 to 5 degrees Celsius.[2] Encouraging the adoption of green roofs, vertical gardens, and permeable surfaces for rainwater absorption not only provides thermal regulation but also improves air quality and urban aesthetics. Water bodies, such as lakes, ponds, and canals, must be revitalised and integrated into urban planning, as they play a crucial role in evaporative cooling. Furthermore, urban planning should include shaded walkways, breathable open spaces, and community gardens that allow residents to cope with heat in a more sustainable and equitable way. These measures align strongly with the environmental goals of BIMSTEC, especially under its priority areas of climate change, environment, and sustainable urban development.

As a regional bloc sharing common environmental vulnerabilities and developmental aspirations, BIMSTEC must adopt a unified and actionable agenda to address urban heat. First, there should be a collective push to establish a BIMSTEC-wide Urban Heat Resilience Framework. This would include heat vulnerability mapping using real-time meteorological data shared by agencies like the India Meteorological Department and other national weather bodies. Second, BIMSTEC should facilitate the harmonisation of urban planning policies by encouraging member states to insert minimum green space thresholds and heat-resilient building norms in their local regulations. Third, a dedicated Climate Adaptation Fund under BIMSTEC should be proposed to support cities financially in implementing green infrastructure projects. This could be developed in collaboration with multilateral climate finance mechanisms such as the Green Climate Fund. Fourth, BIMSTEC should promote cross-border knowledge exchange and capacity building. Cities like Ahmedabad, which have successfully implemented heat action plans, can provide a model for others in the region.[3] Additionally, universities and research institutions across member countries should be encouraged to jointly study and develop context-specific cooling innovations, such as using traditional architectural styles that naturally reduce heat absorption.

Looking ahead, the way forward for BIMSTEC lies in treating urban cooling as a core regional development priority, not just an environmental add-on. As cities continue to grow, their role in mitigating the climate crisis also increases. By adopting a low-carbon, nature-centric approach to urban resilience, BIMSTEC can lead by example in the Global South. Collaborative governance, sustained political commitment, and people-centric urban policies will be key to ensuring that the region’s cities remain liveable, inclusive, and climate-resilient in an increasingly warming world. In tackling the challenge of rising urban temperatures, BIMSTEC has the opportunity to not only safeguard its cities but also redefine sustainable urbanisation for the future.

[1] India Meteorological Department (IMD). (2024). Annual Climate Summary 2024.

[2] U.S. Environmental Protection Agency (EPA). (2023). Using Trees and Vegetation to Reduce Heat Islands.

[3] Natural Resources Defense Council (NRDC) India. (2020). Ahmedabad Heat Action Plan: Protecting Health and Reducing Risks from Extreme Heat.

Disclaimer: The views expressed in this piece are those of the author/s and do not necessarily reflect the views or policies of AIDMI.