Bangladesh is entering an era where extreme heat is no longer an occasional hardship but an increasingly defining feature of daily life.
Prolonged heatwaves—once confined to specific regions and shorter periods—are now spreading across wider areas, lasting longer and intensifying faster, placing unprecedented pressure on cities, energy systems, public health and livelihoods.
Experts warn that extreme heat is becoming a “new normal,” fundamentally reshaping how people live, work and survive, particularly in densely populated urban centres such as Dhaka.
While global attention once focused on climate threats like floods and cyclones, heatwaves are emerging as one of the most dangerous and least visible climate hazards facing Bangladesh now a days.
The term “new normal” gained prominence during the COVID-19 pandemic, when masks, distancing and remote work rapidly became part of everyday life. Climate experts say Bangladesh is now confronting another transformation—this time driven by climate change.
“For decades, climate change was treated as a distant phenomenon,” said Ainun Nishat, a climate policy expert and former Vice-Chancellor of BRAC University.
“People associated it with melting glaciers or rising seas elsewhere. But now climate change is deeply local. Heatwaves are something people feel directly, and their impacts are immediate.”
Unlike floods or cyclones, heatwaves develop gradually, often going unnoticed until they reach dangerous levels. This slow onset makes them difficult to measure in real time and harder to respond to effectively.
Bangladesh has historically experienced seasonal heatwaves, particularly in northwestern districts such as Rajshahi, Naogaon and Chuadanga. But recent years have marked a significant shift.
According to meteorological data, April 2024 recorded Bangladesh’s longest heatwave on record, lasting for weeks without meaningful relief. Seasonal Nor’wester rains—which typically cool the country—arrived late or failed altogether in several areas.
Meteorologists say the pattern is changing in three critical ways: Duration: Heatwaves are lasting significantly longer than before, Coverage: Heatwaves are spreading across wider geographic areas, Intensity: Peak temperatures are rising steadily.
“Heatwaves are no longer isolated to specific pockets,” said meteorologist Omar Faruq, a senior weather analyst.
“We are seeing simultaneous heat stress across large parts of the country. This signals a structural climate shift rather than seasonal variation.”
During peak summer months, temperatures in many districts regularly rise between 38°C and 43°C, while high humidity makes conditions more dangerous by limiting the body’s ability to cool itself.
Night-time temperatures are also increasing—a phenomenon known as “warm nights.” Without cooler nights, the human body struggles to recover from daytime heat exposure, increasing health risks.
Dhaka’s growing heat trap
Dhaka remains one of Bangladesh’s most vulnerable cities during prolonged heatwaves.
Rapid urbanisation has replaced trees, wetlands and open spaces with concrete infrastructure, significantly reducing natural cooling capacity.
Scientists describe this as the urban heat island effect, where dense infrastructure, asphalt roads and glass-covered buildings absorb and retain heat.
“Dhaka’s expansion has occurred faster than its environmental planning,” said Professor Nazrul Islam, urban planning expert and former chairman of the Centre for Urban Studies.
“When vegetation disappears and concrete dominates, the city becomes a heat reservoir. Heat absorbed during the day is released slowly at night, preventing cooling.”
Urban temperature differences between densely built areas and surrounding rural zones can range from 2°C to 5°C higher, according to environmental researchers.
Key contributors to Dhaka’s heat stress include: Shrinking green spaces, Unregulated high-rise construction, Narrow streets with limited airflow, Increasing traffic emissions, Heat-retaining materials such as asphalt and tin.
Without targeted intervention, experts warn Dhaka may face escalating heat risks that threaten livability and economic productivity.
Rising heat, rising energy pressure
Demand for cooling systems, particularly air conditioners, has surged as temperatures rise across urban households and commercial buildings.
While air conditioning offers temporary relief, experts warn it is also creating a longer-term energy challenge.
Electricity demand peaks sharply during summer, placing enormous strain on Bangladesh’s national grid. Much of the country’s electricity generation still depends on fossil fuels, which emit greenhouse gases and release heat into the environment.
“It’s a feedback loop,” said Dr Md Iqbal Hossain, an energy economist.
“The more we cool indoor spaces using fossil-fuel electricity, the more heat we generate outside. That leads to higher temperatures and even greater cooling demand.”
Bangladesh’s dependence on imported fuel adds further vulnerability, as global supply disruptions can quickly affect domestic electricity availability and costs.
Rising fuel prices also disproportionately affect low-income households.
Heat and inequality
While middle-class households may rely on cooling devices, millions living in informal settlements face extreme heat without protection.
In Dhaka’s slums, homes are often constructed using tin sheets, plastic, and other heat-absorbing materials. Ventilation is limited, and access to electricity remains inconsistent.
Inside these structures, indoor temperatures can rise far above outdoor levels.
“Extreme heat is becoming a silent public health crisis,” said Dr Sabrina Rahman, a public health researcher specializing in climate-health risks.
“In low-income communities, heat exposure leads to dehydration, exhaustion, and increased risk of illness, particularly among children and elderly residents.”
Heat also affects livelihoods. Outdoor workers—rickshaw pullers, day laborers, construction workers, and street vendors—must continue working under intense sun to sustain daily income.
Reduced working hours due to heat stress often mean lower earnings, deepening poverty cycles.
Experts argue that Bangladesh’s urban planning systems have not kept pace with environmental realities.
Unplanned development, lack of zoning regulations, and inadequate environmental oversight have intensified climate risks.
“Heat resilience must be embedded into city planning,” said Engineer ATM Tanbir Ul Hasan, a specialist in climate-resilient infrastructure.
“We need reflective roofs, shaded public spaces, and building materials designed to reduce heat absorption.”
Urban greening—planting trees, preserving wetlands, and expanding parks—is widely considered one of the most effective strategies to reduce heat stress.
Climate researchers emphasize that the increasing frequency of heat waves is not temporary but part of long-term climate transformation.
Roufa Khanum, Deputy Director at the Centre for Climate Change and Environmental Research (C3ER), BRAC University, warned that Bangladesh must shift its response from reactive to preventive planning.
“Heatwaves are no longer isolated events; they are becoming part of Bangladesh’s evolving climate pattern,” Roufa Khanum said.
“What makes this crisis particularly concerning is the cumulative impact—on public health, productivity, water demand, and urban infrastructure. Without proactive planning, the risks will multiply, especially for vulnerable communities who already face limited access to cooling, healthcare, and safe housing.”
She emphasized the importance of localized adaptation strategies.
“Early warning systems, public awareness campaigns, and climate-responsive city planning will be essential to prevent heat from becoming a silent disaster,” she added.
“Investment in heat-resilient urban design and community-level adaptation is not optional anymore—it is a necessity.”
Public health risks intensify
Heatwaves are increasingly linked to rising cases of heat-related illnesses. Hospitals often report increased patient visits during prolonged heat periods.
Common health risks associated with extreme heat include: Dehydration, Fatigue and dizziness, Respiratory stress, Cardiovascular complications, Reduced productivity and concentration.
Health experts warn that vulnerable groups—including children, elderly individuals, pregnant women, and outdoor workers—face the highest risks.
“Public health systems must prepare for recurring heat emergencies,” said Dr Sabrina Rahman.
“Heat action plans—similar to disaster preparedness programs—should become standard practice.”
Water and infrastructure strain
Heatwaves significantly increase water consumption. Urban households require more water for hydration, bathing, and cooling purposes.
However, water availability remains uneven across Dhaka and other cities.
Low-income neighborhoods often face irregular supply, forcing residents to depend on shared water points.
During prolonged heatwaves, water scarcity can escalate into a secondary crisis.
Extreme heat does not only affect health—it affects productivity.
Studies indicate that worker productivity declines significantly when temperatures rise above safe thresholds. Outdoor sectors—construction, agriculture, transportation, and informal labor—are particularly vulnerable.
“Heat stress reduces working hours and increases fatigue,” said Dr M Tamim, energy expert and former government adviser.
“This translates directly into economic losses, especially in sectors dependent on physical labor.”
Industrial production can also slow due to increased cooling requirements and power interruptions.
Renewable energy, particularly solar power, is frequently proposed as a long-term solution to rising cooling demand.
Bangladesh has made progress in solar home systems and rooftop solar installations. However, affordability remains a challenge for low-income households.
Experts stress that large-scale renewable adoption requires: Investment incentives, Infrastructure upgrades, Public-private partnerships, Affordable financing models.
Without these, renewable energy adoption may remain limited to higher-income groups.
Extreme temperatures also affect infrastructure stability.
Road surfaces soften, railway tracks expand, and electricity transformers risk overheating.
Water demand surges, increasing pressure on distribution networks.
“Heat waves test every component of urban infrastructure,” said Engineer Mahmudul Hasan.
“Cities must prepare for long-term heat exposure, not just short-term weather events.”
Experts describe Bangladesh’s current climate trajectory as a convergence of overlapping risks.
These include: Rising temperatures, Urban population growth, Energy dependency, Economic inequality, Environmental degradation
Together, these factors create a complex web of vulnerability.
“The ‘new normal’ is no longer defined by pandemics alone,” said Dr Ainun Nishat.
“It is defined by persistent climate stress that affects every aspect of life.”