The earth has a very thin atmosphere, a thin film of gas that allows life to exist on this planet. It's well accepted by this time that our actions on the surface affect the composition of the atmosphere and that the atmosphere's composition affects the temperature of the planet.
By far, the most powerful contribution to "the greenhouse effect" comes from the element methane. Methane has 23 times the warming power of carbon-dioxide (CO2). The good news is Methane dissipates 10 times faster than CO2 and it comes mostly from animal agriculture—which we can entirely abandon, unlike transportation.
There are two main sources of Methane, which are released into the atmosphere as a result of animal "husbandry". The first source of methane, mainly from cows, is from ruminant burps. Yes, a considerable, and significant part of our planet's global warming... can be traced to cows burping. It sounds funny, but don't take it lightly. As you probably already know, the temperature is due to rise 2º Celcius, even if we stop emitting greenhouse gases today.
The other major source of methane which can be attributed to the animal industry is untreated waste. As a species of engineers, humans are really good at removing and treating their own waste from their personal habitat. In the USA, animals produce 35 times more waste than humans. Uncharacteristically, none of this waste is treated at all. It shouldn't surprise us then, that these gigantic ponds of filthy shit, piss, and bacteria release copious amounts of noxious, pollutant, disgusting gases into the atmosphere (not to mention onto our fellow humans, who happen to live in the neighborhood.)
The impact that untreated waste has on the environment doesn't end with atmospheric pollution. Perhaps, the effect of methane on the atmosphere will not be fully realized in our lifetimes, but the untreated waste turning our oceans into lifeless wastelands is visible right now. There are no regulations on the treatment of livestock waste.
The reason there are stringent regulations on effluent, or the waste water that is shot back into the environment, is not just because it makes the water taste bad. The health effects on people who drink tainted water are just the beginning. The dissolved oxygen in any water body will plummet when organic matter is added to it. When the oxygen is gone nothing can live in the water.
DISSOLVED OXYGEN IS REQUIRED FOR ALL AQUATIC LIFE
ADDING ORGANIC MATTER (RAW SEWAGE) SPIKES BACTERIA GROWTH
BACTERIA BLOOMS CONSUME ALL THE AVAILABLE OXYGEN IN A WATER BODY
WHEN THE OXYGEN IS GONE THE ECOSYSTEM COLLAPSES
UNTREATED COW, PIG, AND CHICKEN WASTE IS TOTALLY LEGAL TO RELEASE INTO THE WATER CYCLE
THERE IS 37 TIMES AS MUCH ANIMAL WASTE AS HUMAN WASTE PRODUCED IN THE USA EVERY YEAR
ANIMAL WASTE IS LEFT COMPLETELY UNTREATED
Dissolved oxygen is the life of an aquatic ecosystem—animal waste causes dissolved oxygen to plummet—ecosystems lacking dissolved oxygen self-destruct.
Dead zones can be seen from space. The bacteria blooms are the only life that can survive near these points of animal waste outlet.
The planet's largest ecosystem is threatened more than anything by our terrestrial activities. The result of letting their waste run off into the water cycle is massive bacteria growth, which robs all the oxygen from the water. Once the oxygen is gone, it could be decades before life returns to those water.