Bangladesh needs a green transition to survive rising urban heat

Heat stress has emerged as one of the most pressing climate-related challenges facing Bangladesh, particularly in urban areas. Extreme heat events are becoming more frequent and intense, with cities such as Dhaka and Chattogram experiencing higher temperatures, prolonged heat exposure and increasing risks to public health, productivity and liveability.

Heat stress is no longer a seasonal inconvenience. It has become a persistent development challenge intersecting climate policy, urban planning, energy use and socioeconomic wellbeing.

Bangladesh's high population density, rapid urbanisation and unplanned development patterns have significantly increased vulnerability to heat stress, especially in major cities. As urban centres continue to expand and economic activity intensifies, managing rising temperatures will become central to sustaining growth and protecting vulnerable populations.

Urbanisation and the intensification of heat stress

Urban heat stress is closely linked to the Urban Heat Island effect, where built-up areas retain significantly more heat than surrounding rural regions. In Bangladesh, this phenomenon has intensified alongside rapid urban expansion.

Studies suggest that land surface temperatures in some urban areas are up to 3°C higher than nearby regions. Expanding urban infrastructure, declining green spaces and growing population density have all contributed to greater heat retention in major cities.

Bangladesh has also experienced a sharp increase in the number of days exceeding critical heat thresholds. According to World Bank data, the number of days with a daily mean heat index above 35°C nearly tripled between 1990 and 2020.

This trend highlights that extreme heat is no longer an occasional climate event. Instead, it is becoming an increasingly regular feature of Bangladesh's climate system, carrying major implications for public health, labour productivity and urban liveability.

The growing health and economic toll

Heat stress poses serious risks to public health. Rising temperatures increase the likelihood of dehydration, heat exhaustion and cardiovascular and respiratory illnesses. These risks become particularly severe in densely populated urban areas where access to cooling systems and healthcare remains limited.

The economic costs are also substantial.

A World Bank report estimates that heat stress-related physical and mental health impacts led to the loss of around 250 million workdays in 2024, costing Bangladesh approximately $1.78 billion — roughly 0.4% of GDP.

These losses disproportionately affect outdoor workers, daily wage earners and labour-intensive industries.

The ready-made garment (RMG) sector, one of Bangladesh's largest export industries, is especially vulnerable. Research indicates that workers struggle to maintain productivity for more than six hours when temperatures exceed 35°C, leading to reduced output and shorter effective working periods.

Heat exposure inside factories has also been associated with increased absenteeism during summer months.

However, adaptation measures can significantly reduce these losses. Passive cooling interventions such as green roofs and cool roofs can lower indoor temperatures by around 2°C and reduce excessive heat exposure by up to 603 work hours annually.

These findings demonstrate that relatively low-cost interventions can protect both productivity and worker wellbeing.

Emissions, urban growth and rising temperatures

Heat stress is increasingly becoming an everyday reality in Bangladesh, driven by rapid urbanisation and rising greenhouse gas emissions.

Bangladesh's updated Nationally Determined Contributions (NDC3) show that the energy sector accounts for 48.81% of total greenhouse gas emissions, while agriculture contributes 17.04% and industrial processes account for 2.67%.

These sectoral emissions patterns are deeply connected to long-term heat risks.

Research conducted by the Centre for Policy Dialogue (CPD) identifies a strong long-term relationship between agricultural emissions and rising heat stress. Rice cultivation, fertiliser use and livestock management remain major contributors to agricultural emissions.

The study further warns that Bangladesh could experience as many as 140 extremely hot days annually by 2035, with severe implications for public health, economic productivity and urban welfare.

Why fragmented policies will not work

Bangladesh has committed to reducing greenhouse gas emissions by 20.31% from projected business-as-usual levels by 2035 under its third Nationally Determined Contributions framework.

Achieving this target while maintaining economic growth will require coordinated action across multiple sectors, stronger institutional capacity and a clear policy roadmap.

Heat stress cannot be addressed through isolated interventions. It cuts across energy policy, agriculture, transport, public health and urban development.

A cohesive policy framework integrating emissions reduction with climate-resilient urbanisation is therefore essential.

Building a climate-resilient pathway

Reducing agricultural emissions should remain a priority. Climate-smart agricultural practices such as alternate wetting and drying in rice cultivation can reduce emissions while conserving water and maintaining yields.

Improving fertiliser efficiency through soil testing and precision application can also lower emissions without compromising productivity. Better livestock feed management, manure treatment, agroforestry and crop diversification can further strengthen resilience while reducing environmental pressures.

Transport and industrial systems also require urgent reforms.

As urbanisation accelerates, emissions from transport and industry will continue to rise unless corrective measures are adopted. Expanding mass rapid transit systems could reduce reliance on private vehicles and lower urban emissions. Investments in pedestrian-friendly and cycling infrastructure would further support low-emission mobility.

Within industry, improving energy efficiency, upgrading production systems and enforcing stronger emissions monitoring could help support more sustainable industrial growth.

Urban planning must also explicitly incorporate heat mitigation measures.

Urban greening initiatives such as tree planting, green corridors and wetland restoration can reduce surface temperatures while improving air quality. Passive cooling measures including green roofs, reflective roofs and improved ventilation systems can reduce indoor heat exposure and improve worker productivity.

Revising building codes to include heat-sensitive design standards — such as reflective materials, natural ventilation and shaded spaces — will also be critical for long-term urban resilience.

Putting people at the centre

A people-centred adaptation strategy remains equally important.

Public awareness campaigns on heat safety, hydration and workplace rest can help reduce health risks during extreme heat events. City-level heat action plans, early warning systems and temporary cooling centres could provide essential protection for vulnerable populations, including outdoor workers, children and elderly people.

Strengthening data systems — including heat vulnerability mapping and monitoring heat-related illnesses — would also improve policy targeting and response mechanisms.

The urgency of action is growing.

Without timely interventions, heat stress could increasingly undermine Bangladesh's economic productivity, public health and urban quality of life. At the same time, the crisis presents an opportunity to rethink development pathways.

Policies that reduce emissions, expand urban green infrastructure and strengthen climate resilience can generate long-term benefits for both people and the economy.

The decisions made today will determine how resilient, productive and liveable Bangladesh's cities remain in an increasingly warmer future.

Foqoruddin Al Kabir is a senior research associate at the Centre for Policy Dialogue (CPD). He can be reached at kabir@cpd.org.bd. Md Takrim Hossain is a research associat at the Centre for Policy Dialogue (CPD). He can be reached at takrim@cpd.org.bd

Disclaimer: The views and opinions expressed in this article are those of the author and do not necessarily reflect the opinions and views of The Business Standard.