Gig workers often remain on the job when the rest of us escape extreme weather, with some potentially significant repercussions for their long-term health, as well as their employers’ bottom line.

That’s according to a new paper from Susan Feng Lu, a professor of operations management and statistics at the Rotman School of Management.

It found that food delivery workers are more likely to hit the streets in more challenging weather conditions — especially during the lunch hour, the hottest time of day — due to surging demand.

However, they often don’t earn the pay premium they expect for doing so, and those relatively minimal earnings increases are often offset by long-term health repercussions — especially among a workforce that often lacks access to healthcare coverage.

Gig work, particularly delivery, is a growing industry. According to the World Bank there are as many as 435 million online gig workers globally. There were also 870,000 full-time gig workers in Canada in 2022, according to Statistics Canada, and 1.5 million had done at least some gig work in the previous 12 months, including 245,000 delivery workers.

And these workers are increasingly operating in extreme temperatures. According to a 2024 study by Climate Central, there were 41 extra days of extreme heat last year due to climate change, and the Government of Canada warns that the country is warming at twice the pace of global averages. 

The risks to gig workers are particularly high for those who deliver by foot, scooter or bike rather than from a car, as well as those operating in countries without public insurance or formal regulatory protections.

Lu says she was inspired to study the effects of extreme weather on gig workers after spending a summer in China. There she noticed that when the temperature rose, the streets emptied of pedestrians and filled with food delivery workers.

Lu and her co-researchers analyzed a dataset provided by a food delivery platform in China, homing in on two cities where the platform held dominant market power to ensure a comprehensive view of its operations in those locations.

The analysis included more than 580,000 orders delivered by 1,272 workers and found that order volumes rose along with the temperature. For every 5°C increase on the thermostat, there was a 9.6 per cent increase in orders per hour.

Food couriers worked six per cent longer during heat waves, when the temperature is considered “dangerous” or “extremely dangerous” for outdoor activities, according to the U.S. National Weather Service’s Heat Index, the research shows.

“In extreme weather the number of orders increased and the expenditure per order also increased,” says Lu. “Gig workers are willing to work more in extreme weather because they think they will earn more money, but it turns out, [the hourly pay premium] is no more than the cost of a bottle of water at the supermarket.”

At the same time, Lu says working in those extreme conditions can come with significant long-term cost. 

“Sadly, when I talk to [the delivery workers], none of them notice how the hot weather will affect their health,” she says. “According to the U.S. Department of Labor heat hazards can cause death and injury, but it’s also difficult to document the causality; many people suffer a heart attack without realizing it’s caused by behaviours like working in extreme weather.”

Extreme weather doesn’t just pose a challenge to the gig workers managing it on the ground, but also their employers, whose services see greater demand in extreme weather but become less reliable when they fail to take those conditions into consideration, says Lu.

“This means more delays, more unhappy consumers, and it hurts the reputation for the platform in the long run,” she says, adding the reputational liability could also weigh on investors. “There’s lots of corporate finance literature that shows companies that operate more responsibly are viewed more highly by investors, which can help them perform well on the stock market.”

Food delivery platforms, however, do have some options for addressing the increased demand on their services — and their couriers — in extreme conditions.

“These algorithms need to take the weather into consideration, and during those extreme weather days, they should increase the fees,” she says. “When fees increase it reduces demand, so the platforms become more reliable, and gig workers still earn more money.”

Governments can help reduce the effects of extreme weather on food couriers by mandating more protections for gig economy workers, such as mandatory sick leave and healthcare benefits.

“The local governments can also ask companies to subsidize gig workers in extreme weather, either by requiring them to pay extra, or offer protections, like requiring they provide water, fans, sunscreen and set up shelters where gig workers can stay during hot weather,” Lu says.

Customers, too, can better protect the gig economy workforce by pooling their orders, tipping extra, demonstrating a little extra patience, or simply packing a lunch during extreme weather events.

“Those gig workers are trapped by algorithms, and now they’re also trapped by extreme weather,” Lu says. “I hope that through my research the public will better appreciate their sacrifice.”

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