It is always surprising how little animal agriculture is discussed among environmentalists,
especially because it is widely recognised as one of the key drivers of climate change. Even the most conservative estimate from the World Resources Institute holds that animal agriculture is responsible for 14% of all human-caused greenhouse emissions, with the United Nations Food and Agricultural Organisation estimating as high at 18%.

According to even the lowest of these estimates, animal agriculture may account for more greenhouse emissions than the combined total of every car, truck, train, aeroplane, and ship on the planet. The impact of animal product consumption on emissions is so significant, that if everyone in the US went one day a week without eating meat or cheese, it would be the emissions reduction equivalent of taking 7.6 million cars off the road. It can be hard to recognise precisely where all of these emissions are coming from, but the sheer scale of animal agriculture is often underestimated by environmentalists.

We don’t have exact numbers for how many animals are killed per year (an unsettling fact in and of itself) but it is estimated that more than 70 billion animals are slaughtered each year, not including fish, whose lives are measured in tonnes. Raising, feeding, and providing grazing land for these billions of animals is extremely resource-intensive, and every stage of production comes with significant environmental problems.

Animals produce methane as a result of their natural digestion, and methane has a global warming potential of around 86 times that of CO2, over a 20-year time frame. Add transport, fuel, and crop production emissions, and it is not difficult to see exactly where all this destruction is coming from. On top of emissions, farmed animals produce an enormous amount of waste, all of which has to be managed and disposed of. The US Department of Agriculture estimates that farmed animals generate more than 450 million tonnes of manure annually. That is three times more raw waste than is generated by all Americans combined. This human waste is subject to filtering and cleaning systems, whereas animal waste is usually stored in gigantic lagoons and then used, untreated, to fertilise crops. This leads to many documented health issues and is responsible for most of those high profile E-coli outbreaks we hear so much about.

This waste makes its way into local waterways and streams, polluting them severely, as has been demonstrated in dozens of independent studies. This is especially problematic in flood-prone areas, which causes untold damage to human health, homes, and waterways. Despite this, large livestock farms still go largely unscrutinised by government bodies. Of course, it is not just our environment being damaged by animal agriculture; we share it with millions of other species which we are driving to extinction with our actions. Animal agriculture plays a prominent role in this extinction, with the World Wildlife Fund’s 2017 report stating that meat-based diets are responsible for an alarming rate of biodiversity loss.

This is due to a combination of factors – the most significant of which is the vast
swathes of land required to produce enough animal feed to accommodate our appetite for animal products, with a full one-third of the planet’s arable land surface devoted to animal agriculture. This massive land requirement is only expanding, with more wildlife habitat being destroyed to provide new grazing and farming land every day. It is estimated that animal agriculture is the direct driver of around 80% of deforestation worldwide, with untold consequences for the wild animals who used to inhabit these fragile and incredibly diverse ecosystems. It is not just domesticated animals whose deaths are caused by our appetite for animal products then, but millions of wild animals, too.

What we must conclude from this is as clear as the message from just about every
authoritative organisation on climate change: we simply cannot effectively combat climate change without addressing the problem of animal agriculture. It is polluting our air and our water, it is laying waste to our forests and decimating ecosystems the world over. Of course, other significant sources of emissions must be reduced, including the largest factor, which is thought to be heat and electricity generation.

Veganism will not solve the environmental crisis alone, but going vegan is something
practical that every one of us can do to significantly reduce our carbon footprint on earth, without having to live off-grid, or even make any radical changes to our standard of living. Veganism is one of the most impactful ways to reduce our environmental impact. That is why even the UN has urged a global move towards plant-based eating. Given the extent of our current climate crisis, it is something that every committed environmentalist should be working towards.