Enlarge / So many airplanes are in line on the runway waiting for take off. These Air Force planes are part of Operation stop service to transport in Covid-19 situation. (credit: Naruecha Jenthaisong | Getty Images)

Fastening the seat belt buckle and knowing your flight is on its way to its destination: Nice. Getting stuck in a tarmac traffic jam and waiting for your flight to take off: Not so nice. Turns out the wait is also not nice for the planet.

Flying in an airplane is already one of the most emissions-intensive things you can do. Globally, aviation produced over 1 billion tons of carbon emissions in 2019 , more than 2 percent of all human-generated emissions—more than either shipping or rail. Aircraft engines also emit nitrogen oxides, soot particles, and water vapor, which also contribute to warming the planet.