It turns out that planes — like humans and icebergs — don’t do well in heat.

And as climate change lifts temperatures around the world, it could mean fewer flights taking off, fewer people boarding flights, and more expensive tickets, according to a new paper from Columbia University and Logistics Management Institute, a consulting firm.

The paper predicts that by the middle of the century, as many as 30% of flights will have to be delayed during the hottest parts of the day.

That’s because in hot weather, planes struggle to lift off the ground and stay aerial.

In June, more than 40 flights were grounded in Phoenix during a stretch of time when temperatures soared above 120 degrees Fahrenheit.

This kind of mass-grounding could become the norm. The researchers argue that LaGuardia in New York, because of a short runway, and Dubai’s airport, because of exorbitant heat, will be among the worst-affected.  

Airlines can adapt to the hot weather in a few ways, though. They can lower passenger and cargo limits to make planes lighter, lengthen runways to give planes more speed, and improve engine power. All of these costs, though, will be passed onto the consumer, according to the study.

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Climate change could disrupt air travel in other ways, as well.  

Increased air turbulence could makes flights riskier, changing jet streams could increase flight times, and rising sea levels could flood airports, preventing flights from even taking off, the report predicts.

“We tend to ignore the atmosphere and just think that the plane is flying through empty space, but of course, it’s not,” Paul D. Williams, a professor in the Department of Meteorology at the University of Reading in Britain, told The New York Times. “Airplanes do not fly through a vacuum. The atmosphere is being modified by climate change.”

Transporting roughly 3.5 billion passengers annually, the global airline industry is a major source of carbon emissions and the constraints posed by climate change could, in a roundabout way, cause companies to reduce their environmental footprints.

After all, the worse climate change gets, the harder it will be for planes to fly, so there are clear incentives for tackling the problem.

The airline industry is beginning to prepare for tougher conditions.

On Earth Day, an industry group put out this statement: “Each aspect of your flight – whether as a passenger or a recipient of a package shipped as air cargo – is handled with environmental care.”

Ultimately, this is a new field for scientists, and they’re still figuring out how to measure all the potential variables that could affect flight.  But air travel won’t be the only form of getting from point A to point B that will be affected by climate change.

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Walking, running, bicycling, and other types of physical activity will become more challenging as temperatures rise.

Traveling by plane is in many ways a “first-world problem.” Using the human body to get around is anything but.