Agriculture and Global Warming
The resources ploughed into agriculture in developed countries are enormous. The total transfers to agriculture in countries in the Organisation for Economic Cooperation and Development for 2003 amounted to $350bn (£194bn, €288bn), half of which comes from taxpayers and half from consumers. Eliminating all agricultural policy distortions could produce global annual welfare gains up to $165bn according to the Food and Agriculture Organization because production would move to countries with comparative advantages. The global cost of not eradicating hunger—in terms of conflicts, recurrent emergencies, international crime, the drug trade, terrorism, clandestine migration, and the premature death of those who are hungry—is enormous. To this should be added the cost of environmental damage from agriculture, which might be even higher.
Current dietary energy supply is more than sufficient to alleviate starvation worldwide and is forecasted to grow for another 25 years
Agriculture subsidies coupled to production distort the balance between supply and demand, leading to overconsumption and obesity
Overproduction of food in rich countries using trade distorting measures undermines the agricultural sectors in developing countries, hindering the eradication of hunger and poverty
Phasing out of agricultural producer support in developed countries is the first step in the fight against both obesity and hunger
Climate change and agriculture are interrelated processes, both of which take place on a global scale. Global warming affects agriculture in a number of ways, including through changes in average temperatures, rainfall, and climate extremes (e.g., heat waves); changes in pests and diseases; changes in atmospheric carbon dioxide and ground-level ozone concentrations; changes in the nutritional quality of some foods; and changes in sea level.
Climate change is already affecting agriculture, with effects unevenly distributed across the world. Future climate change will likely negatively affect crop production in low latitude countries, while effects in northern latitudes may be positive or negative. Animal agriculture is also responsible for CO2 greenhouse gas production and a percentage of the world's methane, and future land infertility, and the displacement of local species.
Agriculture contributes to climate change both by human-caused greenhouse gases and by the conversion of non-agricultural land such as forests into agricultural land. Agriculture, forestry and land-use change contributed around 20 to 25% of global annual emissions in 2010.
In the report published in 2014 the Intergovernmental Panel on Climate Change says that the world may reach "a threshold of global warming beyond which current agricultural practices can no longer support large human civilizations." by the middle of the 21st century. In 2019 it published reports in which it says that millions already suffer from food insecurity due to climate change and predicted decline in global crop production of 2% - 6% by decade
How does animal agriculture cause global warming?
One of the main ways in which the livestock sector contributes to global warming is through deforestation caused by expansion of pasture land and arable land used to grow feed crops. Overall, animal agriculture is responsible for about 9% of human-caused carbon dioxide emissions globally (UN FAO).
Animal agriculture is also a significant source of other greenhouse gases. For example, ruminant animals like cattle produce methane, which is a greenhouse gas about 20 times more potent than carbon dioxide. The livestock sector is responsible for about 37% of human-caused methane emissions, and about 65% of human nitrous oxide emissions (mainly from manure), globally (UN FAO).
Beef is a bigger problem than other sources of meat
Producing beef requires significantly more resources (e.g. land, fertilizer, and water) than other sources of meat. As ruminant animals, cattle also produce methane that other sources (e.g. pigs and chickens) don't.
US academics estimated that producing beef requires 28 times more land, 6 times more fertilizer and 11 times more water than producing pork or chicken.