Comparing greenhouse gas emissions Essentially, one long flight releases the equivalent of nearly 14 percent of the annual emissions from your car. The same route, when driven, will result in the release of 1.26 tons of carbon emissions.

Per passenger mile, planes are generally significantly worse for the environment than cars, particularly due to high-altitude emissions. While a modern fuel-efficient car might emit roughly 150-200 grams of CO2 per mile, a commercial jet emits about 250-300 grams per passenger mile. However, the true environmental impact of aviation is nearly double that of cars when you factor in "radiative forcing." When planes burn fuel at 35,000 feet, they release nitrogen oxides, water vapor (contrails), and soot into the upper atmosphere, which trap heat much more effectively than ground-level emissions. In 2026, while electric cars are becoming the norm, aviation remains heavily reliant on fossil fuels. A single long-haul flight from London to New York can generate as much CO2 as an average driver produces in an entire year. However, if a car is carrying four passengers, its per-person footprint is much lower than a plane; but if a person is driving alone in a large SUV, the "gap" between the car and the plane narrows significantly, though the plane's high-altitude effects still make it the more "carbon-intensive" choice.