Animal Agriculture and the Environment

Deforestation

Approximately 80% of global deforestation is caused by extensive cattle ranching, which is responsible for 340 million tonnes of carbon to the atmosphere every year. Livestock farming currently occupies 45% of global surface area, as well as an additional 10% for feed crops. Land is cut or burned to make room for cattle grazing and feed crop production, which threatens biodiversity, decreases carbon absorption, increases the risk of natural disasters and disrupts water cycles. Already more than 15% of the Amazon has been destroyed which doesn't even include the land loss from fires which were mainly started illegally by cattle
ranchers.

Raising animals for food always requires more calories than the calories their meat provides humans which means that therefore, animal agriculture is more destructive than agriculture for plant-based food. For every 100 calories of crops fed to animals, we get 40 calories in the form of milk, 12 calories of chicken, and just 3 calories of beef. More than half the world's grain is fed to animals that will be raised for food. We manage to feed 60 billion farm animals whilst 14% of our 7.8 billion population remains unnourished. A plant-based diet could feed vastly more people.

Water

By 2030, the world will only have 60% of the water it needs without significant global change. The situation is expected the worsen as more people switch to Western meat-eating habits and the population expands. It takes at least three times the amount of water to feed a meat eater than a vegan as consuming animal products is incredibly resource-intensive. Farming uses about 70% of the planet's accessible water. Most of the crops fed to European farm animals comes from developing countries where drinking water is most scarce.

On top of this, animal agriculture is the number one cause of water pollution. Manure contains high levels of nitrogen and phosphor which can leach into groundwater and can pollute lakes, and rivers. This kills the fish which has a knock on effect on the health of other animals. Also, ammonia from farming can cause acid rain.

Greenhouse Gases and Climate Change

Greenhouses gases emit radiation into the atmosphere which contributes to global warming and climate change. The high levels of carbon dioxide, methane, and other greenhouses gases generate over 14% of all emissions, greater than all the transport sectors combined. Studies show that a vegan diet can cut agricultural emissions in half. If everyone went vegan, global warming could be cut by 70% which would be enough to stop and reverse the harmful effects of climate change (rising sea levels, floods, melting ice caps, droughts etc.)

The Ocean

Overfishing has led to drastic imbalances for the ocean's biodiversity and has managed to cut the total fish population in half compared to fifty years ago. The demand for tuna and mackerel in particular has become extremely unsustainable, with the two species currently at the brink of extinction. Overfishing is closely tied to bycatch which is the capture of unwanted sea life while fishing for something else. This is a serious threat to marine life, causing the loss of billions of fish, along with hundred of thousands of sea turtles and cetaceans. According to WWF, if we continue to consume fish at the rate we do, stocks of all species currently fished for food could be exhausted by 2048.

About half of the fish we consume comes from fish farms. These are often poorly managed which leads to chemicals and antibiotics seeping into waterways, fish waste affecting the nutrient level of water, and, due to cramped conditions, disease spreading through the farmed fish which could be passed on to  wild species.