There is much talk these days of reducing our ‘carbon footprints’. But what does this mean in practice? Here is a list of things that I (and others) consider to be important if we are to take control of this important aspect of our lives.
From the point of view of climate change, flying is highly destructive and must be minimised.
Taking into account the fact that emissions at high altitude are more damaging (in that they trap more heat), flying is about seven or eight times as polluting as going by rail, and three times as polluting as driving.
- A single person flying from New York to Florida and back is responsible for 1.2 tonnes of CO2 equivalent.
- To fly from the UK to Spain and back produces 0.6 tonnes.
- Flying the 400 miles from London to Edinburgh produces the equivalent of 0.39 tonnes of CO2. The rail journey, which takes about 5 hours, produces 0.05 tonnes of CO2. Driving produces 0.14 tonnes.
To put this in context, if we are to control climate change in an equitable way, global per capita emissions will have to be around 2 tonnes a year.
There are no current technological solutions to aviation emissions, though minor progress has been made on making aircraft more fuel-efficient. The use of biofuel by aircraft is being promoted and should be supported, provided that the biofuel used has a positive carbon footprint. However, the need to feed the world population means that biofuel should not be used wastefully. For example, it should not be used for surface transport, which can and should run on electricity. However, it should be used to enable people to fly for important reasons – for work when necessary (though this should also be reduced), to visit family or close friends, to experience new cultures and so on. Flying to lie on a beach or get drunk on cheap alcohol (or both) is not in this category.
So, holiday near your home and discover how beautiful your own country can be.
You should also minimize driving. Walk, cycle, use public transport or car-share whenever possible. If you have to drive, do so sensibly – don’t accelerate excessively or brake sharply, don’t speed (the optimal driving speed in fuel efficiency terms in about 60 mph) and don’t have an unused roof-rack or carry unnecessary weight.
If you are buying a new vehicle, choose an efficient one. Driving 12,000 miles a year in a 20 mpg vehicle adds 6.3 tonnes to your carbon footprint. In a 30 mpg one, it adds 4.2 tonnes.
Diesel fuel is better in climate terms than petrol, and its air pollution disadvantages have been reduced. If you have a diesel vehicle, regular engine maintenance is essential.
Hybrid vehicles are an excellent bridging technology, and plug-in hybrids are becoming more widely available. Electric vehicles are better than oil-powered vehicles, whatever the mix of electricity generation. They are already ideal for urban use or for short commutes. Long-range electric vehicles, which can also cope with hills much better than previous electric vehicles, are now available, but are expensive to buy.
A household that uses £500 of electricity and £500 of gas is responsible for about 5 tonnes. If you’re calculating your personal carbon footprint, this should be divided by the number of residents.
There are obvious steps you can take to reduce this and also save money:
- Insulate properly. If you have a loft, make sure it’s well insulated. If you own the property, fit double glazing. Fit draft excluders, which are cheap and easy to install. If you live in a cold country, use curtains instead of (or as well as) blinds. If you live in a hot country, use blinds to keep sunlight out and the temperature down.
- Keep heating or air-conditioning down. 20o centigrade is warm enough, unless you have special need for heat. If you find 20o a bit too chilly, put on a jumper. But if you have air-conditioning on, putting on a jumper is a sign of wastage.
- Wash clothes at 30%. And don’t use a tumble-dryer. If it’s summer and you have a garden, hang the clothes out there. If it’s winter, dry them next to radiators.
- Don’t use electricity on unnecessary activities. Don’t iron clothes more than you need to – saving lives is more important than looking smart. Don’t use a hairdryer – a towel is fine. Or an electric shaver – razor blades do the job better.
Processing and transporting water uses energy. Between 2% and 3% of the UK’s electricity is used for this purpose. This is not yet a major climate issue. Leo Hickman of the Guardian has calculated that “even if you had one very full bath – about 150 litres – every day for a year, overall it would represent just 15 kg of greenhouse gas emissions. That’s about what the average car produces over 80 kilometres.
However, in countries that suffer from freshwater scarcity, water is more climate-significant, as desalination plants are, or will be, used to get freshwater from seawater. Desalination uses a lot of energy. Even the UK could, in the future, have freshwater difficulties. It will get more rain overall, but most of this will probably fall during the winter, with summers being drier than they are today. Therefore, either more reservoirs or desalination plants will have to be built.
The familiar adage ‘reduce, re-use, recycle’ is as important in climate terms as it is in resource conservation terms. Reducing and re-using also saves money:
- Reduce. Don’t accept a plastic bag for shopping if you don’t need it. Take a strong, long-lasting plastic bag, which many supermarkets now sell, or even better, a cloth bag. Don’t waste paper – print on both sides.
- Re-use. Wrapping paper can usually be used several times. (Or newspaper can be used instead, which also conveys a useful climate campaign message.) Clothes should be worn many times, not just a couple of times.
- Recycle. The most important thing to recycle is aluminium, as this is very energy intensive to manufacture. Glass, other metal and paper should also be recycled. However, many counties now collect more goods for recycling than can be used by the recycling industry, partly because consumers are still not buying enough recycled produce. So, for individuals, it is more important now to buy recycled products than to recycle.
If buying timber, you should get it from sustainably-managed forests, not from cleared rainforests. The Forest Stewardship Council is a reliable label (though not perfect) for sustainable timber.
A Japanese study suggests that eating a kilogram of beef causes more greenhouse-gas than driving a car for three hours (see Meat is murder on the environment by Daniele Fanelli http).
You may have been urged to go vegetarian or vegan to help protect the climate. However, different forms of meat have very different climate effects, so this should not simply be a debate between vegetarians and omnivores.
Eating red meat every day would increase your annual carbon footprint by 0.7 tonnes. It would also be bad for your health. Meat from poultry is around a quarter as climate-heavy as beef or sheep meat. Pork, though a red meat, is around a third as climate-heavy. Fish is very carbon-light – though usually bad for biodiversity reasons.
Cows give off methane, which contributes to global warming. A cow produces around 4 tonnes of carbon-equivalent emissions a year, more than the average car and twice the target for global per capita emissions to stabilize the climate.
Organically produced food has a much lower carbon footprint than that produced by intensive agriculture, because of lower emissions and increased carbon sequestration. In fact, a study of 18 Bavarian organic farms found that they had a 26% lower climate footprint.
A Climate Diet should:
- Exclude beef and lamb.
- Include dark rather than milk chocolate.
- Minimise milk and cheese (except feta cheese, which is made from goat’s milk).
- Limit pork/ham/bacon.
- Maximise organic produce.
- Include fish (if desired for nutritional reasons).
And think global, buy local. It is better to buy locally-produced goods than those that have to be transported long distances. Don’t buy anything that has been transported by air.