We talk a lot about C02 but there are other greenhouse gases that are responsible for GW.
METHANE
CARBON DIOXIDE | METHANE | NITROUS OXIDE
Methane is 21 times more powerful a greenhouse gas than CO2 and is responsible for nearly as much global warming as all other non-CO2 greenhouse gases put together. It has many sources, and lots of potential to cause major damage.
Methane is a clear, odourless gas produced when organic matter decays. It's also produced naturally by farm animals. Humans produce methane in our agricultural and industrial processes. It even comes out of our food waste. Methane has staying power. Each molecule of methane gas hangs in the atmosphere for about twelve years before eventually breaking up.
ANIMAL AGRICULTURE
Animal agriculture produces more than 100 million tons of methane a year.1 Methane production is on the rise, as meat consumption has risen. About 85% of methane from animal agriculture is produced in the digestive processes of livestock.2 Another 15% of animal agricultural methane emissions are released from the large stores of untreated farm animal waste.3
FARMING
Rice paddies are the number-one source of human-produced methane, producing up to 25% of global methane emissions. The warm, waterlogged soil of rice paddies encourages methanogenesis—which happens when a single-celled organism produces both methane and carbon dioxide.4 It's slightly problematic that rice is one of the world's key food staples.
BIOGENIC METHANE
Biogenic methane comes from organic materials as they decompose in oxygen-free environments.5 For example, when you tied up that plastic bag of dog poop. The largest sources are wetlands, livestock, and landfills. Formation of methane in this manner usually takes place close to the surface of the earth, and the methane produced is usually lost into the atmosphere.
FOSSIL FUEL PRODUCTION
When organic material decomposes below the earth's surface, methane often becomes trapped underground in small gaps in the rocks. Mining in these areas allows the methane to escape, and if it's not collected it seeps into the atmosphere. Underground coal seams inevitably contain significant amounts of methane. In some cases it is possible to collect this from the mine and burn it as a fuel; however, in other mines the ventilation system expels it to the atmosphere.
1 Source: www.earthsave.org/globalwarming
2 Source: Ibid.
3 Source: Ibid.
4 Source:
http://toxics.usgs.gov/definitions/methanogenesis.html
5 Source:
http://www.guardian.co/uk/climatechange/storu0,12374,1684378,00.html
NITROUS OXIDE
NITROUS OXIDE
CARBON DIOXIDE | METHANE | NITROUS OXIDE
Here's a real bad guy: Nitrous oxide. Although it comes from both natural and manmade processes, it's a potent greenhouse gas that is 170 to 290 times stronger a greenhouse gas than carbon dioxide.
NO2 has an atmospheric lifetime of over 121 years and is responsible for 6% of human-caused global warming. The main sources of nitrous oxide are fossil fuel combustion (like from power stations), fertilizers, burning rainforests and animal waste.
TRANSPORTATION
Nitrous oxide spews out of cars. Current estimates of the amount of transport-related NO2 range from 110 to 240 thousand tonnes per year. As car culture spreads around the globe and more and more people begin to drive, nitrous oxide emissions will continue to rise. And it's not just cars. Nitrous oxide emissions come from other forms of fossil-fuel-powered transport, including planes, boats and trucks.
AGRICULTURE
Agricultural soil is the second largest—and growing—global source of nitrous oxide. Global emissions range from 2 to 4 million tonnes annually. Mostly it comes from fertilizer application, and a small amount is released from burning crop residues. Burning biomass produces about half a million tonnes of nitrous oxide each year.
FERTILIZER
In our modern world, always growing, nitrogenous fertilizers are relied on to produce higher crop yields. Because of the nitrification process, use of nitrogenous fertilizer increases nitrous oxide emissions from soil and water. Fertilizer in the form of animal waste also emits substantial emissions of nitrous oxide from agricultural soils.