Air travel contributes to about 2.5% of greenhouse gas emissions and is responsible for about 3.5% of anthropogenic warming [1]. In my opinion, there is an outsized amount of public outrage going on and we should be directing this outrage toward larger sources of anthropogenic warming. There is only so much people can take before they get fatigued. "Spending" this outrage on something that is only 3.5% of the problem seems wasteful.
Air travel accounted for 2.5% of CO2 emissions in 2020 and closer to around 3.5% of total contribution to global warming.[1]
Only 11% of the world's population travelled by air in 2018, with at most 4% taking international flights, and 1% of the world's population accounting for more than half of the total emissions.[2]
Passenger air travel is projected to grow by about 44% by 2050,[3] and will probably take up an even more substantial slice of overall emissions by then because technologies to decarbonize air travel (other than direct carbon capture) do not yet exist.
The argument you are making is probably least compelling when applied to air travel compared to any other form of consumerism, and HN's readership (generally speaking) is uniquely culpable here.
Not claiming I am against air travel, but the point often made is that the growth rate of aviation means that it will consume ever higher slices of the “carbon budget”.
> His [Dr Joeri Rogelj] calculations suggest aviation emissions between 2015 to 2050 will consume 27% of the remaining carbon budget to have a decent chance of keeping global temperature rise below 1.5C above preindustrial levels.
While I am completely convinced that humans are changing the climate, I am not convinced that air travel is the big contributor claimed by many. We are only now getting satellite evidence of the amount of methane venting being done industrially, which seems to be a bigger contributor per unit of mass emitted.
I live in the U.S., which has many big automobiles transporting just one person. They are a much bigger emitter of carbon per person per unit of distance traveled. I don’t see why we should be discouraging commercial air travel while allowing individual automobiles to emit so much.
Those of you who are against air travel for climate reasons, can you share a source that has convinced you that it is a real problem?
My understanding is that research suggests airplane emissions make a disproportionate contribution to the climate crisis because they are released at high altitude, but I'm not an expert.
Also, it seems intuitively obvious that moving N kg by plane is vastly less efficient than other forms of transport like rail or ocean shipping. We should be doing fewer energy-inefficient things and more efficient things.
We have to drastically reduce air travel to cope with global warming and excess CO2. It's pretty unethical to fly more than a few times a year. CO2 injected into the upper atmosphere causes 2-3x warming vs ground level CO2 emissions.
Keep in mind that as a fraction of emissions, air travel is actually quite small, about 2-3% [1] (and this is from a harsh article). There's some concern that as the industry grows (roughly 5% a year) and other sectors decarbonize, air travel will consume a larger fraction of remaining "carbon budget" (25-50% depending on where you look).
Clearly as the denominator shrinks, and the numerator grows even slowly, percentage increases. That said, it's probably not the main issue in in climate change or even close to it. Other sectors such as ground transport, industrial heat (cement, steel etc.), agriculture (primarily fertilizer) and other fixed sources (buildings/homes) are a bigger deal.
If we end up with airlines as the last carbon source, that's probably OK if we deal with the rest. 25% or even 50% of remaining budget is fine if the rest of the (easier) problems get solved. Air travel is uniquely hard, let's get the easier stuff first.
Thanks for re-iterating this. Granted, due to where the emissions take place, air travel is slightly stronger/higher but I feel like the sole focus on air travel is an annoying feature of a lot of climate-change discussions. It's something we really don't have many technically or economically viable alternatives for yet.
Why don't climate-change measures and discussions focus on the other 95%+ of sources that are easier to address?
If the problem with air travel is emissions then we ought to work on alternative fuels. That's the positive thing to do.
There is too much finger pointing, though. Globally, air travel accounts for only a small proportion of emissions, which means it gets a disproportionate amount of attention at the expense of more important things.
Most air travel is unethical in the current global warming situation, and it's growing at an alarming pace. Governments should try to reverse the trend ASAP.
We're at the point where the only way to have a real impact on warming is large, global changes in the industrial economy. To pretend that anyone's individual behavior matters only obscures this already difficult-to-discuss issue even further. Aviation is not a significant contributor to global warming (at most 4.9% of the impact according to the ICCC), and if everyone stopped traveling to conferences tomorrow, I suspect it would have a minimal impact on airline schedules.
I get that people want to have a sense of agency, but framing the problem as a question of individual choice is counterproductive.
I tend to agree. Air travel contributes around 4% to increased global warming. That is substantial for a single industry. That said, of all industries, it feels like the practical difficulties of reducing that footprint are enormously more difficult than other industries. Air travel is just enormously energy intensive and has unique difficulties in switching to carbon-free energy that other industries do not.
I think some regulations are great, like the prohibition against short haul flights in France that the article mentions. But I think overall efforts to reduce global warming should be targeted in ways that give the "biggest bang for the buck", and aviation-specific changes ain't it.
Airliners account for 2.5% of global CO2 emissions [1], yet we are working to ban passenger air travel to protect the climate. 5-9% is huge in comparison, and we should legislate restrictions on wasteful computing before the climate emergency gets any worse.
Fair point that as a society there may be more urgent things to focus on.
However, counterpoints:
1. The carbon footprint of flying is expected to triple by 2050. It will still not be the worst sector, but it is getting worse quickly, and it makes sense to avoid that.
2. Flying less is one of the easiest ways for an individual to reduce their carbon footprint. Just taking one less flight a year makes a dent in your total footprint. There aren't many other actions an individual can take that, if all individuals took them, would make an impact.
Disincentivizing air travel could have a big impact on climate change as well. I don't understand why those who want to do something about climate change still fly around the country/world like its nothing. A single plane ride from NYC to LA emits about 20% of the greenhouse gases your vehicle does each YEAR. 5 trips in one year and you've essentially been running a second car for that year. [0]
If you care about climate change and you still fly I can't take you seriously.
Aviation is responsible for 2% of carbon emissions but was growing at 4% per year.
Aviation is responsible for the mass tourism that drives people out of cities to make way for airbnb's. This increases their commute. It also increases real estate speculation, i.e. more construction of houses (cement alone accounts for another 2% of emissions).
We cannot take a reductionist view of the problem. Mass tourism was one of the biggest environmental problems and was based on aviation.
Travelling by air is a privilege that only a small percentage of the population has access to. If everyone did that we would quickly exhaust our carbon budget.
I get what you're saying about limiting air travel, but let's look at the bigger picture.
Commercial flights make up around 2% of global carbon emissions, so forcing people like me not to travel is not going to make a significant dent in climate change. Focusing on industries and companies that are responsible for the bulk of emissions might be a better way to go.
Rather than trying to control individuals, we need to hold industries and corporations accountable. Pushing for policies that target high-emitting sectors like energy, transportation, and agriculture can create real change. By tackling the main culprits, we have a better shot at making a difference.
Air transportation is a major contributor to CO2, if you limit the scope to the people who use it. It is estimated that about 80% of the world's adults have never taken a flight, and 94% of the world's adults have not taken a flight in over a year.
So, the real picture is that this 2.5% of global CO2 emissions are caused by as few as 6% of the population, who also are incidentally the richest and bear a high personal carbon footprint in other domains than transportation.
Also please remember that the aviation sector is growing, and therefore its global contribution to GHG emissions will grow as well in the future. Discounting the carbon footprint of the aviation sector based on today's numbers is a mistake.
If you do not want to impede on your ability to travel, you shouldn't object to it for the 94% of the population that want the same thing as you, and when it becomes available to them the aviation sector's emissions will increase 15-fold.
[1]: https://www.eesi.org/papers/view/fact-sheet-the-growth-in-gr...
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