Please note that all coherent carbon neutrality scenarios use tree planting for carbon offsetting PLUS a reduction in plane travel. There are more essential services that will require carbon sinks to function at full regime.

Air travel is easily replaceable by low-carbon alternatives that exist today. When you do the accounting of carbon offsetting/carbon sinks capacity, it becomes quite obvious everything unnecessary must go.

Of course, I don't disagree with the reduction. But an economically efficient reduction will reduce from people who can't afford to pay the premium and leave people like me to spend appropriately. This is possible precisely because it is unnecessary. If air travel were necessary then we'd have to ration it by person. Since it is not, we can afford to ration it by the dollar.

That it's not an immediate live or die situation does not mean that lives of many people won't be significantly worse. I generally dislike the argument because I care about Earth and the life on it, but it would be really interesting to see how bad would increased temperature be in terms of dollars.

> Air travel is easily replaceable by low-carbon alternatives that exist today.

Intercontinental and cross continental travel are a bit harder to replace with low carbon alternatives.

Europe has a functional high speed rail system due to its high population density, but the distances between some city pairs in the are hard to replace with rail or other low carbon alternatives. Think of Los Angeles to NYC, or San Francisco to Paris.

Many of these flights could be replaced by video conferencing, but if one really has to travel that distance, rail is a hard sell. It's not unpleasant to take Amtrak across the continent, but it's not fast either.

1) A high-speed rail from LA to NYC would take ~15h with stops in the middle. While it's a large investment, it would shave off millions of tons of CO2 released every year. Of course, you cannot travel oceans with high-speed rail.

2) Again, fast travel across the globe is a luxury, not a necessity. More than 80% of the world's population has never been near an airplane.

A large investment is quite an understatement. At say, ten million USD per kilometre (a low estimate compared to actual costs borne by France for building the TGV [0]), and a bird's eye distance of 3966 kilometres between LA and NYC [1], that's almost 400 billion dollars, or about 60% of the non-defense discretionary budget of the US for a single year. Keep in mind that's a very generous cost per kilometre; California's HSR projected costs are north of 60 million USD per kilometre.

And that's for a single pair of cities, with no cost overruns, no tunnels, straight line distance. It also excludes things like stations, rolling stock, and maintenance.

It's not impossible to build, but having high speed rail throughout the US is an investment that would be a multiple of the costs of building the entire interstate highway system.

Mind you, I'd love it if that were to happen, riding high speed rail is much more pleasant than flying. Speaking as someone who has gone across the continent a few times on Amtrak and enjoyed riding high speed trains in Asia and Europe, it's just hard to see it happening. Recent US infrastructure projects have had massive cost overruns, and there is a seemingly low political appetite for building large infrastructure compared to the 20th century.

[0] https://www.statista.com/statistics/764486/cost-construction...

[1] https://www.wolframalpha.com/input/?i=distance+between+los+a...

> that's almost 400 billion dollars

Great, that's about 2 thirds of the yearly US defense budget! You have the workforce, the discipline, and as a bonus the defense industry can be repurposed for building rails and trains. Once the transition is achieved, you can build such a line every year at no added cost to the taxpayer.

(I know, that's completely unrealistic... it shows the priorities of the US government...)

You know, it's not that long ago people feared nuclear attack daily. I think Americans are projecting their priorities through the budget, not the government.

> Intercontinental and cross continental travel are a bit harder to replace with low carbon alternatives.

But much of it is either for leisure or can be replaced by videoconferencing while saving money.

Regarding leisure, it might feel great to do fast intercontinental travel. But realistically, it is not something which will make you a happy person. Most people who are living today could not afford that luxury and are still living a happy life. Maybe even happier than the average American if their culture is a bit less materialistic.

In the light that it is going to devastate our planet, travel for leisure is not necessary at all.

> One mature oak tree is like 20 kg / year.

All of which will be released again when the oak dies.

Net effect: Zero.

No, that's actually not true. Trees take a very long time to decay.