When urban cities are the worst sufferers of extreme heat for global warming, Dhaka city has still to address its consequences by tracing extreme heat areas in preparedness to cope with the situation.
From policy to sectoral level, dealing with extreme heats could not be possible in the absence of data on extreme heat island (EHI) and vulnerability of different zones due to temperature variations.
Dhaka city, which has experienced 32 degrees Celsius to 33 degrees in the last three decades, faced more than 38 degrees in April 2024, but it felt more heat than the mercury recorded.
"The concept of extreme heat island is quite visible in urban cities. Dhaka is no exception as the density of population, commercial and industrial activities are very concentrated here than other areas with no proper plan," says Dr Mohammad Rezaul Hasan, head of Climate Change and Environment Unit of the Institute of Water Modelling (IWM).
The EHI concept comes from the phenomenon of captured heat in an area due to concentrated man-made development and vulnerability reaches this high for reasons like global warming, he adds.
Dr Golam Rabbani, head of Climate Bridge Fund Secretariat of BRAC, suggests the government take the urban heat issue seriously as the city's mortality rate increased to 22 per cent from 20 per cent in Dhaka, which is the highest in South Asia.
"The government must declare extreme heat as a disaster so that extreme heat action plan can be chalked out," he told the FE, adding that vulnerability assessment through extreme heat index can guide a proper action plan for all sectors concerned.
Although the government has included extreme heat as one of the components in the National Adaptation Plan, the absence of a heat action plan has made food chain not only vulnerable for humans, but also animals.
According to Dr Hassan, vulnerability at various levels can be identified more after study on the EHI.
The IWM has recently conducted a survey on a single north-south road to start a pilot project on EHI and found 20-22 degrees more temperature were detected on the road surface than that particular day's temperature.
Dr Hasan said such temperature variations could give a guideline to policy-makers and others to take a right decision and proper action to lessen the level of heat.
Sources said health ministry has already directed the stakeholders concerned to provide emergency aid to the hardest-hit people as the number of patients has increased at government hospitals.
Medicine expert Dr Titu Miah of Bangladesh Society of Medicine suggested hosting seminars and symposia to make physicians, particularly in medicine and paediatric departments, aware of the priority treatment for patients.
He, however, said they have now been following the national guideline for physicians to manage the patients like heatwave and dehydration.
Mirza Shawkat Ali, director of the Department of Environment, told the FE that they initiated a study with the IWM to find the deterrent effect on the cities between Dhaka and Mymensingh.
The EHI suggests remodeling urban cities with various features like more green, creating open spaces in a built zone, blue space, north-south facing buildings, less concrete use in buildings, white rooftop or white surface.
The once green Dhaka city's water bodies have now been filled with urban sprawl with little space of green and openness.
Singapore has already taken a multidisciplinary research project styled 'Cooling Singapore' to address urban heat challenges.
smunima@yahoo.com