@D_J_Nathanson When you're talking about private jets, I totally agree.

But when you split up the climate costs of a commercial jet between all its passengers, and compare that to the carbon produced by enough cars to carry them on the same route, I think the ratio flips.

@LouisIngenthron That's not what the data say. I encourage you to examine the data. The difference between private and commercial is discussed in both links that I posted.

@D_J_Nathanson Quote from the first article: "Per passenger, a flight from Auckland to Wellington will put a similar amount of carbon dioxide into the air as driving solo in your car."

The second article doesn't seem to have anything comparing aircraft vs cars, but it does have graphs showing that passenger air traffic has grown by roughly 6% every year, and yet the GHG emission from fuel was *less* in 2016 than it was in 1990.

Finally, check out this United States Department of Energy graph showing that airlines are more fuel-efficient than any non-rail ground travel option: https://afdc.energy.gov/data/10311

@LouisIngenthron As to the first, I think you're cherry-picking instead of engaging with the thrust of the article. The next paragraph discusses the additional effects "the net result when these processes are added together is to drive more warming."

In addition, it is not just how the amount of emissions but where they are emitted. High altitude emissions are worse.

In addition it is not just the fuel, but the contrails which drive warming.

@D_J_Nathanson Your first point is directly contradicted by the article you cited: "it doesn’t matter much whether you release it from the exhaust pipe of your car at sea level or from a jet engine several kilometres high"

As for your second point, the science linking contrails and climate change is shaky at best, as even the article you cited mentioned:
"The science is not as clear cut on how contrails influence the climate"

There's evidence that they reflect light to cool the climate as well, and that's not in the simulations.
Moreover, only like 10% of flights even create contrails. You have to be very high up in very cold and wet conditions, otherwise they just won't form, or they'll dissipate almost immediately.
And even that will be less of a concern as more efficient fuels are created that produce less soot and therefore fewer particles to seed cloud formation... so contrails may, one day soon, be a thing of the past.

@LouisIngenthron I’m happy to engage further in the future but I need to prep for a hearing.