I’m writing this mostly out of spite.
A couple of weeks ago, my partner and I cancelled our planned trip to Canada for Christmas, because of the uncertainty over Omicron. The rationale was that even if the new variant isn’t as dangerous as we feared, it could be several weeks, if not months, until the facts are known – and in the meantime any international travel would be at the mercy of changing travel rules and general chaos in two countries1.
I tweeted about this decision, citing the uncertainty. Moments later some smug bloke tweeted back at me something to the effect of “at least we can be certain about the carbon emissions of flying to Canada.”
And it was at this point I did something very grown up: I didn’t respond2. I didn’t even leverage the fact that it would have been the first time my partner would see her parents for more than four years to make him feel bad3.
But even if we didn’t have such a sympathetic backstory, this random bloke I am picking on would be wrong to snark. Because here’s the thing: Air travel is good, actually, and climate debates shouldn’t focus on it.
That’s right, I’m writing about climate change again. Be sure to subscribe to my Substack for more incendiary headlines with surprisingly reasonable takes below.
Effort vs Reward
Here’s a chart with a breakdown of greenhouse gas emissions by sector, published by Our World in Data.
That tiny sliver on the bottom right is aviation, which is only responsible for 1.9% of carbon emissions. To be clear, 1.9% is more than zero – but it’s also a lot less than many other sectors, all of which are significantly easier to move toward zero emissions.
Road transport (11.9%), for example, should be relatively easy to decarbonise; we’ve already invented electric cars and battery technologies to make carbon-free road transport possible4.
Similarly, we already have technologies that can reduce emissions from residential (10.9%) and commercial buildings (6.6%), in the form of heat pumps and insulation. And solar panels to make the energy going into them greener.
Even something like “fugitive emissions from energy production” (5.8%) is, in principle, not hard to fix as we could build windmills and nuclear reactors to use instead in drilling for oil and gas.
I can’t claim to have detailed knowledge of every slice of the pie-chart above, but I’d bet there are similar emissions-limiting alternatives available in many cases (various forms of low carbon concrete are increasingly being used in construction, for example).
But what I do know is that aviation is probably the single hardest sector to decarbonise. Why? Because there are, so far, no good alternatives to burning jet fuel for keeping a plane in the air.
The best electric planes are basically the size of a Spitfire, and research into synthetic fuels appears to my untrained eye to be at about the Wright brothers stage. Unlike other sectors, decarbonising air travel isn’t a money or political will problem – it’s a laws of physics problem.
Absolutely Fatuous
Given we can’t make flying greener, the argument goes, should we not fly less? That’s what’s advocated by many environmental activists. For example, the actress Joanna Lumley, who has made TV shows about travelling to Japan, the Caribbean, the Silk Road, Hong Kong and India, advocates for a wartime-style rationing of flights.
At least, that’s what she says when she’s not narrating documentaries about Heathrow Airport or appearing in British Airways’ in-flight safety video.
So why not? Maybe we could limit the number of trips people are allowed to take? Or make the cost of flying prohibitively expensive for the non-Lumleys of the world?
This is a bad idea, because pollution isn’t aviation’s only externality. It does lots of good things too. If I searched hard enough, I could probably find various charts and graphs demonstrating the positive economic impact of air travel. But to tell the truth, this isn’t why I am pro-flying.
The real reason is for the sort of fuzzy, hard to define feelings that connecting people together is good and that the more we get to know our fellow humans, the more we will view ourselves as one people with a common humanity5.
I think it is intuitively true that travel broadens the mind, and that the world would be a better place if more people could experience other cultures and meet people from different backgrounds with different experiences6.
But the way to achieve this is not by making flying – and therefore international travel – harder.
Making Flying Work
“But James, you’ve previously written at length about why climate change is the most important thing, and now you’re promoting air travel? What was that thing you said about the need to prioritise again?”
I absolutely think there’s a question of priorities here. But as per my point above, flying only produces a fraction of global emissions. And in most cases, flying is not easily replaced by another means of travel.
So rather than devote time and energy to moralising about air travel, it would make more sense to prioritise other more fruitful interventions. It would make more sense for environmental campaigners to focus on what gets the most bang for their buck in terms of removing carbon from the atmosphere, rather than what might be fun to argue about on social media.
On this, the campaign group Insulate Britain have absolutely the right cause – environmentalists should want the big story in politics to be intensely boring discussions about the relative merits of different types of insulation, not burning bridges over the most difficult 1.9% of the emissions pie7.
There are, of course, things that we can do around the margins of air travel. It’s insane that anyone should choose to take a plane to travel short distances that could be covered by trains. More high speed rail would put even more journeys into this category8. A carbon tax to offset specific flight costs seems like a reasonable trade-off to me, even though it would increase the price of flying a little.
In any case, the reality is that flying isn’t going away. It’s simply too convenient, so winning political fights to limit air travel more seriously is an inevitable dead-end.
And the impossibility of decarbonising flying also points to another uncomfortable truth: if we’re going to beat climate change, it’s probably going to have to rely on new direct air-capture technology to take CO2 from the atmosphere. Flying isn’t the only sore point – there are other industrial processes which, as part of the process, release carbon into the atmosphere (the production of steel, for instance).
Sadly, air-capture technology is just as new and emergent as electric planes, so it is still early days, but at least we don’t have to bend as many laws of physics to invent it, compared to replacing jet fuel. This is another example of how we’re going to have to build our way out.
So ultimately, I think it’s time to stop demonising air travel. We should instead decarbonise as much of the world as possible, and focus on areas where the biggest gains can be made. We should invest, where we can’t stop the emissions, in the new technologies that can help us offset them. We should aspire to create a net-zero world where everyone gets a chance to travel, not just the rich. And we should stop being preachy on Twitter, lest you wind up annoying a freelance writer enough for him to write a thousand-word essay in response.
Congratulations on reading this far! You made it to the end! If you enjoyed it, please do share it as every share helps the Substack grow. And if you’d like more of This Sort Of Thing, subscribe to my Substack and follow me on Twitter (@Psythor), for real-time hot takes.
Huge thanks again to Allie Dickinson and her editing skillz for eliminating my most egregious errors.
Canada may introduce quarantine requirements, we might need to figure out different tests at short notice, and so on. Plus we may literally catch Omicron en route and infect my partner’s family, which wouldn’t be ideal.
Instead, I let it fester and wrote an entire Substack post having a go at him instead, like a mature adult.
We had been in the habit of going every other Christmas, but in 2019 I somehow persuaded her that we should go to Iowa for the Caucus instead, and that we could visit her parents later. Which seemed like a good idea at the time.
The fact that the person who has improved these technologies so much is notoriously annoying is irrelevant.
I find it particularly bizarre to think that there’s probably a significant overlap between people who think flying is bad and people who are as extremely pro-immigration as I am. How is the latter supposed to work without the former?
No, I don’t think this sort of mind-broadening can be achieved through exclusively technological means. As a technology enthusiast – I am literally a professional technology journalist – I can confirm from my privileged, first-hand experience that reading about, say, China’s rise is one thing, but experiencing the rise of China by taking the bullet train from Beijing to Shanghai is quite another.
Not entirely relevant, but I thought the absolute stupidest criticism of Insulate Britain was broadsheet journalists pointing out the “hypocrisy” of their spokesperson not having insulated his own house, even though his whole point was that insulation is currently too expensive for most people to easily afford and the government should do more to help.
If only there was some sort of Union of European countries we could join that could take a continent-wide view of strategic surface transport corridors and fund rail projects across borders, eh?
I wrote a long comment, copied it to fix a typo, deleted, and then discovered I hadn't actually copied it.
But the summary is:
You can divide air travel into four. One can be replaced by the new battery-electric planes there will be in the 2030s - Heart Aerospace have 200+ orders for their 19-seater, and there are others making similar progress. One can be replaced by high-speed rail. And the other two cannot be replaced as is.
The electrifiable option is short-distance low-demand routes, usually to islands (e.g. flights to Shetland) or to very very low-population areas (e.g. the Australian Outback). These are usually subsidised by city-dwelling taxpayers, and paying a little more for electric planes, especially given the noise-pollution advantages, should not be impossible. They claim these will be in service in 2026, but I don't believe them and expect it to be more like 2030.
The high-speed rail option is short-distance high-demand routes overland. Europe, the US Northeast/Midwest, China, Japan, etc. China has the longest routes and now has a few high-speed sleepers; Europe's routes are getting longer as the national networks get connected together and sleepers make sense for 1000km to 2000km routes, which should cover most of the continent.
The two that can't be replaced are short-distance high-demand routes overseas, such as flights to Ibiza or Majorca; only people who can't fly will be interested in a long ferry journey (it takes far too long).
And the other is longer distances. Anything over about 2000km means at least day and a night on a train, and many such distances include crossing an ocean; ocean liners do exist, but they take a week to cross the Atlantic and two to cross the Pacific. No-one is going to take multi-day journey over an eight hour flight.
Ferries are much more fuel/emissions efficient than flights; liners are a bit better than flying, but nothing to write home about; cruise ships have about the same emissions per passenger-km as flying; trains can potentially be zero emission once we decarbonise electricity which we are doing anyway.
Hi James,
Interesting read!
One thing I’d like to add. Yes, aviation does not represent a large proportion of total CO2 emissions, but aviation’s impact on the climate mostly comes from non-CO2 impacts. Though this would add to your argument that aviation is just incredibly difficult to decarbonise.
Two papers worth checking out that discusses this:
https://www.sciencedirect.com/science/article/pii/S1352231020305689
https://iopscience.iop.org/article/10.1088/1748-9326/ac286e