As an unprecedented heatwave sweeps South Asia, there are few hotter topics. Over the past week, with vast swathes of India and its neighbourhood experiencing a dangerous rise in temperature, often combined with humidity, there has been an information explosion.
However, what is not adequately stressed in the public conversation is that while heat waves affect everyone, they do not affect everyone equally. And heatwave preparedness needs to pay a lot more attention to the different impacts on different groups of people.
Clearly, heat is not just another four-letter word. Not only does climate change-fuelled extreme heat affect the human body and health, its impact is also felt across the intertwined web of geopolitics and geoeconomics.
In March, an unusually scorching sun affected part of the crop in the major wheat-producing states of Haryana, Punjab and Uttar Pradesh, triggering concerns about its impact not only within the country but also beyond. The wheat fields shrivelling up in premature heat in parts of northern India coincided with Russia's invasion of Ukraine and strained global staple food supplies. Russia and Ukraine together export more than a quarter of the world's wheat.
We already know a lot about this because it is being discussed as the blistering heatwave continues. As I write, the maximum temperature in Delhi, where I live, has crossed 43.5 degrees, the highest in April in 12 years. Agra sizzled at over 46 degrees. Scientists in India and across the world forecast that worse will be in store as climate change gathers pace. While Indian policymakers need to take into account differential impacts on different socio-economic groups, the overall situation is going to rapidly get worse unless industrialised countries control climate change by reining in their greenhouse gas emissions.
And tracking temperatures alone is not useful for understanding high-risk areas or in identifying groups at high risk, as many public health experts are pointing out.
What we need is a 'heat vulnerability index' which factors in landscape, demography and socio-economic factors, says Dr Soumyadeep Bhaumik, a public health expert working with The George Institute for Global Health.
The reason is obvious. While many of us can protect ourselves from extreme heat by working from air-conditioned homes and offices, millions of heatwave-impacted people do not have that luxury.
On a recent afternoon, when the temperature had already crossed 42 degrees, I found migrant workers from Cooch Behar working at a construction site near my house in South Delhi. There had been no change of timings nor any flexibilities on the site, a woman loader told me. The Rs 350 that the woman gets at the end of the day sustains her. Daily wagers like her who are forced to work outdoors in debilitating heat suffer from cumulative heat exposure because they also live in overcrowded spaces with little ventilation and frequent power outages.
This is the face of India's informal economy which sustains most people in this country. And a host of studies are telling us that the situation is likely to worsen in the coming years. Heat stress is projected to reduce total working hours worldwide by 2.2 per cent and global GDP by US$2,400 billion in 2030, according to a 2019 study by the International Labour Organisation (ILO) titled 'Working on a warmer planet – The impact of heat stress on labour productivity and decent work'.
What should be of interest to India is that countries and regions with precarious labour market conditions are likely to suffer higher productivity losses with such extreme heatwaves.
Within the Asia and Pacific region, countries in Southern Asia are the most affected by heat stress, and within Southern Asia, the country most affected by heat stress is India, which lost 4.3 per cent of working hours in 1995 and is projected to lose 5.8 per cent of working hours in 2030.
India is, in absolute terms, expected to lose the equivalent of 34 million full-time jobs in 2030 as a result of heat stress. Although most of the impact in India will be felt in the agricultural sector, the ILO report points out, "more and more working hours are expected to be lost in the construction sector, where heat stress affects both male and female workers."
As an example, the ILO study points to occupational heat stress among brickmaking workers in India. "The Indian brickmaking industry employs millions of people, most of whom have migrated from poor villages to the outskirts of cities. These workers, including many young children, often have low socio-economic status, work under harsh conditions, and receive low wages or even none at all. The severe risks faced by such workers include high temperature and radiant heat levels, a heavy physical workload, and also a lack of awareness of occupational safety and health-related issues," it notes.
This heat exposure is exacerbated by limited or non-existent on-site cooling options. "The majority of the workers were aware of their heat stress symptoms, but they lacked the knowledge and resources to implement preventive measures," the study says. The statutory instruments that do exist have not been successful in protecting these workers.
A study by McKinsey Global Institute has also flagged the prospect of India experiencing more heatwaves by the 2030s that could make construction and other outdoor work lethal. India's economy is highly dependent on heat-exposed labour, it points out.
A vulnerability assessment study by the Indian Institute of Public Health, Bhubaneswar (IIPHB) that looked into the effects of heat stress on the health and productivity of high-risk populations in the Odisha capital found that compared to residents of non-slum areas, "slum residents are more at risk of getting exposure to heat because of the housing structures, heat-trapping materials on (the) roof (asbestos and tin), overcrowding, lack of electric supply, and access to water supply and exposure to additional heat during cooking because of use of chullah."
Heat action plans (HAP) must pay more attention to these highly vulnerable populations as temperatures soar across the country.
Ahmedabad was the first Indian city which developed a heat action plan after more than 1,300 recorded deaths following a heatwave in May 2010.
The Ahmedabad model hinges on early-warning systems, colour-coded alerts, community outreach programmes, and reduced timings for schools and factories.
Many Indian cities have followed, but the effectiveness of HAPs varies.
"There must be convergence between various ministries and departments," says Vikas Desai, a former professor of community medicine and currently Honorary Technical Director Urban Health and Climate Resilience Center of Excellence (UHCRCE) Surat. "This is not just the problem of the health department. Every department needs to pitch in, and you need local planning and local capacity building. Every city needs a HAP, and a HAP is not static. Every year, it needs to be reviewed. Local authorities also should involve academics who have been working in this area to develop more climate practitioners. This will help build capacity."
Like many other public health experts, Desai also stresses the need to go beyond temperature and factor in social determinants. "Exposure to extreme heat is worsened in overcrowded settings and where there is poor ventilation. We need to factor in air mobility, overcrowding, cumulative exposure."
The differential impacts of a heatwave mean solutions cannot be uniform. "There is no point asking everyone to drink lemon juice to beat extreme heat. With the price of lemons being what they are, it is out of reach for the poor," says Desai. "But what can be done is to have long-term plans which involve the community to prepare beverages that can be used during scorching summers. The involvement of the community is critical in every solution. Right now, there is an absolute need to ensure availability of adequate clean water everywhere, including schools and hospitals."
Disturbingly, it is not easy to get hard data on the nationwide impact of heatwaves on multiple fronts on different segments of the population. A lot of the information is scattered.
There is an urgent need for these 'isolated pieces' to come together, as Dr Shweta Khandelwal of the Public Health Foundation of India (PHFI) notes. Khandelwal says there should be a joint committee bringing together key players from diverse sectors.
It is evident that long-lasting spells of heatwaves are not a problem in the future. They are already happening and impacting different groups in different ways.
Which brings one to the urgent need of the hour –– a comprehensive, country-wide assessment of heat vulnerability and hyper-local heat action plans that focus on India's stark realities and that can adapt according to the evolving situation.
(Patralekha Chatterjee is an independent journalist and columnist)
Disclaimer: The views expressed above are the author's own. They do not necessarily reflect the views of DH.
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