I mentioned in my previous post the recent kerfuffle about animal agriculture and climate change associated with the work of Gerard Wedderburn-Bisshop (see this podcast and this paper). I also mentioned that I’m kinda done with getting into the details of all these ‘here’s my one weird trick to save the world’ approaches. But various people have asked me to explain further why I find Wedderburn-Bisshop’s position problematic. So … oh well, here goes. See, this is exactly my problem. You’re not helping. (For those on the other hand who’ve already had their fill of this issue, do just skip this post but please come back for my next one, where I’m going to tell a story…)
I’m going to do this quite briefly and summarily, although it’s still quite a long post. I’m not a scientist, but I’ve followed the issues around this for a while and I think I have an okay basic grasp of them. Of course, I’m open to polite criticisms, pushbacks and clarifications. But, as per above, I’m not planning to dwell on this much further (thanks as ever for keeping the comments coming, which is what makes writing these posts worthwhile, but apologies that I don’t always find time to offer adequate replies).
Before I begin let me say that I think much of the global livestock industry is a horror show, and it’d be great to bring the curtain down on a lot of it. Also that cutting down wild forests or ploughing up wild grasslands are terrible ideas. And that there are a lot of good reasons to opt for veganism. That’s not what this is about. There are fewer good reasons to opt for alt-meat, but that’s (mostly) another story.
I have nineteen numbered points, in which I try to navigate what this is about.
1. The main greenhouse gases of importance are carbon dioxide, methane and nitrous oxide. They have different potencies with respect to causing climate change – ‘radiative forcing’ – and different lengths of persistence in the atmosphere.
2. These gases have sources in ‘natural’ (i.e. not human-caused) and biotic processes, and they’re also absorbed and/or chemically changed by other natural/biotic processes (sinks). What’s left at any given time is in the atmosphere, acting as baseline greenhouse gases. But over the short-term on human timescales the natural carbon and nitrogen cycles are quite stable and the climate doesn’t change much as a result of them.
3. However, modern human activities add in a lot more of these gases to the mix by either adding to the sources or subtracting from the sinks, hence potentially changing the climate. The major relevant activities that do this are (1) burning fossil fuels, producing carbon dioxide and methane from carbon that was laid down geologically from previous epochs (2) land use change, particularly deforestation and agricultural cropping (3) methane emissions from ruminant livestock (and also from rice cultivation) (4) nitrous oxide emissions, mainly from agricultural fertilisers (5) carbon dioxide emissions from cement manufacture.
4. Activities 2-5 can be undertaken without using fossil fuels, but in the contemporary world they’re largely fossil fuel dependent and downstream of fossil fuel use – it wouldn’t be possible to do them at present speeds and scales without the contemporary abundance of cheap fossil energy. Therefore, there are conceptual difficulties with claims like “animal agriculture (or whatever) causes more climate change than fossil fuels”. Directly or indirectly, there’s a fossil fingerprint behind most contemporary climate change.
5. Because fossil fuel combustion involves putting new carbon (in the form of carbon dioxide and methane) into the atmosphere that was previously stably sequestered in the Earth, with almost no sinks in the fossil fuel sector itself, the gross amount added from combustion provides the relevant measure of carbon flux from the sector. Whereas in the case of land use change there are both sources of carbon (e.g. deforestation) and sinks (e.g. afforestation). Wedderburn-Bisshop’s main argument is that we should not use a net measure for LUC and a gross one for fossil fuels, but this doesn’t make sense from the point of view of accounting accurately for the overall carbon balance.
6. The different atmospheric persistence of GHGs means there is no one single ‘correct’ way to combine them into an overall measure for the radiative forcing of current GHG fluxes – the time period under consideration matters. If we consider the immediate forcing right now, then methane – which has potent radiative forcing effects but low persistence – looms relatively larger, whereas if we consider forcing over long time periods its impact diminishes relative to carbon dioxide, which has longer persistence.
7. Anti animal agriculture activists often emphasise the benefits of cutting methane – for example, in this piece, which states “Cutting methane emissions represents a near-term opportunity for meaningful climate relief”. A lot turns on the word ‘meaningful’ in that sentence. If we cut out all ruminant livestock, then that would potentially reduce atmospheric methane and create some short-term climate relief. But if we did so without cutting fossil fuels, that short-term relief would not prove ‘meaningful’ in the long-term because it would be very much more than offset by ongoing carbon dioxide emissions from fossil fuels. Moreover, fossil fuel combustion also involves methane emissions of roughly the same magnitude as methane emissions from ruminant livestock. If we were going all out for climate relief, then it might be meaningful to cut out ruminant livestock at the same time as cutting out fossil fuels. It seems harder to argue that cutting the former without cutting the latter is meaningful, except as a short-term palliative whose positive impact is soon lost. The analogy I’ve used before is pouring a bucket of cold water over yourself if you’re sat in the midst of a raging house fire – possibly worth doing if you then immediately do something about the fire, but otherwise not. So, yes, if you opt for only an immediate/near-term perspective, the methane emissions from ruminant livestock loom larger as a concern (so do the methane emissions from fossil fuels), but this isn’t a particularly sensible thing to opt for. It may even be less than useless, if people take a ‘job done on climate’ attitude toward quitting their meat consumption.
8. There are different metrics for comparing the longer-term impact of the various greenhouse gases, such as GWP and GWP*. I’m not going to get too far into them here. GWP* is often criticised by anti animal agriculture folk (including Wedderburn-Bisshop) as somehow a contrivance of the animal agriculture lobby. I even saw it described recently as ‘manipulative’. Well, there are lots of accusations of bad faith flying around in this debate, but I’d like the people making these kinds of claims to look at the work of Myles Allen, Michelle Cain and others who developed the metric (like here, for example) and explain exactly what they got wrong or what’s manipulative about it.
If we assume that GHG sinks at worst stay constant (Wedderburn-Bisshop certainly does assume this), then the short persistence of methane means that the methane emitted from a constant existing number of ruminants doesn’t have much forcing effect because of its rapid removal by the sinks. If more livestock are added, it will have a heating effect. If livestock are removed, it will have a cooling effect. I don’t think this is especially controversial: constant ruminant livestock, little forcing, other things being equal.
Far from being ‘manipulative’, I’d say the implications of GWP* align pretty well with a sensible climate change mitigation strategy consistent with reducing the most problematic forms of livestock from a climate change perspective – viz. (1) focus on cutting fossil fuel use (which will likely result in less livestock) (2) try to augment and absolutely don’t compromise existing GHG sinks (hence, no deforestation or ploughing for livestock) (3) where appropriate, cut ruminant numbers (but keep carbon dioxide reduction front and centre of attention).
9. In his Planet Critical podcast, Wedderburn-Bisshop made quite a play for the ability of existing sinks – especially forests – to deal with fossil fuel emissions. This seems to me unwise. A forest is a much less stable form of carbon sequestration than an underground coal seam or oilfield, and we cannot expect existing biotic systems to endlessly absorb additional fossil carbon accumulated over millennia. Sinks may eventually become sources. Hence the key importance of leaving fossil fuels in the ground. Generally, I found Wedderburn-Bisshop to be worryingly relaxed about the key importance of fossil fuel emissions in respect of climate change and overly focused on livestock.
10. One reason afforestation may not be a stable form of carbon sequestration is because of wildfires, which are a major consumer of woody plants in many parts of the world. Promoting carbon sequestration through afforestation in these fire ecosystems is unlikely to work, because the woodland sink easily becomes a combusted source. Wedderburn-Bisshop doesn’t pay much attention to woodland-grassland-fire-ruminant relationships. But not every ecosystem is substantially wooded and in some ecosystems grass-ruminant relationships may select better for carbon retention or sequestration. When I said in Point 7 that cutting ruminant numbers may only ‘potentially’ create climate relief, that’s one of the reasons.
11. More generally, I find it unclear from Wedderburn-Bisshop’s paper how he construes the relationship between deforestation and animal agriculture. Not all deforestation is agriculturally related, and of that part of it that is it can be hard to allocate out the proportion that relates to animal and non-animal agriculture (e.g. with soy production). Nevertheless, animal agriculture does play a role in it and Wedderburn-Bisshop is right that deforestation for animal agriculture can’t be justified on climate change grounds – not that this is a novel or especially controversial position.
12. As previously argued in (10), not all animal agriculture occurs in places that would otherwise be forested. But some of it does. Here in Britain, for example, while the extent of original wildwood forest cover is a matter of debate, there’s unquestionably a good deal of ruminant husbandry on agricultural grassland that would be wooded in the absence of ruminants. This prompts the so-called ‘carbon opportunity cost’ argument in respect of reforesting previously cleared agricultural grasslands in places like Britain where consumption of woodland by wildfires is not – yet – a major problem. An underemphasized difficulty with this argument is that afforestation only works as a carbon sink for a limited period (in the order of decades) before it becomes essentially carbon neutral. This returns us to point (7) – in the long term, afforestation is only ‘meaningful’ as a climate relief measure if accompanied by reductions in fossil fuel combustion.
13. The relationship between livestock, afforestation and human ecology is often complex in any given locale and can’t necessarily be reduced to a simplistic ‘cut livestock’ agenda. For example, Wedderburn-Bisshop mentions in the podcast the issue of deforestation caused by sheep in Scotland. There is undoubtedly some historical truth to this, although the problem of ruminant browsing was largely a side-effect of the problem of human political power. The fact that sheep caused deforestation in Scotland does not mean that all deforestation in Scotland was caused by sheep, nor that all forms of sheep-keeping inevitably cause deforestation. Anyway, the main contemporary agent of deforestation in the Scottish Highlands is not sheep, but deer. Deer are ‘wild’ but are managed for commercial trophy hunting by large estate owners (human political power again). If you want to reforest the Highlands today, that basically means you have to kill a lot of deer – especially female deer, which are not highly valued by trophy hunters, but that produce the males which are. But this culling runs counter to the inclinations of the hunting estates – perhaps also to those of many anti animal agricultural activists?
I took the photo above in the Scottish Highlands. In the centre left of the picture you can see some afforestation, which relates to small-scale landownership by crofters, some of whom keep ruminant livestock. There is little afforestation in most of the rest of the picture, which relates to large-scale landownership where there is little livestock, but a lot of deer. In this region, afforestation could be better achieved by policies to widen access to landownership and to kill wild animals (deer) than by cutting ruminant livestock or popularising veganism. There are also questions in this biome about whether afforestation is the best strategy for improving carbon sinks. Restoring and preserving peat wetlands is sometimes a better bet, while afforestation is sometimes counterproductive. All of which is to say that afforestation can be socially and ecologically complex, and not necessarily reducible to banning ruminant livestock – a policy that often deleteriously affects small-scale pastoralists whose activities have minimal or even mitigating effects on radiative forcing. It would be good if we stopped thinking of trees as no more than carbon angels and ruminant livestock as no more than carbon devils, and started getting busier with local detail. We need to go beyond ‘trees good, ruminants bad’.
14. In the podcast, Wedderburn-Bisshop says that deforestation will stop if people stop eating meat, because “they won’t clear for clearing’s sake, they only clear to produce beef”. I think this misunderstands the nature of capitalist agriculture, particularly on extensive (neo-colonial) frontiers. Pressing the logic further, we could say “they don’t produce beef for producing beef’s sake, they only produce beef to produce profit”. If, due to regulation of livestock production or changing consumer preferences, it was no longer profitable to produce beef, then the likelihood is they would produce something else on these deforested extensive frontiers that generated a better profit, most likely also with deleterious effects upon climate, biodiversity and people, especially local people. Feedstock crops for biofuels, bioplastics or other industrial products, and for processed human foods like alt-meat spring to mind.
15. One of the best ways to mitigate against this is to allocate land in small parcels to people who are going to use it produce food and other necessities for themselves locally. I don’t think there’s any mention of this on the website of Wedderburn-Bisshop’s organisation. Why not? Instead, there’s a lot of stuff about corporate investment in alt-meat. If it’s true that people don’t need to eat any meat or dairy products, it’s also true that they don’t need to eat any alt-meat or alt-dairy products. Generally, changing property rights to improve access to land for small-scale farmers is a better way to restore ecosystems than changing consumer choices in capitalist markets wedded to high-energy supply chains like those associated with alt-meat.
16. Just to press that a bit further, I think the debate about livestock often errs in imputing to animal agriculture what’s really a problem of overproduction of arable grains. The big growth story in global animal agriculture isn’t ruminants but chicken and pork, and this in turn is about adding value to arable overproduction of cereals and grain legumes, often from extensive frontiers. As just mentioned, there are other, non-animal ag ways of doing this that are also destructive. It’s a bit simplistic, I know, but basically I think we need to distribute land and let people get on with producing food, energy, fibre and fertility from it for themselves. If we do that, we’ll find that at least in the more densely populated places there won’t be an awful lot of livestock – but there will be some, and its impact will be slight.
17. I haven’t said anything yet about the nitrogen cycle in this post, but the human augmentation of it in agricultural systems has been catastrophic for wildlife. Nitrogenous fertiliser is hard to come by in low-energy peasant food systems, which in this respect are much less ecocidal than modern high-energy, high-nitrogen capitalist food systems, livestock-based or otherwise. One of the main ways that people manage farm fertility in low-energy food systems is by using livestock as vectors for it. We need to stop thinking of livestock as just sources of meat or dairy products – or, even worse, as ‘protein’ – and start thinking of them as ecological protagonists in low-energy (non fossil fuel) local food systems.
18. Much as I’m sympathetic in general to messaging along the lines of ‘let nature take its course’, rather than assuming that human meddling will do a better job, unfortunately I don’t think we can just let nature take its course to right the wrongs of our historic human meddling with the global climate. This means (1) leaving fossil fuels in the ground (2) carefully preserving and augmenting carbon sinks (3) fitting farming and human activities carefully to local ecologies, which probably means reducing livestock in the farming systems of a lot of places – but not all livestock in all farming systems in all places. As I see it, Wedderburn-Bisshop’s intervention only relates to one aspect of (3), and is therefore inadequate at best.
19. Finally, I’ve read quite a bit of stuff online that speaks up for Wedderburn-Bisshop’s paper on the basis of meta claims about the conservatism of science in general, the conservatism of government-validated IPCC science in particular, and the virtues of having challenging new voices in the debate. All these things are true enough in general, but challenging new voices do have to exhibit some baseline intellectual plausibility, or else they won’t dent the existing scientific consensus, which is conservative for a reason. Too many of us in the wider world get the wool pulled over our eyes by ‘disruptive’ voices in deep conformity to what we wish to believe rather than what’s actually true. As in the case of alt-meat and alt-dairy, these ‘disruptive’ voices are often also in deep conformity to business-as-usual ways of doing things, such as using high-energy industrial approaches funded by venture capital seeking high returns.
Teaser image credit: Highland wood and moor. Author supplied.