What are Greenhouse Gases?

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When energy from the sun reaches the ground, some of it is reflected and sent back into space, but some gases called greenhouse gases (GHG) keep the energy inside the atmosphere. Consequently, it warms up the earth's surface and oceans.


 There are a few main GHG:

1. Carbone dioxide or CO2: is the main GHG.Although it is scarce and doesn't trap much heat, it stays for almost a century in the atmosphere! CO2 is the cause of 80 percent go global warming. It is created by the burning of fossil fuels that we each use for heat, transport and other energy requirements. 
2. Methane: traps much more heat, but it luckily has a shorter lifespan in the atmosphere. Natural sources of methane come from it escaping from wetlands and oceans. Man-made sources include: the making of oil and natural gas, raising livestock, rice farms, landfills, and waste water treatments
3. Nitrous Oxide: is a much more efficient GHG and it lasts about 150 years in the atmosphere, but it is very scarce. There are natural sources, but most of it comes from human emissions. For example: burning fossil fuels and biomass, and the use of fertilisers that contain nitrogen.