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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

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?

dottedmag 4y ago
I'm not against air travel for climate reasons, so I can only venture a guess that this is the result of the same psychological mechanism that rivets people attention to air crashes and terrorism, not to car deaths and heart attacks: saliency of former and familiarity of latter.
abyssin 4y ago
All sources of emission are real problems, because the consequences of emissions are catastrophic. The issue is to prioritize which ones to work on first. Flying is nice, but less necessary than many other human activities. Living at a continental or planetary scale is completely unnecessary.
- mcculley 4y ago
  Incentivizing the development of suburbs and lots of driving is unnecessary.
  - PM_me_your_math 4y ago
- mozman 4y ago
  Air travel is a necessity for many, and has quite significant benefits. Goong abroad and learning about people, cultures, and yourself is a difficult thing to quantify but it absolutely pays dividends later in life.
  - abyssin 4y ago
    Sure it pays dividends, but how much, to what cost, and to whom?
    - DocTomoe 4y ago
      Given the countries that travel the least also often are the countries most likely to trigger a war, I'd say we might want to leave that one alone for now and focus on other creators of CO2.
vegetablepotpie 4y ago
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. https://www.carbonbrief.org/aviation-consume-quarter-carbon-budget/ https://www.carbonbrief.org/aviation-consume-quarter-carbon-...
ZeroGravitas 4y ago
Everything is only a small amount of the problem: https://ourworldindata.org/emissions-by-sector https://ourworldindata.org/emissions-by-sector That's why putting a price on emissions helps.
- mcculley 4y ago
  While I think this is useful, I am skeptical of the numbers given the recent satellite measurements.
  - 11235813213455 4y ago
    it can be twice more or twice less, it doesn't change the answer you got above "Everything is only a small amount of the problem" or https://en.wikipedia.org/wiki/Sorites_paradox https://en.wikipedia.org/wiki/Sorites_paradox
    - mcculley 4y ago
      How do we know anything is only a small amount of the problem without good measurements? https://phys.org/news/2022-10-nasa-tool-super-emitters-methane-space.amp https://phys.org/news/2022-10-nasa-tool-super-emitters-metha...
      - 11235813213455 4y ago
        Sure, animal farming is another large emitter (more concentrated of course, so it's more visible in such pictures than a global trafic of airplanes or cars spread around the whole planet surface), another bucket of sand to consider. It's a global optimisation problem, and everything has to be reduced
- DoingIsLearning 4y ago
  I am going to disagree, You are looking at those pie charts graphs by sector/application and indeed it looks fragmented. However once you look at each sector the biggest contributors can be lumped: 1. Energy generation from Coal/Gas 2. Road transport with ICEs. However my gut feeling is that Oil&Gas refinery and extraction are grossly under reporting Methane emissions. So it could be that the chart doesn't show the full picture of GHG.
deleted 4y ago
[deleted]
Mistletoe 4y ago
Both things are bad. Reducing one doesn’t mean you can’t reduce the other and vice versa. We will need to curtain emissions in all sectors to avoid more warming. Also electric cars are coming but electric passenger and cargo planes are very far away or even impossible due to the physics of battery power density. https://tinyurl.com/4uf7v3wm https://tinyurl.com/4uf7v3wm
- mcculley 4y ago
  Obviously. What I don’t understand is why those who claim to be concerned are focused on one and ignoring the other, bigger problem. We should be prioritizing efficiency in emissions.
- cmurf 4y ago
  What's "very far away?" Looks like BETA Technologies has a real airplane, ALIA, that'll potentially be certified next year. They're currently building a manufacturing facility to mass produce it. I think what's very far away is autonomous flight. But IMO farther is autonomous automobiles, because as both pilot and driver, aviation has rules, standards, predictability, integration of a wide assortment of vehicles of flight, training, and thus a far better prepared environment for autonomous. The automobile environment is so haphazard humans make way more mistakes driving than flying.
  - Mistletoe 4y ago
    The cargo and passenger part. No one doubts an electric plane can be made, it’s the ability to lift lots of weight and the batteries. https://www.flightglobal.com/airframers/what-would-it-take-to-power-airliners-with-batteries/145370.article https://www.flightglobal.com/airframers/what-would-it-take-t...
hn_throwaway_99 4y ago
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.
- WanderPanda 4y ago
  4% for only 10-15% of the world population, while most other industries distribute more uniformly. I don't subscribe to the alarmism but the hubris of frequent flyers telling everyone else to cut down emissions triggers me. Most idiotic are the people virtue signalling by not eating meat to offset their air travel as if one category cancels the other while the co2 emissions of one transatlantic round-trip flight are about a lifetime of meat consumption (pork and chicken)...
  - mcculley 4y ago
    Which frequent flyers are telling everyone else to cut down emissions? Do you mean just those rich enough to use private jets?
    - dkarl 4y ago
      Hypocrites. Like a friend of mine who drives an electric car and takes 30+ flights per year including multiple trips across the Atlantic, entirely for pleasure, since selling his business and entering partial retirement. He's a bit of a prig about everything, politics included, so he's a constant source of judgment about people's politics and emissions. I don't doubt he buys carbon offsets for every flight he takes and blames lack of regulation of the carbon offset market for any harm he's causing.
  - 4y ago
it_citizen 4y ago
Aviation currently represents ~2% of total emissions according to our world in data. So yeah, not that much. On the long tun though, we have to reach net zero. And if possible even go into negative carbon emissions. 2% isn't much but there are probably activities much more critical than flying which we could use our carbon offset capabilities. My biggest concern with aviation today are people flying private. It is symbolic but I don't think we will be able to ask people to sacrifice some of their comfort if the wealthiest people are not in the same boat.
- 11235813213455 4y ago
  "~2% of total emissions" .. "not that much" Do you have an idea of how many giga tonnes of CO2/year we're talking about here?
  - it_citizen 4y ago
    What would you do with a number of giga tons in a vacuum? I can't picture what a giga is, nor a ton of CO2. You probably cannot either. What matters is how much it represents in relation with our total emissions (2%) or with other activities we also have to tackle to decide where to put our efforts first. (Or all at once whenever possible) Therefore, I maintain what I say. 2% of the pie doesn't represent that much if we want to achieve net zero. But at some point we will have to tackle it.
  - cagenut 4y ago
    https://ourworldindata.org/uploads/2020/09/Emissions-by-sector-%E2%80%93-pie-charts.png https://ourworldindata.org/uploads/2020/09/Emissions-by-sect... the short answer is "1"
    - 11235813213455 4y ago
      Ok, my own lifestyle is a half tonne per year, so all flights in a year emit 2 billion times more than me, so virtually 25% increase of the world population with my lifestyle as reference
  - 4y ago
nawgz 4y ago
By official stats, aviation is something like 3% of global emissions. Global emissions seem wildly underestimated while aviation emissions are pretty hard to obfuscate. I also couldn't believe when I found out a Learjet 7 seater might get 4MPG while an average US-sized SUV pulls about 12mpg. I thought it would be an order-of-magnitude or two different, not a factor of 3. Trucks are even closer. Americans drive trucks that never go off road or haul or tow. And I think industry is far worse than individuals about emissions. Overall, would I say planes are good for the world? No, not really. But I don't think they're anywhere near the first or most valuable place to focus efforts on
- zemvpferreira 4y ago
  You raise good points, but let's also consider that: -planes travel a lot of miles very quickly. MPG is a fine number, but we should also look at something like total emissions per year of average use. -planes emit around 3% of the global carbon total but serve only around 15% of the global population, unlike most industries. I'm not going to stop flying anytime soon, but let's not kid ourselves about the impact our collective lifestyle has on the rest of the world. Also worth mentioning that measures like carbon taxes, while having many problems, neatly solve what to optimize for when fighting carbon emission. Scale is automatically baked in.
ant6n 4y ago
Air travel is a way for an individual to blow through a significant chunk of their individual annual carbon budget in a couple of hours - and it’s emitted high in the atmosphere where the warning effect is amplified. Globally it doesn’t look so bad because overall, few people use air planes. Among those who use air planes, it looks pretty bad. Also consider that those who advocate against excessive air travel also argue for the use of public transportation, walking and bicycling as a means to replace car travel. For long distance travel, the alternatives aren’t so obvious, that’s why aviation is such a concern.
paulcole 4y ago
> 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? No, because it is obvious that flying less is better for the planet. Replace “flying” with “eating meat”, “driving”, etc. The problem is that all the research in the world won’t get people to change their behavior. The incentives are too strong (it’s fun to go on vacation, meat tastes good, I can make money by selling cars) and the disincentives are too weak (some fish I’ve never seen goes extinct, 50 years from now Miami will be fucked, some people halfway around the world will die, etc.).
deschutes 4y ago
Personal emissions are framed as a moral issue by environmental activists. Those allied with the activists are perceived to be outsized users of air travel. And most air travel is non-essential. Amongst users of air travel, it is a significant source of emissions. A single round-trip across an ocean is on the same magnitude as driving emissions for the average american. The hypocrisy is obvious. Morality and personal responsibility are a terrible foundation for environmentalism.
artonge 4y ago
The issue with aviation should not be framed by its share in total carbon emissions, which appears to be not that much. It's the fact that, in a world where the individual target of CO2 emissions is 2T, there is no room for aviation. Same thing for eating meat more than once a week, or using a personal car. To evaluate your individual CO2 emissions, you can use this simulator: https://nosgestesclimat.fr https://nosgestesclimat.fr
- eastbound 4y ago
  Why is the goal 2T/person? Why do I have the same goal as an Indian or Nepalese person?
  - artonge 4y ago
    What the planet can absorb divided by the number of people. > Why do I have the same goal as an Indian or Nepalese person? I do not understand, why not ?
    - maigret 4y ago
      People fear their living standards will have to be degraded to that level. It’s not true though. Those country comparisons are totally idiotic because they produce the wrong fears. Example: look at that table https://en.wikipedia.org/wiki/List_of_countries_by_carbon_dioxide_emissions_per_capita https://en.wikipedia.org/wiki/List_of_countries_by_carbon_di... , Switzerland is 4.8 tons and a third of the US. I like the US but Switzerland is another scale for quality of life on most metrics. Air travel is one of the few things that’s hard to fix, but for example I can’t understand why everyone won’t buy an EV, that’s basically 99% the same as an ICE car and even better in many aspects. Probably less meat, that will make food cheaper and people will live longer. Else all pretty much the same. Hell, nothing can beat renewables at the moment. They are 4-5x cheaper than fossil fuels. So we’ll be richer with renewables, well save trillions in insurance and I have no clue how people can still thing fossil fuels are the way. Inform yourselves and start to think about the near future, not the past. Stop being a passive fossil fuel lobby repeater.
danhor 4y ago
Car carbon emission are usually around the level of aviation emissions with typical occupancy levels [1]. But Air travel encourages flying much larger distances as opposed to e.g. driving. Without air travel, no sane person would travel to e.g. Asia from Europe a few times per year. Flights over 4000km are 6% of flights but around 52% of emission in europe [1]. Few people will drive 4000km with a car. In my opinion, simply comparing the averages is also not useful. I expect that car occupancy will be higher for distances where flying becomes reasonable, reducing the average emission levels. For example vacation travel most often happens in a group not alone. I also think that the economic benefit of car emissions is higher than plane emissions. Emissions of air travel are commonly often given as CO2 Emissions (around 2% of emissions worldwide), while the complete warming effects are likely around 4% of warming worldwide [2]. Air travel is very unevenly distributed, with most of the population never flying as opposed to e.g. cars (in germany 2/3 of people fly less than once per year with half of them never flying [3], 12% of adults in the US account for 68% for flights takes [5]. In general look at [6] figure 4). Thus a small portion of the population benefits from air travel as opposed to e.g. car travel. The increase in flying for developed countries and the further economic growth in developing countries means that without any intervention flying is expected to increase a lot in the next decades and threathen the paris goal. It's very unlikely that air travel can meaningfully decarbonise in the next decades as opposed to car travel where a broad adoption of electric vehicles is expected in the next decade. The adoption of SAF has been pretty much non-existent up 'till now, contrary to industry promises (and fraught with issues both financial and energy usage) and battery-based solutions are only an option for ultra-short distance flights. Hydrogen based solutions are also very much in the early development phase and IMHO also unlikely to succeed. Long-distance air travel is also without real alternative and can't be rolled back. For example, as air travel gets adopted more broadly, more people live in other countries a longer distance away and regularly visit their families at home. Trying to revert this is basically impossible (people can't see friends and family anymore), so higher adoption is hard to revert. If the population broadly becomes used to international vacations, reducing them in a large way also becomes unpopular. This is continually increases, so social solutions continually get harder. Thus we expect to increase flights (but still with uneven distribution), have little hope for technical solutions for eliminating emissions in the next decades and social solutions will get harder as time goes on. [1]: https://ourworldindata.org/travel-carbon-footprint https://ourworldindata.org/travel-carbon-footprint [2]: https://en.wikipedia.org/wiki/Environmental_effects_of_aviation#Factors https://en.wikipedia.org/wiki/Environmental_effects_of_aviat... [3]: https://www.eurocontrol.int/sites/default/files/2021-02/eurocontrol-data-snapshot-co2-by-distance.pdf https://www.eurocontrol.int/sites/default/files/2021-02/euro... [4]: http://www.mobilitaet-in-deutschland.de/pdf/MiD2017_Tabellenband_Deutschland.pdf http://www.mobilitaet-in-deutschland.de/pdf/MiD2017_Tabellen... page 74 [5]: https://www.sciencedirect.com/science/article/pii/S0959378020307779 https://www.sciencedirect.com/science/article/pii/S095937802... [6]: https://theicct.org/wp-content/uploads/2022/09/global-aviation-frequent-flying-levy-sep22.pdf https://theicct.org/wp-content/uploads/2022/09/global-aviati...
vaylian 4y ago
> 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? 1. As others have said: Many things contribute some non-trivial percentage to climate change. And anything that is above 1% on a global scale is non-trivial. 2. Personal carbon budgets are very quickly exhausted by flying 3. You have to start somewhere to avoid emissions. Some things are harder to avoid than others. I am convinced that 99% of flights are not needed to maintain a good standard of living. It is a low-hanging fruit that we need to pick. The same thing applies to cruise ships.
- saulpw 4y ago
  I agree that cruise ships are an abomination in terms of energy consumption. But wrt flying, the whole "personal carbon budget" thing is a PR move by the major carbon generators to shift responsibility from themselves (who have the ability to make systemic changes) onto individuals (who don't). The planes fly anyway; business travelers make them worthwhile even if they are mostly empty. Your 100kg does not make an appreciable difference, and no significant percentage will stop flying even if most vacationers abstain. See in particular the flights that flew completely empty during early COVID so the airlines could keep their precious airport terminal allocations.
sorenjan 4y ago
Do you happen to fly a lot, and thereby might have a personal reason to not want flying to be as bad as reported?
- mcculley 4y ago
  I don’t think my frequency of air travel is exceptional for my demographic. (Though I did charter a private jet two years ago for a business need. I took a small team to a place without regularly scheduled service. It is not clear to me if it was a net win or loss for carbon emissions given the other routes available.) While I personally choose to live in a walkable downtown for many reasons, including climate impact, I end up having to travel in an automobile often. I think the taxes for this are misaligned to the impact. Personally, I am a proponent of global travel. I think more travel means fewer wars and more benefits for humanity.
  - sorenjan 4y ago
    But part of the problem is that for almost every demographic air travel is not only a big part of each person's total emission budget, it's increasing over time. You're probably flying more than your parents did, and your children have probably flown more now than you had at their age. The aviation industry took a big hit die to the pandemic, but it's been growing steadily up to then[0], and is soon back to pre Covid numbers. People are used to flying several times each year now, while it was considered a luxury to do one flight per year a couple decades ago, and something you did maybe a handful of times in your life a few decades before that. And like most consumption, it's also vastly skewed towards the rich, whether it's the richest in your country or the richest countries in the world. Personally I don't think global travel does much if anything for peace. Most wars are between neighboring countries and are started by leaders that have other reasons than not having visited the other country for doing so. Although travel isn't the issue, fossil fuel is, so instead of framing it as travel is good or bad, it should be about where the energy is coming from. And just like with economy, if you have a certain (carbon) budget, you can't spend more if you already spent all of it. [0] https://www.icao.int/Newsroom/Pages/2021-global-air-passenger-totals-show-improvement.aspx https://www.icao.int/Newsroom/Pages/2021-global-air-passenge...
janef0421 4y ago
The issues with aviation are two-fold: First, the amounts of emissions are very high relative to total passenger throughput. Second, the issue is very difficult to address meaningfully, because heavier-than-air aircraft have inherently high energy requirements that must be fulfilled by very dense, high-quality fuel, which we have no way to sustainably produce in sufficient quantities. This video series explains the issues well: https://www.youtube.com/watch?v=k50qD40p3WU&list=PL_AaC0duf8v8DoO0tv7M8e6CSuqkq30l2 https://www.youtube.com/watch?v=k50qD40p3WU&list=PL_AaC0duf8...
perfunctory 4y ago
> I don’t see why we should be discouraging commercial air travel while allowing individual automobiles to emit so much. How fortunate that nobody is actually suggesting that.

dottedmag 4y ago

I'm not against air travel for climate reasons, so I can only venture a guess that this is the result of the same psychological mechanism that rivets people attention to air crashes and terrorism, not to car deaths and heart attacks: saliency of former and familiarity of latter.

abyssin 4y ago

All sources of emission are real problems, because the consequences of emissions are catastrophic. The issue is to prioritize which ones to work on first. Flying is nice, but less necessary than many other human activities. Living at a continental or planetary scale is completely unnecessary.

mcculley 4y ago
Incentivizing the development of suburbs and lots of driving is unnecessary.
- PM_me_your_math 4y ago
mozman 4y ago
Air travel is a necessity for many, and has quite significant benefits. Goong abroad and learning about people, cultures, and yourself is a difficult thing to quantify but it absolutely pays dividends later in life.
- abyssin 4y ago
  Sure it pays dividends, but how much, to what cost, and to whom?
  - DocTomoe 4y ago
    Given the countries that travel the least also often are the countries most likely to trigger a war, I'd say we might want to leave that one alone for now and focus on other creators of CO2.

vegetablepotpie 4y ago

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. https://www.carbonbrief.org/aviation-consume-quarter-carbon-budget/ https://www.carbonbrief.org/aviation-consume-quarter-carbon-...

ZeroGravitas 4y ago

Everything is only a small amount of the problem: https://ourworldindata.org/emissions-by-sector https://ourworldindata.org/emissions-by-sector That's why putting a price on emissions helps.

mcculley 4y ago
While I think this is useful, I am skeptical of the numbers given the recent satellite measurements.
- 11235813213455 4y ago
  it can be twice more or twice less, it doesn't change the answer you got above "Everything is only a small amount of the problem" or https://en.wikipedia.org/wiki/Sorites_paradox https://en.wikipedia.org/wiki/Sorites_paradox
  - mcculley 4y ago
    How do we know anything is only a small amount of the problem without good measurements? https://phys.org/news/2022-10-nasa-tool-super-emitters-methane-space.amp https://phys.org/news/2022-10-nasa-tool-super-emitters-metha...
    - 11235813213455 4y ago
      Sure, animal farming is another large emitter (more concentrated of course, so it's more visible in such pictures than a global trafic of airplanes or cars spread around the whole planet surface), another bucket of sand to consider. It's a global optimisation problem, and everything has to be reduced
DoingIsLearning 4y ago
I am going to disagree, You are looking at those pie charts graphs by sector/application and indeed it looks fragmented. However once you look at each sector the biggest contributors can be lumped: 1. Energy generation from Coal/Gas 2. Road transport with ICEs. However my gut feeling is that Oil&Gas refinery and extraction are grossly under reporting Methane emissions. So it could be that the chart doesn't show the full picture of GHG.

deleted 4y ago

[deleted]

Mistletoe 4y ago

Both things are bad. Reducing one doesn’t mean you can’t reduce the other and vice versa. We will need to curtain emissions in all sectors to avoid more warming. Also electric cars are coming but electric passenger and cargo planes are very far away or even impossible due to the physics of battery power density. https://tinyurl.com/4uf7v3wm https://tinyurl.com/4uf7v3wm

mcculley 4y ago
Obviously. What I don’t understand is why those who claim to be concerned are focused on one and ignoring the other, bigger problem. We should be prioritizing efficiency in emissions.
cmurf 4y ago
What's "very far away?" Looks like BETA Technologies has a real airplane, ALIA, that'll potentially be certified next year. They're currently building a manufacturing facility to mass produce it. I think what's very far away is autonomous flight. But IMO farther is autonomous automobiles, because as both pilot and driver, aviation has rules, standards, predictability, integration of a wide assortment of vehicles of flight, training, and thus a far better prepared environment for autonomous. The automobile environment is so haphazard humans make way more mistakes driving than flying.
- Mistletoe 4y ago
  The cargo and passenger part. No one doubts an electric plane can be made, it’s the ability to lift lots of weight and the batteries. https://www.flightglobal.com/airframers/what-would-it-take-to-power-airliners-with-batteries/145370.article https://www.flightglobal.com/airframers/what-would-it-take-t...

hn_throwaway_99 4y ago

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.

WanderPanda 4y ago
4% for only 10-15% of the world population, while most other industries distribute more uniformly. I don't subscribe to the alarmism but the hubris of frequent flyers telling everyone else to cut down emissions triggers me. Most idiotic are the people virtue signalling by not eating meat to offset their air travel as if one category cancels the other while the co2 emissions of one transatlantic round-trip flight are about a lifetime of meat consumption (pork and chicken)...
- mcculley 4y ago
  Which frequent flyers are telling everyone else to cut down emissions? Do you mean just those rich enough to use private jets?
  - dkarl 4y ago
    Hypocrites. Like a friend of mine who drives an electric car and takes 30+ flights per year including multiple trips across the Atlantic, entirely for pleasure, since selling his business and entering partial retirement. He's a bit of a prig about everything, politics included, so he's a constant source of judgment about people's politics and emissions. I don't doubt he buys carbon offsets for every flight he takes and blames lack of regulation of the carbon offset market for any harm he's causing.
- 4y ago

it_citizen 4y ago

Aviation currently represents ~2% of total emissions according to our world in data. So yeah, not that much. On the long tun though, we have to reach net zero. And if possible even go into negative carbon emissions. 2% isn't much but there are probably activities much more critical than flying which we could use our carbon offset capabilities. My biggest concern with aviation today are people flying private. It is symbolic but I don't think we will be able to ask people to sacrifice some of their comfort if the wealthiest people are not in the same boat.

11235813213455 4y ago
"~2% of total emissions" .. "not that much" Do you have an idea of how many giga tonnes of CO2/year we're talking about here?
- it_citizen 4y ago
  What would you do with a number of giga tons in a vacuum? I can't picture what a giga is, nor a ton of CO2. You probably cannot either. What matters is how much it represents in relation with our total emissions (2%) or with other activities we also have to tackle to decide where to put our efforts first. (Or all at once whenever possible) Therefore, I maintain what I say. 2% of the pie doesn't represent that much if we want to achieve net zero. But at some point we will have to tackle it.
- cagenut 4y ago
  https://ourworldindata.org/uploads/2020/09/Emissions-by-sector-%E2%80%93-pie-charts.png https://ourworldindata.org/uploads/2020/09/Emissions-by-sect... the short answer is "1"
  - 11235813213455 4y ago
    Ok, my own lifestyle is a half tonne per year, so all flights in a year emit 2 billion times more than me, so virtually 25% increase of the world population with my lifestyle as reference
- 4y ago

nawgz 4y ago

By official stats, aviation is something like 3% of global emissions. Global emissions seem wildly underestimated while aviation emissions are pretty hard to obfuscate. I also couldn't believe when I found out a Learjet 7 seater might get 4MPG while an average US-sized SUV pulls about 12mpg. I thought it would be an order-of-magnitude or two different, not a factor of 3. Trucks are even closer. Americans drive trucks that never go off road or haul or tow. And I think industry is far worse than individuals about emissions. Overall, would I say planes are good for the world? No, not really. But I don't think they're anywhere near the first or most valuable place to focus efforts on

zemvpferreira 4y ago
You raise good points, but let's also consider that: -planes travel a lot of miles very quickly. MPG is a fine number, but we should also look at something like total emissions per year of average use. -planes emit around 3% of the global carbon total but serve only around 15% of the global population, unlike most industries. I'm not going to stop flying anytime soon, but let's not kid ourselves about the impact our collective lifestyle has on the rest of the world. Also worth mentioning that measures like carbon taxes, while having many problems, neatly solve what to optimize for when fighting carbon emission. Scale is automatically baked in.

ant6n 4y ago

Air travel is a way for an individual to blow through a significant chunk of their individual annual carbon budget in a couple of hours - and it’s emitted high in the atmosphere where the warning effect is amplified. Globally it doesn’t look so bad because overall, few people use air planes. Among those who use air planes, it looks pretty bad. Also consider that those who advocate against excessive air travel also argue for the use of public transportation, walking and bicycling as a means to replace car travel. For long distance travel, the alternatives aren’t so obvious, that’s why aviation is such a concern.

paulcole 4y ago

> 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? No, because it is obvious that flying less is better for the planet. Replace “flying” with “eating meat”, “driving”, etc. The problem is that all the research in the world won’t get people to change their behavior. The incentives are too strong (it’s fun to go on vacation, meat tastes good, I can make money by selling cars) and the disincentives are too weak (some fish I’ve never seen goes extinct, 50 years from now Miami will be fucked, some people halfway around the world will die, etc.).

deschutes 4y ago

Personal emissions are framed as a moral issue by environmental activists. Those allied with the activists are perceived to be outsized users of air travel. And most air travel is non-essential. Amongst users of air travel, it is a significant source of emissions. A single round-trip across an ocean is on the same magnitude as driving emissions for the average american. The hypocrisy is obvious. Morality and personal responsibility are a terrible foundation for environmentalism.

artonge 4y ago

The issue with aviation should not be framed by its share in total carbon emissions, which appears to be not that much. It's the fact that, in a world where the individual target of CO2 emissions is 2T, there is no room for aviation. Same thing for eating meat more than once a week, or using a personal car. To evaluate your individual CO2 emissions, you can use this simulator: https://nosgestesclimat.fr https://nosgestesclimat.fr

eastbound 4y ago
Why is the goal 2T/person? Why do I have the same goal as an Indian or Nepalese person?
- artonge 4y ago
  What the planet can absorb divided by the number of people. > Why do I have the same goal as an Indian or Nepalese person? I do not understand, why not ?
  - maigret 4y ago
    People fear their living standards will have to be degraded to that level. It’s not true though. Those country comparisons are totally idiotic because they produce the wrong fears. Example: look at that table https://en.wikipedia.org/wiki/List_of_countries_by_carbon_dioxide_emissions_per_capita https://en.wikipedia.org/wiki/List_of_countries_by_carbon_di... , Switzerland is 4.8 tons and a third of the US. I like the US but Switzerland is another scale for quality of life on most metrics. Air travel is one of the few things that’s hard to fix, but for example I can’t understand why everyone won’t buy an EV, that’s basically 99% the same as an ICE car and even better in many aspects. Probably less meat, that will make food cheaper and people will live longer. Else all pretty much the same. Hell, nothing can beat renewables at the moment. They are 4-5x cheaper than fossil fuels. So we’ll be richer with renewables, well save trillions in insurance and I have no clue how people can still thing fossil fuels are the way. Inform yourselves and start to think about the near future, not the past. Stop being a passive fossil fuel lobby repeater.

danhor 4y ago

Car carbon emission are usually around the level of aviation emissions with typical occupancy levels [1]. But Air travel encourages flying much larger distances as opposed to e.g. driving. Without air travel, no sane person would travel to e.g. Asia from Europe a few times per year. Flights over 4000km are 6% of flights but around 52% of emission in europe [1]. Few people will drive 4000km with a car. In my opinion, simply comparing the averages is also not useful. I expect that car occupancy will be higher for distances where flying becomes reasonable, reducing the average emission levels. For example vacation travel most often happens in a group not alone. I also think that the economic benefit of car emissions is higher than plane emissions. Emissions of air travel are commonly often given as CO2 Emissions (around 2% of emissions worldwide), while the complete warming effects are likely around 4% of warming worldwide [2]. Air travel is very unevenly distributed, with most of the population never flying as opposed to e.g. cars (in germany 2/3 of people fly less than once per year with half of them never flying [3], 12% of adults in the US account for 68% for flights takes [5]. In general look at [6] figure 4). Thus a small portion of the population benefits from air travel as opposed to e.g. car travel. The increase in flying for developed countries and the further economic growth in developing countries means that without any intervention flying is expected to increase a lot in the next decades and threathen the paris goal. It's very unlikely that air travel can meaningfully decarbonise in the next decades as opposed to car travel where a broad adoption of electric vehicles is expected in the next decade. The adoption of SAF has been pretty much non-existent up 'till now, contrary to industry promises (and fraught with issues both financial and energy usage) and battery-based solutions are only an option for ultra-short distance flights. Hydrogen based solutions are also very much in the early development phase and IMHO also unlikely to succeed. Long-distance air travel is also without real alternative and can't be rolled back. For example, as air travel gets adopted more broadly, more people live in other countries a longer distance away and regularly visit their families at home. Trying to revert this is basically impossible (people can't see friends and family anymore), so higher adoption is hard to revert. If the population broadly becomes used to international vacations, reducing them in a large way also becomes unpopular. This is continually increases, so social solutions continually get harder. Thus we expect to increase flights (but still with uneven distribution), have little hope for technical solutions for eliminating emissions in the next decades and social solutions will get harder as time goes on. [1]: https://ourworldindata.org/travel-carbon-footprint https://ourworldindata.org/travel-carbon-footprint [2]: https://en.wikipedia.org/wiki/Environmental_effects_of_aviation#Factors https://en.wikipedia.org/wiki/Environmental_effects_of_aviat... [3]: https://www.eurocontrol.int/sites/default/files/2021-02/eurocontrol-data-snapshot-co2-by-distance.pdf https://www.eurocontrol.int/sites/default/files/2021-02/euro... [4]: http://www.mobilitaet-in-deutschland.de/pdf/MiD2017_Tabellenband_Deutschland.pdf http://www.mobilitaet-in-deutschland.de/pdf/MiD2017_Tabellen... page 74 [5]: https://www.sciencedirect.com/science/article/pii/S0959378020307779 https://www.sciencedirect.com/science/article/pii/S095937802... [6]: https://theicct.org/wp-content/uploads/2022/09/global-aviation-frequent-flying-levy-sep22.pdf https://theicct.org/wp-content/uploads/2022/09/global-aviati...

vaylian 4y ago

> 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? 1. As others have said: Many things contribute some non-trivial percentage to climate change. And anything that is above 1% on a global scale is non-trivial. 2. Personal carbon budgets are very quickly exhausted by flying 3. You have to start somewhere to avoid emissions. Some things are harder to avoid than others. I am convinced that 99% of flights are not needed to maintain a good standard of living. It is a low-hanging fruit that we need to pick. The same thing applies to cruise ships.

saulpw 4y ago
I agree that cruise ships are an abomination in terms of energy consumption. But wrt flying, the whole "personal carbon budget" thing is a PR move by the major carbon generators to shift responsibility from themselves (who have the ability to make systemic changes) onto individuals (who don't). The planes fly anyway; business travelers make them worthwhile even if they are mostly empty. Your 100kg does not make an appreciable difference, and no significant percentage will stop flying even if most vacationers abstain. See in particular the flights that flew completely empty during early COVID so the airlines could keep their precious airport terminal allocations.

sorenjan 4y ago

Do you happen to fly a lot, and thereby might have a personal reason to not want flying to be as bad as reported?

mcculley 4y ago
I don’t think my frequency of air travel is exceptional for my demographic. (Though I did charter a private jet two years ago for a business need. I took a small team to a place without regularly scheduled service. It is not clear to me if it was a net win or loss for carbon emissions given the other routes available.) While I personally choose to live in a walkable downtown for many reasons, including climate impact, I end up having to travel in an automobile often. I think the taxes for this are misaligned to the impact. Personally, I am a proponent of global travel. I think more travel means fewer wars and more benefits for humanity.
- sorenjan 4y ago
  But part of the problem is that for almost every demographic air travel is not only a big part of each person's total emission budget, it's increasing over time. You're probably flying more than your parents did, and your children have probably flown more now than you had at their age. The aviation industry took a big hit die to the pandemic, but it's been growing steadily up to then[0], and is soon back to pre Covid numbers. People are used to flying several times each year now, while it was considered a luxury to do one flight per year a couple decades ago, and something you did maybe a handful of times in your life a few decades before that. And like most consumption, it's also vastly skewed towards the rich, whether it's the richest in your country or the richest countries in the world. Personally I don't think global travel does much if anything for peace. Most wars are between neighboring countries and are started by leaders that have other reasons than not having visited the other country for doing so. Although travel isn't the issue, fossil fuel is, so instead of framing it as travel is good or bad, it should be about where the energy is coming from. And just like with economy, if you have a certain (carbon) budget, you can't spend more if you already spent all of it. [0] https://www.icao.int/Newsroom/Pages/2021-global-air-passenger-totals-show-improvement.aspx https://www.icao.int/Newsroom/Pages/2021-global-air-passenge...

janef0421 4y ago

The issues with aviation are two-fold: First, the amounts of emissions are very high relative to total passenger throughput. Second, the issue is very difficult to address meaningfully, because heavier-than-air aircraft have inherently high energy requirements that must be fulfilled by very dense, high-quality fuel, which we have no way to sustainably produce in sufficient quantities. This video series explains the issues well: https://www.youtube.com/watch?v=k50qD40p3WU&list=PL_AaC0duf8v8DoO0tv7M8e6CSuqkq30l2 https://www.youtube.com/watch?v=k50qD40p3WU&list=PL_AaC0duf8...

perfunctory 4y ago

> I don’t see why we should be discouraging commercial air travel while allowing individual automobiles to emit so much. How fortunate that nobody is actually suggesting that.