The current thinking is that agriculture emits about 13 percent of GHG. The problem lies in the amount of increasing percentage the future will hold. There is a real drive for terrestrial meat to be included in diets everywhere, but, that means agriculture will have an ever increasing impact. Facing that fact means agricultural GHG have to be addressed.
And, yes, factory farms are a problem. It is really strange to think of the world moving in a different direction than the USA. Perhaps it is being out of touch, but, it seems to me more Americans are looking to vegetables and their products to satisfy a healthy diet. Yet, the world wants to eat meat. The reason so much movement exists in producing meat for a global diet is because the fisheries in many countries are failing. Another negative feed back loop of the climate crisis.
In today’s world (click here) there are a host of serious environmental problems, and factory farming is one of the top causes of pollution. Scientific
research has found that factory farming’s method of crowding and
confining animals in warehouse-like conditions before killing them and
mass-producing both “meat” from cows, pigs and chickens as well as dairy and eggs poses “an unacceptable level of risk to public health and damage to the environment…” Yet,
despite factory farming’s severe social and ecological costs, many
governments promote this unsustainable industry to supply a growing
global “meat” market that is projected to double by 2050....
...Unlike human waste, animal excrement from factory farms is not processed
as sewage—making it about 500 times more concentrated than treated
human waste while leaving pathogens (like Salmonella and E. coli) and volatile chemicals intact. Even
so, farmers typically spray some liquidized manure onto the food being
grown for animals using giant sprinkler jets, and store the rest in
open-air cesspools that can be as large as several football fields and hold millions of gallons of waste. However, neither of these dispersal techniques is environmentally safe or sustainable....
...Various gases from animal waste are all major sources of factory farm air pollution, and
particulate matter and bacterial toxins found in high concentrations at
and around industrialized animal facilities have caused serious
respiratory and cardiac disorders. The
ammonia from waste slurry lagoons also breeds bacteria, which creates
acid that evaporates and combines with nitrous oxide from fertilizers
and industrial pollution to form nitric acid rain—which leaches
nutrients from the soil, despoils forest habitats, and kills fish by
releasing toxic minerals from the earth that flow into aquatic
ecosystems. Even though agricultural fertilizer emissions are the
leading cause of nitric acid rain (after motor vehicles and coal
plants), they remain virtually unregulated in the U.S.
In addition, animal agriculture is responsible for more than half of humanity’s total greenhouse gas emissions (largely
created by using arable land to grow food for animals, animal belching
and flatulence, and chemical emanations from manure). This includes 37
percent of anthropogenic (i.e., human-made) methane, and methane gas is
23 times more potent a climate change agent than carbon dioxide. Yet,
despite factory farming’s leading role in the climate change crisis,
the EPA does not currently have the authority to regulate the U.S.
livestock industry’s greenhouse gas emission...