Additionally, her environmental impact would only really be true if her flight was cancelled as a result of her taking the train. Is there evidence that this happened?
If a plane has 200 seats, and 400 people are willing to fly a given route, the airline sends 2 planes. Make it 401 people, they'll send three a day. That means each person who flies or doesn't brings the count closer to the next threshold, where the number of planes flying changes.
Of course, this is oversimplified, not as instant as I described it, there are price politics and what not, but you can still very much say the climate footprint of each passenger is (total plane print/passengers). The idea is not to make super accurate global calculations but to quantify individual behaviour without employing a super computer.
> If a plane has 200 seats, and 400 people are willing to fly a given route, the airline sends 2 planes. Make it 401 people, they'll send three a day.
No. They will send one with 400 seats in the first scenario, and possibly two with 300 seats or one with 400 and one with 100 seats in the second scenario.
It's not a more complicated scenario. IIRC a company loses money if the plane is not at least half full. So there's no chance a company will send two planes if the second one will only haul 1 or two passengers.
If the demand increases and they are always booked to capacity, they will send a bigger plane first.
If the demand decreases, and they are never booked to full capacity, they will send a smaller plane or will cancel the flight.
> there are thresholds which everybody (not) flying influences
There are. But, unfortunately, flying still beats everything else on convenience for anything but the shortest trips. And even on shortest trips the distinction between a train trip and a flight might not be that obvious (if we take into consideration convenience alone).
You're claiming the argument is wrong, then supporting it again.
The person(s) who go over or under the threshold are the ones that make a difference. If thresholds aren't breached by the amount of people changing route, then there is not a very significant difference.
As you indeed state:
"but you can still very much say the climate footprint of each passenger is (total plane print/passengers)"
You can indeed say as much, but "this is oversimplified".
Just to be clear - I am not arguing that we should not pick routes responsibly, with the environment in mind. I am merely trying to ensure we are clearer about what impacts we are actually making and that we are considering all the impacts and not just doing a simple calculation that actually misses out the many complexities of transport.
In transport, we have learnt over the past century to not use aggregate models, as they do not provide the same detail and results as disaggregate models[p.18 Modelling Transport 4th Edition Ortuzar & Willumsen]. We should not lower our standards when discussing emissions and pollution.
This article above is a very worrying case - where the reader is encouraged to shame people for flying, without showing necessary statistics as to whether flying is indeed much worse than other transportation methods.
This is some seriously ridiculous mental gymnastics (continuum fallacy). Someone who never flies is now responsible for the environmental impact of those who fly, because specifically their lack of flying is not canceling any flights (or preventing any flights from happening)?
Certainly not. Responsibility is a very complex issue, especially if you devolve it to the users, rather than keeping it in the hands of the managers/operators.
But even if we assume a large part of responsibility rests in the users, then the responsibility would clearly be only held by those planning to make the trip and deciding which form of transport to use (potential users).
If it becomes a trend, that will be good if indeed the efficiencies are true. As stated earlier, it is unclear how the calculations are made and whether the actual total emissions cost was lowered.
The whole flight does not need to be cancelled. Underselling flights are often replaced with smaller aircraft. One person might not make a difference, but if 10 or 20 cancel, an A321 may get replaced by A320 or A319, which are lighter and burn less fuel.
Switching to a smaller aircraft isn't necessarily good for the environment.
For example the A319 burns 5%/less fuel than the A320 but has 15% fewer seats, in common configuration. So the per-seat emissions are worse than if they had sold the remaining A320 seats at cost
Yes, this all sounds like a complicated way to say "obviously we've got to reduce air travel, but I'm not going to fly less, because what can one person do".
This should be a named fallacy.
Works in all sorts of situations: "obviously I have to eat less, but not this mealtime".
There is a difference between decision making and calculations of change.
I am certainly not arguing that decisions shouldn't be made responsibly. I am merely trying to point out that the calculations that have been made are simplistic.
That is certainly true, but from the scale of the calculations, I am assuming that ecopassenger.com is not just calculating that difference, but the overall emmission cost as a ratio of flight.
That is not what I am arguing at all. I am merely pointing out that it is unclear as to what the ecopassenger.com website is calculating and what we can gather from this information.
"Environmental website ecopassenger.org calculates that Greta’s train journey to Davos, Switzerland, emitted just 44 kilograms of CO2, compared to an expected 262 kilograms had gone by plane."
They are trying to suggest that she chose this trip, because it is environmentally better, but actually irrespective of her choice, there was most likely a total of emmission of 306kg of CO2.
There could certainly a benefit, if the aim is to just fund transport that is more efficient and less pollutant. However, as mentioned earlier, it is unclear how the calculation is made and whether it is actually true when considering the wider requirements for the services - e.g. maintenance.
That's interesting. My assumption was that they were using individual examples to show the aggregate effect of large numbers of people making such choices, at a scale great enough to influence flight planning, but in a way that seems relevant to us as individuals. After all, there are hundreds of millions of people in Europe. If 1% of them make a small but material change in their travel habits that's millions of people taking fewer flights, which clearly could have a material effect on flight schedules. It would never have occurred to me that, in fact, they literally meant us to think that one person making that choice would individually have that effect.
A passenger jet burns 10-15 liters of fuel pr km. Stockholm-Geneva is about 1600 km, so 3200 km round trip. So the numbers seem at least to be in the right ball park.
