The reality of living with extreme heat in India

[AUDIO LOGO] FLORA LICHTMAN: Hey, it’s Flora, and you’re listening to Science Friday.

India is one of the most climate vulnerable countries in the world, and weather disasters like heat waves have become more extreme and more common in recent years. At one point this year, the 50 hottest cities on the planet were all in India. The average peak temperature in those cities was 112 degrees Fahrenheit.

So how is this extreme heat affecting people in India, and what needs to change to keep people safe? My next guest has some answers. Dr. Gulrez Azhar is a physician and researcher who has spent much of his career studying the health impacts of heat waves in India. Gulrez, welcome to Science Friday.

GULREZ AZHAR: Thank you so much.

FLORA LICHTMAN: I want to hear a little bit about how you got into this field. Would you tell me a little bit about how you grew up?

GULREZ AZHAR: I grew up in a state called Uttar Pradesh, which is the largest state by population in the country. It’s in the northern part of the country. It’s among the– I think the second poorest state in the country per capita income, somewhere around $1,000 per person per year.

Then went to did my med school and residency training in community medicine, which meant I was working out and was exposed to far more of the rural life or the urban slum communities or mobile health clinics in hard-to-reach areas. So that was my exposure both as someone who was born there, grew up there and then my medical residency training in that state.

FLORA LICHTMAN: And why did heat capture your attention?

GULREZ AZHAR: After my residency training, I went to study public health in Europe. And, of course, it’s a contrast, huge contrast, from the hinterland of India. And there are things I noticed that, for example, European households didn’t have air conditioning, they didn’t have really fans, and there was this historical discussion about the heat wave in Europe, which has happened before and it had apparently killed 70,000 people there. I think it was 2003.

And coming back to India, I was posted in another state, the western part of the country, and that state was hot and hotter than the state I grew up in. I asked about the winter season when it’s going to come, and they said there are only two seasons here. It’s either hot, or it’s very, very hot. And so you are in the hot season, which meant the winter season.

FLORA LICHTMAN: Mild, relative to the very, very hot season.

GULREZ AZHAR: And you start to think that if compared to Europe, which was cold, if this winter was so unsufferable and comfortable, then what was going on in summer? And if in Europe mild Europe it had 70,000 documented deaths in places which are less densely populated, wealthier, have better health care systems, and are not as hot, so then what’s going on in India. So we went and looked into the data, which we have, and admittedly data in other parts of the world are not very accurate or complete but we still had orders of magnitude, I think 1,300 excess deaths in that month and I think more than 300 excess deaths per day.

FLORA LICHTMAN: And this is just one city.

GULREZ AZHAR: Just one city. Just one-, two-, three-day heatwave period. So that was completely eye opening. And before that, there was this assumption that people are somehow used to it, and India is always hot. It is true to some degree, but at the same time, there are certain limits to human adaptation, human physiological thresholds. There are those hard limits which we as humans just cannot.

And we notice that temperatures, even right now and in future are projected to exceed those human survival thresholds. So what would happen to places, and it’s already to some degree gradually happening. And we are seeing that especially people who are working in service-based industries. Even agriculture, construction laborers, people who are forced to spend time outside, don’t have access to air conditioning and that’s huge. Access to air conditioning in India is in single digits all over the country. So more than–

FLORA LICHTMAN: Single digits?

GULREZ AZHAR: Single digits. More than 94% people do not have access to an air conditioner at home. Many people don’t even have a power connection at home. Many have power connections.

FLORA LICHTMAN: Wow. More than 94% of people don’t have air conditioning.

GULREZ AZHAR: Yes.

FLORA LICHTMAN: In India.

GULREZ AZHAR: Yes. That’s the number. Yes. And imagine look at the sheer scale of people. The population we’re talking about is 1.5 billion people. And what do you think would happen if 1.5 billion people somehow magically had access to air conditioning and they all switched it on. Think of what would happen to the power grid and noting that most power India comes from fossil fuel, so not what’s going to happen to the world at large with the emissions, which would come from everyone switching on air conditioning. So it’s an impossible situation to be in.

FLORA LICHTMAN: What are the challenges with accounting for actually the effect of heat in India? Do we have good numbers?

GULREZ AZHAR: Not really. There are two challenges here. First, the broader challenge is itself how health data is collected, which is incomplete as against, for example, Scandinavian countries or in the US where you have registries. You have all the data from birth ’til death linked to a central ID.

In India, not so much. So, for example, in the city I was working in Ahmedabad, it’s in the state of Gujarat, you have a lot of people coming from neighboring states and far off states from the country to work as construction or construction sites on other kinds of jobs. And those people are from different states. They speak a different language. They don’t have local ID cards. So those people who unfortunately die in heat in those parts.

Their deaths are less likely, very less likely to be registered or put into a system. They’re being issued a death certificate. So those deaths are just not in the system. So that’s the one systemic issue about death in general, death or any health reporting in general.

And secondly not all deaths, which happen during heatwave event are heatwave deaths. So the cause of death on the death certificate, which should be a heat stroke or a sunstroke, it’s a very small fraction of the total number of excess deaths you would see during that event.

FLORA LICHTMAN: ‘Cause people have comorbidities.

GULREZ AZHAR: Exactly.

FLORA LICHTMAN: And, yeah, they have other illnesses, and they flare up. And so the cause of death is something else even if it was triggered by the heat wave.

GULREZ AZHAR: Absolutely. So the cause of death would be cardiorespiratory arrest, renal failure, or something. But the renal failure is because of dehydration or cardiorespiratory arrest in the elderly is because they just can’t live through that blistering 140-, 130-degree Fahrenheit summer afternoon.

FLORA LICHTMAN: If you don’t have good numbers, can you have accountability? Is that step one?

GULREZ AZHAR: Yes. Having good numbers, of course, is essential and critical. At the same time, we try to make do with what we have. So, for example, it could be ambulance calls. It could be certain conditions, which are more likely to show up in summers and heat and account for that. So, yeah, there are ways around that. We could use novel methods like phone apps, that kind of stuff.

FLORA LICHTMAN: It’s not impossible.

GULREZ AZHAR: It’s not impossible.

FLORA LICHTMAN: It’s just hasn’t been done.

GULREZ AZHAR: Humans are innovative and humans are resilient. That’s one thing I’ve learned. This is a really sad topic to do research on, but you can never underestimate human ingenuity or human resilience both.

FLORA LICHTMAN: I want to hear about that in a little bit, but first I want to talk about your work in Ahmedabad, the city in Western India. Tell me about some of your research there.

GULREZ AZHAR: In our study we published, we had a research on construction sites looking at how workers are exposed. And so we noticed that in construction sites, 10% of our construction– the worker population being hospitalized from dehydration or heat exposure.

FLORA LICHTMAN: 10%?

GULREZ AZHAR: 10%, yeah. So, again, so that also gave us a sense of exposure and also a sense of what we could do about it. So we conducted these training sessions with the municipal corporation working in partnership with them based on that. Whatever they suggested, they mentioned, oh, we could keep the parks open in the day. We could make sure that unscheduled power cuts don’t happen or repairs don’t happen in the afternoon when it’s really hot.

We supply water by tankers once every week. We could probably do it once or twice a week to the slum communities. Then gradually the health department said they could prepare their own people to be– to train them on how to treat heat stroke, heat illnesses. Make sure water supplies in place. Ambulance service would train health technicians. Availability, ice packs available, cold water, all of that.

So that gradually took on. And then I think this work has now scaled up, and it’s being implemented in many, many cities in the country, several dozens, probably more. So, yeah.

FLORA LICHTMAN: Is there a myth or a misunderstanding about extreme heat that you want to myth bust?

GULREZ AZHAR: There is this assumption that in those parts of the world, it’s the men who go out and work and the women stay indoors. And so therefore it’s the men who are affected by heat, and the women somehow are not, which is absolutely not true.

So what happens is a quarter of households in the city, Ahmedabad, a quarter of it is a slum community, which means that by definition it doesn’t have– those households don’t have an indoor toilet. They wouldn’t have indoor water supply. So then women wouldn’t drink a lot of water because then they need to relieve themselves, and there is no indoor toilet. They cannot go out in the open in front of men in groups, so they would dehydrate themselves. They wouldn’t have an indoor kitchen.

The source of cooking food is cow dung cakes and wood shavings. So wood shavings makes it smoky inside. It’s a slum house. It doesn’t have multiple windows, fresh air circulation. The roof is corrugated tin sheet, which heats up like an oven. So it’s smoky hot inside, and that’s why when we counted deaths, we had more women deaths than men in Ahmedabad.

So it’s a combination of all of these things which layered on top of each other, which just makes it incredibly, incredibly– it’s something which has to be felt. It’s really hard to explain to someone, oh, it’s hot.

As someone who grew up– I studied in an English medium school. We would talk about these poetry and warm summer day English poetry, I think Shelley or Keats, and I always wondered what is so good about a hot, warm summer day. To me, it is not something to be happy about, something to be really terrified of. So, yeah.

FLORA LICHTMAN: You mentioned earlier that working in this area has taught you that people are ingenious and resilient. Will you speak a little bit more about that?

GULREZ AZHAR: Absolutely. So from historically ’til present, for example, yes, it’s hot, and it’s going to get hot. It’s getting hot every year. People tell me, oh my God, this is the hottest year of my life. And I’m– and I’ve– I’m not that person, but I think in my heart that this is actually the coldest summer of the rest of your life. Next year is going to be hotter than that.

FLORA LICHTMAN: Is that glass half full or glass half empty? I’m not sure.

GULREZ AZHAR: Exactly. Every year it’s going to be hotter than that. That being said, my dad was the first person in our since historical family who used air conditioning. My grandfather was the first person who actually ever saw a fan or a power connection. But in those parts of the world, still very hot in the past.

They had been densely populated, and they’ve been doing economically all right. So that was the part that gives me hope. Although solutions don’t have to be really glamorous or expensive. Many of those solutions are really simple, common sense.

The thing I talked about, people just being aware of it, similarly, historically, just changing your work timings. Working at home, trying to take a nap in the afternoon somehow, drinking plenty of water, the kind of clothes you wear, the kind of food you eat, the kind of homes you build, designs, all of them would add up– would add certain degrees of protection from heat. Some recent– some positive findings in those studies were that people who were aware that heat could be a threat. If you just directly ask them, do you think heat is something you should be concerned about and they would say yes. If those people who recognize heat could be some kind of a threat are four times less likely to actually suffer from any heat-related illness versus those who don’t see heat as a threat, who see heat as something, just a part of being– existing in those parts of the world.

FLORA LICHTMAN: There’s been so much coverage of heat waves this year. Right now, we’re hearing a lot about Europe. How are you thinking about this moment?

GULREZ AZHAR: This is hard. Often it scares me that think of not so much in Europe and North America but think of countries which are pretty hot– Gulf countries, Arab countries, densely populated parts of the world, especially urban areas where the maximum temperature routinely crosses 45, 50 degrees centigrade. So looking at the urban heat island effect, looking at other factors and humidity and heat indices, those temperatures do exceed human survival thresholds.

So what scares me is I keep thinking are these societies and cities literally just a few hours of power failure away from a mass casualty event. And that scares me. So power cut, no air conditioning, people not adapted to those temperatures don’t know that behavioral old lifestyle things which societies were doing in the past, it’s just scary.

FLORA LICHTMAN: It is really scary. How do you keep yourself from not getting a sort of overwhelmed by this information? What keeps you working on it I guess?

GULREZ AZHAR: I think I look at it as a broader problem, broader puzzle, and trying to find solutions, small pieces of that puzzle. So for preventing heat in communities, a small part of the puzzle is that heat action heat preparedness plan. Similarly you’re looking at community and national level solutions to prevent heat, so now we’re talking about emission regulations, stopping further warming, planting more trees, all of that. Otherwise, this is just so overwhelming and scary, and the worst part is we still at this day and age have people who actually say none of this is– just how?

FLORA LICHTMAN: Dr. Gulrez Azhar is a physician and researcher who studied the health impacts of heat waves in India. Gulrez, thank you for joining me today.

GULREZ AZHAR: Absolutely. Thank you.

[MUSIC PLAYING]

FLORA LICHTMAN: This episode was produced by Rasha Aridi Thank you for listening. I’m Flora Lichtman.

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