I’ve just come back from a holiday in South Africa, and it occurs to me that flying there and back blows my other transport-related emissions for the year out of the water. My partner and I use around 1,000 litres of petrol a year between us, travelling 10,000 km or so. Our CO2-equivalent emissions from this driving are around 2.3 tonnes. On this holiday, though, the return distance is about 28,000 km, or 56,000 km between the two of us (I’m assuming all the flights are in a straight line, to keep things simple). That’s a pretty long way to travel – almost one and a half times around the planet, and probably one of the longest trips you could make from New Zealand, although not that much further than going to Europe.
Long-distance air travel burns a lot of fuel. As a rule of thumb, the level of emissions from this fuel combustion is about the same as a single-occupant car, per passenger kilometre. Aeroplanes are usually at least 60%-70% full, of course, compared to a 20% full car, but it takes rather more energy to sling people through the sky at 900 kilometres an hour. My flights were with Qantas, and – good on them – they’ve got an emissions calculator and ask you if you want to offset your emissions. Here’s the results I got, which seem reasonable.
In total, the calculator tells me that the flights created just over 4 tonnes of emissions per person, which you can then offset at a cost of less than AUD $10/tonne (reflecting low market prices for emissions in the schemes where they are traded, which may not be a true picture of their impact). I didn’t pay the offset – I’m wary of tokenism – but that’s not really what this post is about. I’m wanting to highlight a couple of other issues.
Firstly, the Qantas calculator, like most other ones you might be able to find, is based mainly on the direct emissions from fuel combustion. However, total flight emissions can be quite a lot larger than this. Air travel makes a big contribution to climate change through high-altitude emissions of water vapour, nitrous oxides and other gases which are believed to have a greater impact than they would at ground level. Most (all?) emissions tax/ trading regimes don’t take this into account at the moment, because there’s still a bit of debate around the size of the effect. Presumably this will change at some point, as the science becomes more precise. For now, I’d just note that the estimates you’ll get from these calculators should be considered very much at the low end.
Secondly, long-distance air travel is an amazing thing. You can now get to the other side of the world in less than 24 hours, even with a stopover or two along the way. This has made all sorts of new trips possible, and air travel has grown at an astonishing rate over the last 50 years or so. The lack of substitutes for this rapid, long-range travel makes it all the more important that some solutions are found to the problem of its emissions. Progress is being made – see this post, and I’ll write soon about the potential for biofuels to be used in aviation – but there’s a very long way to go. Realistically, it’s going to be much easier for the world to cut emissions in other areas, rather than aviation.
Thirdly, countries like New Zealand should be very aware of this kind of thing; tourism is a big earner for our economy, and many of those tourists come from distant markets like Europe or America. Greater awareness of climate change issues could affect long-haul travel. South Africa’s in a similar position, if not as remote as NZ – there was a quote I read somewhere which said that, given the problems they have with animal poaching, the only way South Africans would respect and value their wildlife and wilderness areas sufficiently would be if they could build a sustainable eco-tourism economy out of them. As for outbound tourism from NZ, i.e. Kiwis travelling overseas, the reality is that we do a lot of it, and it’s a big part of our lifestyle. I’d argue that this creates a need to focus more on emissions here at home, if we want to keep enjoying the benefits of overseas travel. There are plenty of people who, like me, actually create most of their emissions when going on holiday rather than through what they do at home.