Green House Effect and Gases

  Carbon Cycle

The discussion of Global Warming should and always starts with the carbon cycle as the changes in this cycle is the main cause of global warming.

Carbon Cycle - Components

Atmosphere carbon dioxide and methane, carbon dioxide reacts with water molecules and forms carbonic acid, human activities, released by plant respiration

Terrestrial biosphere - carbon stored in soils, in plants and other living organisms, released by combustion and respiration

The Oceans - including dissolved inorganic carbon and living and non-living marine biota. The sediments calcium carbonate, including fossil fuels

Oceans important role in CARBON SEQUESTRATION (a natural or artificial process by which carbon dioxide is removed from the atmosphere and held in solid or liquid form)

Nature has appropriate balance for everything, but changes occur when anthropogenic changes exceed the carring capacity the buffring capacity of Earth. The main cause for Global Warming is Green House Effect.




  Green House Gases (GHGs)

Major Green House Gases (listed in Kyoto Protocol internationally accepted)

  1. Carbon dioxide (CO2)
  2. Methane (CH4)
  3. Nitrous oxide (N2O)
  4. Hydrofluorocarbons (HFCs)
  5. Perfluorocarbons (PFCs)
  6. Sulphur hexafluoride (SF6)


Water vapourr are also a major green house gas but as its life is very short thus not considered in this list.

  Sources of GHGs

Carbon dioxide (CO2) - Fossil fuel use is the primary source of CO2. The way in which people use land is also an important source of CO2, especially when it involves deforestation. Land can also remove CO2 from the atmosphere through reforestation, improvement of soils, and other activities. We are releasing more and mor CO2 by fossil fuels and reucing the sequestration process by cutting forests.

Methane (CH4) - Agricultural activities, waste management i.e mainly landfill gas, livestock and energy use all contribute to CH4 emissions

Nitrous oxide (N2O) - Agricultural activities, such as fertilizer use, are the primary source of N2O emissions

Fluorinated gases (F-gases) - Industrial processes, refrigeration, and the use of a variety of consumer products contribute to emissions of F-gases, which include Hydrofluorocarbons (HFCs), Perfluorocarbons (PFCs), and Sulfur hexafluoride (SF6)

Black carbon (BC)/ Soot is a solid particle or aerosol, not a gas, but it also contributes to warming of the atmosphere. However, it traps the short wave solar radiation rathe than long wave trapped by GHGs. Either ways the temperature of Earth increases.

Global GHG Emissions : As per IPCC 2014; based on global emissions from 2010. (IPCC stands for Intergovernmental Panel on Climate Change)




CO2 from fossil fues burning is still the major cause of GH Effect and Global Warming followed by methane which is increasing tremendously.


  Global GHG emissions by Economic Sectors

 As per IPCC 2014

Energy Sectors always ranks first in GHG emission but now is very close to Agriculture, Forestry and LULUCF  followed by industries and transport sector.


  Emission by Countries

As per 2011 global emission data; the emission mainly considered usage of fossil fuels combustion and some industrial processes

China is ranks first followed by US and EU. India though have very less emission but is increasing due to developmental activities.