I have recently been following some of the work of a colleague of mine, Kjartan, who is a recently graduated PhD working in my university’s Industrial Ecology department.
He has an impressive number of publications behind him for someone who’s just finished his PhD and has been quite active in the media lately (both local newspaper, TV and an university research magazine). He works with input-output analysis, which is not my field either so I can’t explain it, but basically it allows him to get a bigger picture of the Norwegian average carbon footprint.
He published a graph earlier this year (in the Norwegian magazine Gemini) that gives a bit of a breakdown of how the consumption habits of the average Norwegian household can be divided up.
The biggest contributor by a good margin is transport related emissions. This is helpfully called ‘transport’ in Norwegian. 🙂
My emissions are pretty different from the typical person, as even though I don’t own any motorised vehicles, I travel by plane much more than average (which is of course my principle aim in reducing through this blog). I have known since I tried a crude calculation myself as a part of a climate change subject in my undergraduate studies that my two return flights from Perth to Melbourne each year were causing something like 80% of all my emissions. There is a good chance I underestimated many of the things that Kjartan has included, but given my even higher number of flights today it’s pretty likely that it is worse.
Since I now have some decent evidence to show that transport is the biggest contributor to emissions for the average Norwegian, and not just myself, then this lends credit to my focus on this area. (Outside of transport I do also try to eat less red meat, and buy local foods – Meatfree Monday is worth a shot if this is new to you!).
Since I am presently working with transport I can pretend also that as I write this blog post I am doing work. It’s not true of course but it helps me sleep at night.
For this post, it’s long distance travel I’m looking at.
This year has been exceptional in many ways for my long distance travel. Let’s firstly use the definition of journeys over 100km in length as long distance, since this is what the National Travel Survey (in Norway) uses. Of course virtually all commercial flights fit into this category, and in the past 12 months I have taken 26 take-offs and landings. 4 of these flights involved a single stopover, all of which occurred in Oslo. This is thanks to Oslo’s role as a hub for SAS flights, whilst Trondheim has relatively fewer direct connections to the rest of Europe.
Of course by grouping these 26 flights we get to see a fairly clear pattern based showing the fuel efficiency based on the total length of flight. But don’t get confused. Flying long haul may have lower emissions per km, but these are likely to be some of the biggest contributors to your total footprint. The good thing about short haul flights is that they are possible to replace with other means!
So 26 flights is quite a bit, or maybe 22 depending on whether you want to count stopovers (probably should given their impact).
Now lets consider other long distance journeys – especially those that could have been flown (those for which a commercial airline route exists with or without stopover, without excessive additional distance). In 2015, I made 16 such flyable trips with ground transport, at an average distance of 643km (using some approximations from Rome2Rio). But the average distance ‘as the crow flies’ or directly from origin to destination brings this down to 458km. In addition to the flyable journeys are about 10 or so journeys that meet the >100km distance criterion, but I haven’t included these for analysis (this time).
Of these 16 journeys, one actually had higher CO2 than the officially claimed CO2 output from flying (Trondheim to Bodø – a relatively lowly utilised diesel train). With this exception all the other journeys consumed less CO2. But they are not CO2 neutral – except for maybe journeys made with Swedish Railways if their environmental calculator is to be trusted.
Adding up the total savings of CO2 gives a value of 757kg. In other words compared to flying, my ground transport behaviour has saved 22% of my year’s emissions.
- Emissions from flying (17100km): 2267kg
- Emissions from ground transport (10300km on ground): 420kg
- Emissions if I had taken all the 16 ground transport as flights (7300km): 1177kg.
This means that the long distance ground transport I have taken this year has been on average emitting 36% of the equivalent journeys by air. It would mean a CO2 intensity (per flying km – to compare apples with apples) of 57g CO2/km. Just under half of the emission intensity of my European flights this year. And hopefully as electricity sources get greener, electrification of rail transport continues, and fuel efficiency of ferries improves (with much greater probability than equivalent improvements in plane technology), then this figure should only get better!