My no-fly year

Why I’m trying not to fly this year

At the start of 2010, I decided I was going to try not to fly this year, for the whole year. Now six months in, I’ve finally got round to blogging about it to explain why.

(I actually published this post briefly about a month ago but I realised I’d miscalculated the figures in the second part of this post. Apologies to people who read the first version as the figures and graphs have now been fixed, and I’ve re-written most of the article based on more up-to-date information.)

The main reason I’m trying to avoid flying as much as possible is because of the disproportionate impact that flying has on climate change compared with other forms of transport like trains or cars. Planes, like cars and most UK trains, emit carbon dioxide (CO2) which can be measured in metric tonnes. The combustion of aeroplane fuel, however, emits other gases too: nitrogen oxides and water vapour. At high altitudes (which is where most aeroplane emissions are made), these gases have an increased impact on the climate compared with at ground level1.

Travelling by plane can produce the same emissions per person as travelling the same distance by car but you typically travel further in an aeroplane than you would by car or train so the amount of carbon dioxide emitted is greater before you even start to include the effect of the other emissions at altitude.

How flying compares with other activities

Currently, each person in the UK, on average, is responsible for about 9 tonnes of carbon dioxide (and the CO2 equivalent in other greenhouse gases) per year2. For the sake of comparison with other countries, the USA emits about 19 tonnes, France emits about 6 tonnes, China about 4.5 tonnes, and India about 1 tonne per person3.

Although the UK looks quite virtuous in comparison with the USA (see the graph in 3), now compare the UK with China and India. And remember that the 9 tonnes doesn’t include all the stuff we import to the UK that is manufactured in other countries, such as China and, therefore, is included in China’s accounts.

When you include the things we import, plus flying (currently not included in national environmental accounts), the UK’s average person emits nearly 14 tonnes of CO2 and equivalent greenhouse gases (collectively known as CO2e)4. However,  this being an average means, of course, that some people emit more than that and some people less than that. Typically, the more money we have, the more greenhouse gases we cause to be emitted.

Aeroplane emissions account for about 1.2 tonnes of CO2e per person4 but are rapidly increasing1. For the sake of comparison, home heating and car travel each account for about 1.2 tonnes of CO2e per person per year. Also, only about half the population of the UK takes 1 or more return flights every year.

Although some effects of human-induced climate change are too late to reverse (and we’ll have to adapt to those changes), we can avoid more significant increases in global temperature (2-4 degrees Celsius) if we significantly reduce our CO2e emissions. In the UK, this means reducing our emissions by about 75-80%4,5. This sounds a lot but it’s possible if we reduce to almost zero our use of fossil fuels, such as by reducing the amount of energy we use to heat our homes, changing to using electric instead of petrol/diesel cars, and changing our electricity sources from coal and gas to mostly renewable energy sources (potentially including nuclear energy)8.

Which brings us back to aeroplanes, which run on kerosene, which is a fossil fuel. Although there is research into alternative fuels for flight, there’s no alternative at the moment. And even if there were already, planes have long lifespans and so would be unlikely to be replaced with newer more efficient versions very quickly.

So, aeroplanes are running on fossil fuels for the foreseeable future, aeroplane journeys tend to be over longer distances than typical car journeys (one return flight from London to New York is nearly 7000 miles6, compared with the UK average of 9,000 miles that a car would travel in a whole year), aeroplane emissions have a greater impact because they are at high altitude (one return flight from London to New York emits about 1.5 tonnes CO2e per person6 over 7000 miles, compared with 1.2 tonnes CO2e for 9000 miles of car travel per year), and even the emissions from short-haul flights cause about twice as much impact on the climate as the same emissions would on the ground.

So, the single most significant thing an individual can do to reduce their impact on climate change is to stop flying.

All my flights in my life…ever

When I started learning about the human impact on climate change in terms of numbers, I wondered about the impact of flights I’ve made. Last year, although I didn’t really think about it in any detail, I was vaguely aware that I’d taken quite a few short-haul flights throughout the year. And I knew that the previous year, I’d flown to the U.S. for a conference as well as some flights within Europe. Through a combination of saved emails (flight booking confirmations) and memory, I constructed a list of all the flights I’ve ever made since my first in 1999.

The following graph shows the 37 flights I’ve taken, by year, since 1999 (click the image to see a larger version):

And the next graph shows my carbon dioxide (including equivalent greenhouse gas) emissions for those flights:

The four years with large spikes were the years I took return long-haul flights to the USA (twice for work, once for a wedding, and once for a non-work conference). Other than that, the flights have all been within Europe, including six within the UK (between Southampton and Scotland).

So why has the number of flights I’ve taken increased so much in the past few years (specifically, since 2003)? Mainly, it’s a result of getting a job (I was a student until 2001) so I could now afford to fly. Also, post-university, friends started getting married and inviting us to weddings. Two of the long-haul flights, and four of the six internal UK flights, are wedding-related. There was also the christening of my godson which I’m counting as a wedding-type of event here and involved a return-flight to Europe.

Here’s a breakdown of the CO2 emissions by the primary reasons for taking the flights (the number in parentheses in the legend shows the number of actual flights per reason):

The greatest proportion of emissions was due to flights for work, that’s not too surprising as I work for an US company but only four of the eight flights making up that large segment were actually long-haul. Two were short-hauls within the US, and two were short-hauls to Europe, which just goes to show how big an impact transatlantic flights alone have on greenhouse gas emissions. The two next largest categories of CO2 emissions are Conferences (non-work-related) and Weddings, both of which include one return flight to the US. In contrast, although the greatest number of flights is down to holidays, they’ve all been in Europe so the CO2 emissions per flight, and overall, are lower.

Bearing that in mind, my 2005 and 2008 flights produced nearly 2.5-3.0 tonnes of CO2e per year, which is twice as much as the average UK person. And that’s before I even start counting home energy usage, car travel, and so on.

In conclusion…

The lesson at the crudest (and probably most obvious) level, is to avoid going to destinations that require long-haul flights. That would imply that short-haul flights are mostly okay then? Well, not really. The key thing with short-haul flights is that there are almost always alternative ways to travel that same distance that have a much smaller impact on climate change, making it often unnecessary to fly. Even when the amount of CO2 per person works out the same by car as for flying (you can fit more people in a plane than in a car, for instance), the effect of that CO2 and other emissions at high altitude is worse than at ground level. It’s possible, for example, to get from the UK to the South of France by train – which is especially good for the CO2e accounts when you consider that France’s high-speed train (TGV) is almost carbon neutral as it runs on electricity mostly from nuclear sources (not fossil fuels like UK electricity)5, and the Eurostar is carbon neutral through an active project to reduce carbon dioxide emissions as much as possible and to offset the rest7.

I can’t swear I’ll never go to the US (or other long-haul destinations) again, and there’s not really an alternative way to get there other than flying. I wouldn’t take that decision lightly though. For this year though, during which I’m not flying at all, that means the US and other destinations for which there is no alternative are out, and I can only go to places to which I can find an alternative mode of transport.

If you’re interested in knowing how I calculated my flight emissions for the graphs above, and the exact figures used, I’ll be showing my workings in a separate blog post soon.


1 Calculating the Environmental Impact of Aviation Emissions 2nd Edition, Dr Christian N. Jardine. Published by Environmental Change Institute, University of Oxford, for Climate Care, 2008.

2 CO2 Emissions Per Captia, UK. Google Public Data. Source of data: World Bank, World Development Indicators, 2007. Accessed on 4th July 2010.

3 CO2 Emissions Per Capita, US, UK, France, China, India. Google Public Data. Source of data: World Bank, World Development Indicators, 2007. Accessed on 4th July 2010.

4 How To Live A Low-carbon Life, 2nd EditionChris Goodall. Published by Earthscan Publications Ltd, 2010.

5 The Hot Topic. Gabrielle Walker and Sir David King. Published by Bloomsbury Publishing, London, UK, 2007.

6 Mileage for a return journey between London Heathrow and New York’s JFK airports calculated using Climate Care’s online calculator at on 4th July 2010.

7Eurostar’s Tread Lightly project: Accessed on 4th July 2010.

8 Sustainable Energy: Without the Hot Air, David MacKay. Published by UIT Cambridge, 2008.

10 thoughts on “My no-fly year

  1. I am interested in your workings – I meant to ask you on twitter when you tweeted about this a while back. I’m glad I saved the carbon electrons now.

    The relatively new book “How Bad Are Bananas?: The carbon footprint of everything” might be interesting as well. Like you say, knowing has worse carbon footprint is difficult.

    Could you put any more numbers on “a massive amount more than individuals in India”? I’m concerned that if we’re twice that of developing countries like China, then a 75% reduction will be hard work. Comparing to India might set me more at ease!

  2. I wouldn’t make China out to be so virtuous based solely on their smaller per capita output.

    UK population = 61.4m (in 2008) = ~ 577.16m tons
    CN population = 1324.6m (in 2008) = ~ 6.159bn tons

    I know the years don’t quite tally, but I’ve used the same World Bank public data from Google:

    The UK is largely industrialised while large swathes of China will still be rural and egrarian, and while we in the UK are at least aware of our carbon output (although it shouldn’t be the only metric by which we live) and some are doing something about it, China’s output will undoubtedly only increase.

  3. Neuro makes a very good point – if we drop the UK carbon output by 80% (which would be extremely impressive), it’d be completely cancelled out by just a 7.5% increase in China’s output.

    Obviously it’s still a good target to pursue as it all helps and would give us more of a leg to stand on asking other countries to do the same, but it’s a bit depressing.

  4. Yes, I agree that would be depressing! 🙂

    I think China (and other developing nations) are aware of all this though and aren’t just blindly increasing their emissions without a care. The point that China (and other countries) are absorbing a huge chunk of Western emissions is still valid. Part of the UK’s efforts could be in helping reduce UK emissions that we ‘outsource’ to places like China. Not just (as we are now, I think) reducing our own domestic emissions by shuffling them off to other countries.

    I agree that leading the way gives us a good leg to stand on. It also reduces the amount of CO2 etc in the atmosphere that the UK is responsible for in total. I think CO2 hangs around in the atmosphere for up to a century, so a lot of what’s up there at the moment is down to us and other similarly long-time industrialised countries. Which, again, makes it morally difficult to throw our hands up about China’s recent entry to the party.

  5. Roger/neuro
    Surely the per capita data is far more relevant than per country? We are much greater emitters than only twice that of developing countries, and need to urgently move back to being more rural & agrarian;
    UK 2006, 9.4t, China 4.6t, India 1.3t (US 19.0t), whereas gives emissions per country, set against per capita & emission intesity (per GDP).
    Contraction & Convergence is Aubrey Newmans amazing methodology for tackling this globally –, ie. China SHOULD be allowed to increase their output, whilst we need to contract, until an equitable balance is achieved.

    My research into plane emissions shows a wide range of conflicting figures on carbon cost per mile, but as my fave exponent on European travel is the man in seat 61, I give his figures from
    – London to Paris, by plane 3.5 hours = 244 Kg/CO2, by Eurostar 2.75 hour = 22 Kg/CO2
    – London to Edinburgh, plane 3.5 hours = 193 Kg/CO2, train 4.5 hours = 24 Kg/CO2
    – London to Nice, plane 4 hours = 250 Kg/CO2, by Eurostar+TGV, 8 hours = 36 Kg/CO2

    I’ve pledged not to fly again – I would only break this promise for emergencies & my sis lives in Australia so its been a difficult pledge to make. However, if we don’t start living in a low-carbon way ourselves, how will we ever teach our kids how to live within the future restrictions of life with really expensive oil, financial stresses & climate change?

    I’m also intrigued enough to work out all my flights taken, ever! (only one trip to Oz)

    As for Anton, yes, that’s true …

    [ref for figures:
    The figures for aviation emissions are derived from the International Civil Aviation Organization (ICAO) emissions calculator and Civil Aviation Authority CAA) data, and are based on actual load factors achieved during 2007(latest available data). Eurostar’s carbon dioxide emissions are derived from analysis conducted by Paul Watkiss Associates in February 2009. They are based on actual supplier mix of electricity and actual load factors achieved during 2008 (first full year of services on High Speed 1).

    Radiative Forcing Index – the non CO2 climatic effect of aviation – has not been added to the aviation emissions calculations.]

  6. Katy,

    LHR-EDI takes between 1h 20m to 1h 35m (can change variable on weather, traffic and wind) on BA, not 3.5 hours.

    KGX-EDB takes between 4h 20m to 4h 50m (variable on traffic, etc) on East Coast.

    If you’re going to inflate air travel times with the periphery of actually travelling (getting to the place of departure, getting from the entry point to a seat on the vehicle, the vehicle actually departing, etc), then you must do the same with the train too, otherwise it’s not a fair equation.

    As for your comment re per capita, all it takes is for the largely rural nature of China to become more urban, Chinese car use to increase, electricity use to increase, manufacturing to increase, and their national output will go through the roof. You absolutely have to take the size of the population into account. The Netherland Antille’s per capita output is 22.8 tons, but with a population of only 195,253, their total output is a relatively small 4.45m tons. If China’s per capita output was 22.8 tons rather than 4.6 tons, their output would skyrocket to 30.2bn tons. See my point?

  7. If there were only 10 people on the planet, they could use as much resource as they wanted for ever without any impact. The more people there are the less resources we can each use. So the biggest environmentally damaging thing to do is to have more kids!

  8. neuro
    I’m absolutely certain that the Man in Seat 61 took all the peripheral time into account in his calculations – take a look at his awesome website.

    Of course I ‘get your point’, but we are talking about the whole planet here, not about one country having more rights than others. My point about China et al is that they must be allowed to increase their emissions, whilst we should be encouraged (forced!) to reduce ours. This is the whole principal of Contraction & Convergence. We all have an equal right to our planets resources, no matter where we live. However we do need to get down to ‘One Planet Living’.

    If we were all living in the benign way (in terms of emissions) that some ‘underdeveloped’ (but happy!) countries are then producing more offspring wouldn’t be the biggest issue. In the developed countries like ours it consumption of resources and needles waste that we need to curb. We have been brought up to believe that belongings = status & that consumption & growth are desirable. Watch – it made me really think about the madness we have become used to.

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