Noon – 5 p.m.
The sun is beating down just after 1:30 p.m. as Hussain cruises down a broad boulevard called Africa Marg on his fifth delivery. He passes a crowd forming on the sidewalk. A water deliveryman has fainted and fallen off his motorcycle.
Hussain shakes his head.
For him, surviving the heat is about toughness. “He’s not mentally strong enough for work like this,” he said.
But experts say enduring extreme heat is more a question of what the body can physically bear. Even a young and healthy person such as Hussain can become overwhelmed in an environment like Delhi.
The higher the wet bulb globe temperature, the harder it is for people to keep their bodies cool, because sweat doesn’t evaporate as quickly in high humidity. Dehydration and low blood pressure can make people dizzy and delirious. Their kidneys and hearts must work harder. If their internal temperatures become critically high, toxic substances can leak from their guts into the bloodstream, triggering multiple organ failure, which can be lethal.
Jay, the physiologist, noted that the Australian Open has canceled matches when the wet bulb globe temperature exceeded 32.5C90.5F.
That number, he said, “is the threshold for elite, elite, highly conditioned athletes competing for millions of dollars for playing a sport.” He added: “And these guys [Hussain and Shaw] are supposed to stay in that just to do their jobs.”
During the two days The Post spent with Hussain and Shaw, both men dealt with wet bulb globe temperatures up to 33.8C92.8F.
The extreme conditions of the afternoon coincide with the busiest part of Hussain’s workday — when it becomes most difficult to stay hydrated.
He brings his own water to work each morning, but it usually runs out within a few hours. Hussain is also racing to complete enough deliveries to get a $5 cash bonus, leaving him no time to refill his water bottle.
The easiest way, Hussain says, is to ask his customers for water. But they are often in a hurry, or the request is too awkward.
On this day, an older woman in a luxury apartment won’t even interact with Hussain. She asks him to drop a bag of snacks outside her door before she opens it.
“With someone like her, you can’t ask for water,” he says as he takes the elevator back down.
Across town the next day, Shaw sits on the cool marble floor of the home he’s working on and peers outside through the open facade. The four-bedroom apartments he’s building are worth $1.4 million each.
Delhi is so hot that architects often leave a “sapaat” — or hollow space — that allows hot air to flow out of the building, Shaw explains. But those efforts at cooling are undone by the enormous windows he will help to install.
In this part of ultra-rich Delhi, residents don’t care. “They have air conditioners,” he said.
As a child growing up in rural Bihar, Shaw recalled, he would go cool off in the mango groves whenever it got hot. Delhi offers no such refuge because of a phenomenon known as the urban heat island effect.
The vast paved expanses of cities absorb and then re-emit the sun’s radiation. Heat bouncing off buildings amplifies the feeling of sunlight scorching the skin. Millions of vehicles, factories and air conditioners — most of them powered by fossil fuels — generate “waste heat” that adds to the overall burden.
The problem is almost always worse in low-income areas. A 2019 study found that such neighborhoods in Delhi could be as much as 6C10.8F hotter than a wealthy neighborhood on the same night.
“Heat illness is a disease of vulnerability,” said emergency physician Cecilia Sorenson, director of the Global Consortium on Climate Health and Education at Columbia University. “Those who can protect themselves, do. And those who can’t, don’t.”
Like so much else about climate change, the toll of extreme heat is fundamentally unequal. It’s not just that wealthy people can more readily afford air conditioning, or that they are more likely to live in cooler neighborhoods with lush vegetation, less vehicle traffic and fewer factories. It’s that low-income countries are expected to experience far more dangerous conditions as the planet continues to warm.
In India, where the average citizen produces lower carbon emissions per year than are generated by a round-trip flight from New York to London, the number of extremely hot days is on track to triple in the next 30 years.
“That’s what keeps me up at night,” said Sorenson — imagining the death and devastation of today’s heat waves multiplied by 10, or 30 or 100. “We’re deeply underequipped to deal with what’s going to come.”