An incredible 60% of all non-human mammals on earth are ‘livestock’ animals in our food system (with humans making up 36% and ‘wild’ animals 4%); for birdlife, 70% are those within the food system such as chickens, and 30% are free living. We have known about the climate impact of ‘livestock’ since at least 2006 and it is now widely recognised that, globally: 

• The food system is responsible for around a quarter of all direct greenhouse gases;
• ‘Cattle’ alone are responsible for nearly a tenth of all direct greenhouse gas emissions – 6% from beef and 3% from dairy;
• ‘Beef’ from cattle is responsible for a quarter of the entire food system’s emissions, despite providing only 1% of global calories; 
• While using ~83% of the world’s farmland, ‘livestock’ products contribute only 18% of global calories.

While there are many additional environmental challenges in the production of food, plant-based food system has been shown to have significantly less environmental impact than ne based heavily on farming animals. And the UK is part of that global food system, with its own footprint: 

• The UK agriculture sector is responsible for nearly one tenth (46 MtCO2e - million tonnes of carbon dioxide equivalent - in 2017) of the UK’s greenhouse gas emissions, much of which comes from farming cattle and sheep. The Committee On Climate Change’s Land Use Policies for a Net Zero UK report specifically targeted ‘low-cost, low-regret’ shifts to increasing plant-based options to replace beef, dairy and lamb consumption (their report suggests a 20% per capita reduction of these ‘meats’; we are more ambitious in our desire for the UK to show global leadership in taking its ‘fair share’ of climate reduction activities, which we believe would be best done by pioneering a fully plant-based transition).
• The majority of UK agriculture’s emissions are not carbon dioxide but methane from ruminant animals (50% of emissions) and nitrous oxide from the application of fertilisers and management of wastes and manures (40%).
• Intensive agriculture has caused arable soils to lose 40-60% of their organic carbon, while soil degradation in the UK has been calculated to cost £1.2bn every year, with four million hectares of soil at risk of compaction (in England and Wales), affecting soil fertility and water resources, and increasing the risk of flooding; while a further two million hectares of soil are at risk of erosion in England and Wales.
• In the last 50 years, almost 60% of UK species including starlings, hedgehogs and pine martens, have declined. This is significantly higher than the global average. A quarter of native UK mammals are now at threat of extinction, much of which is driven by the destruction of their habitat. Agriculture, covering 70% of UK land, is the primary factor, highlighting the need to produce our food with less land and avoid highly inefficient practices like growing crops for animal feed.