- Agriculture and land use account for around 26% of global greenhouse gas emissions
- Cattle ranching is the largest contributor to tropical deforestation
- Unsanitary conditions common in industrialised animal farming allow diseases to multiply and mutate
When asked to consider the factors driving the climate crisis, most people wouldn’t immediately think of agriculture. This is regrettable for two reasons. Agriculture and land use account for around 26% of global greenhouse gas emissions, second only to the energy sector. This includes emissions from livestock, crop production, land use, including deforestation, and the supply chain.
Also, according to research by Project Drawdown, which ranks the most economical climate solutions for mitigating warming to 1.5⁰C above pre-industrial levels, 14 of the top 25 most cost-effective solutions are related to sustainable agriculture and land-use change. These include reducing food waste, switching to plant-rich diets and tropical forest reforestation. Many of these changes will have positive social and environmental co-benefits, such as the health benefits of transitioning to a more plant-based diet.
A healthy and sustainable global food system is essential for providing decent sustenance to a global population that is expected to reach 9.7 billion by 2050. The agriculture sector is also a critical component of the global economy, accounting for around 3.9% of global GDP. However, the way in which we produce food is creating negative social and environmental outcomes. Many of these impacts relate closely to themes within our engagement programme.
Animal agriculture plays an outsized role when it comes to contributing to the climate crisis, as well as other environmental and social issues, with 31% of food-related emissions coming from livestock and fisheries. Yet only 7.6% of caloric supply comes from animal protein. Methane, a greenhouse gas with a global warming potential 28 times greater than carbon dioxide over a 100-year timeframe, is a significant contributor to agricultural emissions. It is produced by ruminant livestock, such as cattle and sheep, through natural digestive processes known as ‘enteric fermentation’. Cattle are the largest contributors to agricultural emissions, with lifecycle emissions of around 5 gigatonnes of CO2e (6%) annually. This is more than half of all livestock-related emissions and around three times greater than aviation emissions. Meanwhile, commodity-driven deforestation accounts for around 5% of global emissions. Here again, cattle ranching is the largest contributor to tropical deforestation, followed by land clearance for palm oil, maize, rice and soy crops.
Continued deforestation is not only a concern for the climate, as forests absorb around 7.6 billion tonnes of carbon dioxide per annum, but also for ecosystems and the services that they provide. Services such as air purification, erosion control, temperature regulation and the provision of livelihoods for indigenous communities and others, are critical but they are difficult to value, although some estimate their worth at around $150tn. Forests provide a habitat for 75% of bird species and 68% of all mammal species. This high level of biodiversity is critical for maintaining the integrity of these ecosystems and their continued provision.
The encroachment of agriculture into pristine landscapes through deforestation or other land-use change creates a wide range of social harms, including human rights impacts on indigenous people and the increased risks of zoonotic diseases. The unsanitary conditions common in industrialised animal farming, coupled with the overcrowding of animals, which weakens their immune systems, allow diseases to multiply and mutate.
The intensive nature of current animal farming practices, which provide the vast majority of animal protein, have adverse consequences for local environments and ecosystems. These include impacts on human health related to noxious gases and the pollution of other aquatic systems, often impacting less affluent communities more severely. Some 78% of global eutrophication, the process of pollution through excessive nutrient runoff, is caused by the agricultural system, with cattle rearing having the highest impact. The impacts from eutrophication are likely to get worse due to climate change and overfishing.
However, it is not only the rearing of animals, and the acute need to shift towards a plant-based diet, that we need to consider. Poor health and nutrition are driving higher rates of obesity. In the UK, this costs the economy £54bn annually, including £6.1bn of costs for the NHS.
The pandemic has also highlighted the food system’s dependence on migrant labour, where human rights violations are more common. Additionally, it has revealed direct human capital risks, such as the conditions within meatpacking factories, where incidents of Covid-19 in the US have been far higher than the national average. This demonstrates the need for companies to take greater responsibility for the health, safety and wellbeing of their employees.
In the next article in this series, we will explore the ways in which the food system is dependent on nature. The sustainability of ecosystem services is critical for the long-term future of the sector. For example, there is nothing that the food system is more dependent on than soil, and in the US, around 40-60% of organic matter has been lost over the past century. Continued compaction, tilling and soil loss pose an impending crisis for the sector and society at large.