The five commandments of climate change

Climate change is a huge problem. Often people feel so overwhelmed that they don’t know what to do. And there just seems to be so much noise around what we should be doing. So, I have been thinking about how we might distil this down to a handful of imperatives, i.e. the five commandments of climate change. Unlike the better-known ten commandments, these would require just one stone tablet. However, my thinking is not sufficiently advanced to call the stone tablet carver just yet.

If you are a tourism operator, it might be worth thinking about these commandments and advertising to your clients the extent to which you are adhering to them. It could go a long way to establishing your climate credentials. Here they are and I would be interested in your feedback on them (greg@bodekerscientific.com).

The first commandment

Don’t take carbon atoms out of the ground and put them into the atmosphere.

I like thinking about atoms - please indulge me for a few sentences… I once asked my daughter how old she was. She said she was seven years old. I then pointed out that the atoms in her body were all created in the sun around 3.5 billion years ago and that since she consists of nothing but atoms, surely she is then 3.5 billion years old? I think that was the first time I heard her say to her brother (who is 3 years older), “Dad’s weird”. It wasn’t the last.

Back to the point: Carbon atoms are found in molecules such as carbon dioxide (CO₂) and methane (CH₄) – I have marked them in bold. When you burn coal or oil, the carbon contained therein combines with oxygen in the air to create CO₂. Earth cools itself by emitting infra-red radiation. CO₂ is very efficient at absorbing that radiation and re-emitting it, with around half of that emission coming back down to Earth and warming it. This is the greenhouse effect, with CO₂ being a strong greenhouse gas. But what of the C atoms in the oil that came out of the ground used to make my skellerup gumboots? Not nearly as bad since it didn’t result in the carbon atoms going into the atmosphere. They’re stuck there in my gumboots. Taking oil and coal out of the ground is a little bad (because CH₄ is released into the atmosphere when you do that), but whatever you do, don’t then go and burn it! Unfortunately, that means that you can’t drive a petrol or diesel power car or burn coal, e.g. to make steel.

The second commandment

Do like your mum said – if you take carbon atoms out of the ground, be sure to put them back.

If you can’t avoid breaking the first commandment, and there are several cases when you simply can’t help it, obey the second commandment. Offset your emissions, e.g. through tree-planting programmes but make very sure that those programmes are robust and that the forests in which those trees are grown are permanent, i.e. permanently remove the carbon atoms from the atmosphere.

Direct air capture technologies are also in development where CO₂ is directly captured from the air, liquified and then pumped into disused mines or geological faults, but these are not yet commercially viable.

The third commandment

Don’t put gases into the atmosphere that are good at absorbing infrared radiation.

This recognises that carbon dioxide and methane are not the only greenhouse gases. There are several others, some of which don’t contain carbon atoms (e.g. nitrous oxide (N₂O)). Some are replacements for chemicals that cause depletion of the ozone layer (a scientific problem I worked on for 20 years).

To allow different gases to be compared for their propensity to warm the climate, a measure called the global warming potential (GWP) was developed. The GWP describes how much more (or less) a 1kg emission of that gas will lead to global warming over a 100-year period compared to a 1kg emission of CO₂.

Methane has a GWP of around 30. CFC-13, a gas that is a strong destroyer of ozone, has a GWP of 13,900; as a result, the Montreal Protocol that banned many ozone depleting gases (including CFC-13) helped reduce global warming by those gases. Some of the hydrofluorocarbons developed to replace gases that destroy ozone still have high GWPs (e.g. 12,400 for HFC-23).

The fourth commandment

Don’t convert some gas in the atmosphere to a different gas that is a stronger greenhouse gas.

This is a big one for New Zealand because this is where cows and sheep make their appearance. Many people argue that methane emissions from cows and sheep shouldn’t be included in greenhouse gas emissions budgets (and in any associated taxes) because it is all part of a natural cycle. And, to some extent, they’re right. Cow and sheep farming certainly doesn’t break the first commandment (and so the second doesn’t apply). Let’s think about atoms again. When a cow burps out a molecule of CH₄, where did that C atom come from? It came from the grass the cow ate a couple days earlier. And the C in the grass came from a CO₂ molecule in the atmosphere – a CO₂ molecule got converted into a CH₄ molecule. But now comes the annoying bit. That CH₄ molecule is 30 times more potent as a greenhouse gas compared to the CO₂ molecule it got made from (see the GWP above). So those cows, in addition to producing delicious milk and yummy steaks, are also ‘machines’ that convert a relatively weak greenhouse gas (CO₂ – although if you put enough of it into the atmosphere, as we have, it still has a huge impact on the climate) into a much stronger greenhouse gas (CH₄). The carbon in the CH₄ molecule in the atmosphere, over around 10 years, gets converted back into a CO₂ molecule (the natural cycle) but, while the C atom is in the form of a CH₄ molecule, it has a much bigger effect on the climate than if the C atom has stayed as a CO₂ molecule. So, I really should become a vegetarian but, so far, I have resisted because steaks taste so good. Mea culpa.

The fifth commandment

Don’t engage in activities that would cause others to break commandments one to four.

This gets tricky. I ride my bike to work and back every day as part of my weight-loss programme. It doesn’t work. Admittedly it’s 194 metres door-to-door and takes 35 seconds (45 if there’s traffic). I got into the habit of cycling to avoid using a petrol-powered car as much as possible. But looking at my bike, I see how much of it is made of steel. The production of that steel almost certainly required the use of fossil fuels and so, in buying my bike, I caused someone else to break the first commandment. Furthermore, I am quite sure it was transported on a diesel-powered truck from the factory where it was manufactured to Henderson Cycles in Alexandra where I bought. There goes the first commandment again. But what if the steel was created in a ‘carbon zero’ mill? What if the truck that transported it was battery powered? Ah, but maybe the person who owns the steel mill used the profits from the mill to fly with his/her family to some exotic holiday destination. Me buying my bike added to those profits, enabling him/her, in part, to fly around the world emitting greenhouse gases. Should I have enquired about the holiday habits of the owner of the mill before I bought my bike? You can do this sort of thinking forever. One day, when the ‘externalities’ of climate change have all been priced correctly into products and services, the market will take care of this. Until then, for this commandment, all I can say is that if you have several options, choose the one that will ultimately lead to minimising greenhouse gas emissions somewhere down the rabbit hole where such thinking takes you.

Conclusion

This is where I have got to with crafting my five climate change commandments. Are they useful? Do they help in terms of how to think about mitigating climate change? Are they too obscure? Please let me know what you think. And please let me know what, specifically, you would like me to write about (I did get one suggestion from my November piece and will get onto that soon).