To eat meat, or not to eat meat: this is an immensely controversial and topical issue at the moment and linked in with both personal health and the health of our home planet. I wanted to know if giving up my beloved meat would be the most effective way for me to drop my carbon footprint and take another step forward in being a responsible human.
There are two ways in which we create greenhouse gasses. First, those fossil fuels we directly use up when we use gas and electricity to heat and power our homes, when we drive around using petrol or diesel, and when we fly. Second, we indirectly contribute to greenhouse gas emissions through energy that’s “embedded” in the things we do an the things we buy, like leather.
Leather itself comes with its own “embedded” greenhouse gas emissions from the farming and meat industries, in addition to the carbon footprint of actually tanning the materials. This is because without people like me who eat meat, then there wouldn’t be any hides or skins to tan (or to landfill.)
Greenhouse Gas Nerd
I live and work with someone who is rapidly becoming a greenhouse gas nerd, and who randomly and spontaneously exhumes vital snippets of information, without which my life would be incomplete.
These life changing factoids include:
“The main source of atmospheric nitrous oxide – a greenhouse gas more than 250 times more powerful than carbon dioxide – is agriculture.”
Followed by a mini thesis on whether the true cause of global warming is all the farming that we’re doing to keep the vegans fed….
And then there are the genuinely useful snippets. Like the ones that make me realise that although I know a bit about the main greenhouse gasses (carbon dioxide, nitrous oxide, methane, and those carbon-fluoro-compound thingies), I don’t know it all. I hadn’t appreciated that they a) don’t stick around in those chemical structures forever, and b) the rate at which they react with other chemicals around them to form other – non greenhouse gas – chemicals are varied. Ultimately this means that it’s complicated, and a simple table isn’t going to be able to work.
That didn’t stop me from trying, though.
A Simple Greenhouse Gas Table
The first “draft” of my table got me ranting and pulling my hair out: how are us mere citizens of the world supposed to make sense of all of the variations on the “truth” about global warming if we can’t even get access to the basic data. How on earth am I supposed to find out how long carbon dioxide sticks around in comparison to methane or nitrous oxide?!
In my frustration, I admit that I may have grumbled at my greenhouse gas nerd, with the not-so-subtle inference that this lack of clearly accessible data was all his fault. Within seconds, I had a shiny, sparkly link to the Carbon Dioxide Information Analysis Centre, with a page all about “Recent Greenhouse Gas Concentrations.”
Maybe I should grumble at my tame greenhouse gas nerd more often….
And so I learned, that a table is actually possible, and it looks something like this:
Oops. So now it’s really clear why there was such a hoo-ha about CFCs not so many years ago. And it also looks like nitrous oxide is a serious baddie when compared with carbon dioxide. Then I looked at the atmospheric concentrations: carbon dioxide is measured in parts per million, and methane and nitrous oxide are measured in parts per billion. Just to be clear, we’re talking about American millions (1,000 million), not the old-school British million-million version of billions.
So, my table now gets a level-up, and now looks something like this:
So now I need to take into account that while methane and nitrous oxide are present in low concentrations compared to carbon dioxide, they have a significantly higher global warming potential, so their impact on the globe needs to be worked out.
In the end, with my little friend Excel, I came up with this:
What it shows is that the absolute concentrations of methane and nitrous oxide are miniscule compared to that of carbon dioxide in the atmosphere (blue), but when you take into account their global warming potential, it’s not insignificant anymore (grey).
The global warming potential of the current concentrations of nitrous oxide in the atmosphere is about ¼ that of carbon dioxide, and the combined global warming potential of nitrous oxide and methane is about 1/3 that of carbon dioxide.
So that’s why carbon dioxide is still the bad guy (now that CFCs are mostly under control) – simply because of sheer volume.
Is veganism the answer to global warming?
With all the fuss in the press about the carbon impact of being a meat-eater, and the very active campaign to persuade us all that veganism is the modern version of Jane Fonda, I wanted to know if ditching meat is the most sustainable decision I can make right now.
I found some greenhouse gas calculators (because I’m not the residential greenhouse gas nerd…) and plugged in our family activities. To keep it simple, I kept to just our home and – on purpose – left out the business stuff like flying to meet clients or running and incubator for 6 months to find out if leather can be composted in a sustainable manner.
According to carbonindependant.org, if I went from my current “average” meat and dairy consumption to a full vegan diet, I’d save 0.4 tonnes of carbon dioxide each year.
Okay, so that’s not insignificant. Does that mean I need to seriously think about going vegan? Then I noticed that I can achieve the same effect by changing my shopping from buying “some” organic food to “all” organic food (0.5t/yr). Alternatively, I can achieve a 0.4t/yr carbon saving by a combination of: changing my “average” local food purchases to “mostly local”; and moving from “average” packaged food to “below average” packaged food.
Finally, if I really don’t feel like putting more than my weekly two minutes into buying food, I can replace 1,500 miles of car travel with a train or bus journey to achieve a saving of 0.43 tonnes of carbon dioxide per year. Hmm….
In the interests of scientific robustness (or perhaps merely confusing myself further), I skipped over to carbonfootprint.com to try out their calculator. Firstly, they don’t ask lifestyle questions (do you recycle?), but instead ask how much money you spend on food etc, on order to work out your “embedded” carbon impact.
After a bit of mathematical gymnastics to make sure I got the numbers right, I ended up with a result that showed me that if I spend £500 less each year on food, or paid off my mortgage, so that I pay less in instalments each month, then I’d achieve the same carbon savings as going vegan (0.4 tonnes of carbon each year.)
And I think that just might be one of my biggest reservations with any argument that claims that an all-or-nothing approach to something will save the planet. The way in which our activities impact global warming is an incredibly complex web of interwoven elements. As with so many things trying to distill it into simple solutions skews the results beyond common sense; a balanced approach may be more sustainable.
Many of us can remember when eggs were considered evil incarnate for anyone who looked like they might have high cholesterol, and now they’re considered a superfood; one of the most nutritionally dense and healthy foods we can eat. The same thing has happened with saturated fats (not that it’s a superfood, though), and even MSG might not be quite so nasty as we were originally told.
As so typically happens in my life, it was only as I was getting to the end of writing that my not-so-tame greenhouse gas nerd handed me a pretty picture that – had I known about it three hours earlier – would have altered the course of my afternoon.
It would appear that my lifestyle choices are infinitely sustainable, and that I have already saved more carbon emissions than seventy vegans, linked arm-in-arm, singing Kumbaya together could achieve.
I might celebrate with a fine steak this evening.