Eastern European diaries: the question of meat

In the Balkans, where my family roots are, we eat a lot of meat. I've always enjoyed eating lots of meat and joked that it's all part of my cultural heritage: I wouldn't be a true Eastern European if I didn't eat it! However, the "Global Warming" course I'm taking at the moment has seriously made me reconsider my meat intake to the point that I have decided I seriously need to reduce it. Here's why...

Firstly, we all know the that cows produce methane when they fart. Why is methane so bad? Well:

1. methane is a greenhouse gas meaning it traps incoming solar radiation. A molecule of methane traps 25x the heat a molecule of CO2 does.
2. methane reacts with OH in the atmosphere which means HCFCs and HFCs (2 greenhouse gases with heat trapping abilities 1000s more times potent than that of CO2 or methane) last longer in the atmosphere because the only way to break down HCFCs and HFCs is through reaction with OH which increased methane depletes the concentrations of.
3. methane reacts with nitrous oxide (using energy from the sun) to produce ozone (another greenhouse gas).
4. some methane makes it into the stratosphere where it is oxidised to become H2O. H2O in the stratosphere is an especially strong heat trapper.

So methane is bad news. In terms of animals, cattle are the worst, with dairy cattle emitting 88kg per animal per year; beef cattle emitting 55kg per animal per year; sheep emitting 8kg, and pigs 1.5 kg, again per animal per year. Even though cows are significantly larger than sheep and pigs, one (beef) cow will still produce more methane than the number of sheep or pigs equivalent to the one cow's mass.

Estimated methane emissions per animal per year.
Picture sources: cow= The Guardian; sheep= Wikipedia; pig= animal-dream.com

Looking at overall greenhouse gas emissions from animal products in the bar graph below also reveals beef as the worst offender, with beef emitting 4 times the greenhouse gases than pork or chicken. Beef production emits lots of greenhouse gases because of the fossil fuels used for example to make the fertilisers to grow animal fodder; the enteric fermentation (cows farting); methane from manure; and nitrous oxide from manure (bear in mind that nitrous oxide is another greenhouse gas where one nitrous oxide molecule has 206x the heat trapping ability of one CO2 molecule). So this graph seems to suggest I should cut down on beef and sheep intake and if eating meat at all, should either eat pork or poultry.

Greenhouse gas emissions per MJ of food energy.
Source: Danny Harvey. 

The graph above also shows that, comparatively, eggs and dairy do not have as high greenhouse gas emissions, so it should be fine to keep drinking milk, right? Well, the next graph shows that compared to other drinks, milk production emits significantly more greenhouse gases per litre than any other drink. As such, I would do well to look into milk alternatives such as soy milk.

Greenhouse gas emissions per litre of beverage.
Source: Danny Harvey.

It's also important to consider the land needed to support these animals. There is almost 2.5 times as much pastureland as cropland in the world, and around half of this cropland is devoted to producing food for animals rather than to directly producing food for humans. Overall, the energy flows from crops (often corn) fed to the animals (including the inedible byproducts of the cropland) to the animal and then to the human consumer reveal an incredibly low efficiency of only 4%. Given meat consumption per capita is increasing globally and the human population is also growing, more and more land is being cleared (often deforested) for animal pasture and for producing the crops for the animals to feed on. With global warming expected to reduce agricultural yields, the rising demand for meat is worrying as we would need even more land to keep up with demand: in fact, decreases in agricultural yields due to adverse climatic changes could be fully offset by rather modest reductions in meat consumption. 

Overall, this (British-)Eastern European is going to aim to reduce her intake of meat, especially methane-heavy beef. I will also try to cut down on my dairy intake (even though it will significantly impact my hot chocolate habits) and most simply of all, I will try to reduce my food waste. My Slavic identity has always partly found expression in the food culture that emphasizes meat, but even though I now plan to eat less meat, I'm sure I can express my Slavic side in other ways that won't impact the environment so much.