Environmentally Speaking....

                                                                     

           THE ENHANCED GREENHOUSE EFFECT

 

                TAMPERING WITH THE EARTH’S THERMOSTAT

The 21^st century will undoubtedly bring many changes and challenges, some of which may surprise us. But, one change is evident already - CLIMATE CHANGE - and responding to it will certainly be challenging for all of society.  Our climate has been relatively stable for millennia, providing the opportunity for our species to prosper and flourish.  Now we are confronting the reality that human activities have been changing our atmosphere and have altered the balance of Earth’s natural climate system.

 

 

                          UPSETTING A DELICATE BALANCE

                                     

                                       What are the Greenhouse Gases?

 

  Greenhouse Gas                        Description                                                                                          Atmospheric Lifetime (yrs)

 

Water Vapour (H2O)        - Most common greenhouse gas                                                0
                                        - Responsible for about 2/3 of the natural
                                          greenhouse effect.

                                        

                                       Note: Human Activity is not a direct influence to any

                                                  significant degree.

 

 

Carbon Dioxide (CO2)      - Naturally occurring gas produced by living                            Variable
                                          organism and fermentation (decay).
                                        - Burning (combustion) of hydrocarbon based fuels                        
                                        - Deforestation
                                        - Biomass burning (agriculture, wood materials,
                                           municipal waste etc…)  
                                        - Industrial processes (aluminum smelting,
                                           lime production)      

 

 

Methane (CH4)                - Naturally occurring flammable gas, emitted by                    12 estimated     
                                          geological coal formations + decomposition of  
                                          of organic matter.  CH4 emissions include:
                                        - Manure management
                                        - Biomass burning
                                        - Natural gas delivery systems
                                        - Landfills
                                        - Coal mining
                                        - Enteric fermentation2

Nitrous Oxide (N2O)         - Naturally occurring from microbial                                            120
                                          action in soil
                                        - Application of nitrogen fertilizers
                                        - Soil Cultivation
                                        - Production of nitric acid and adipic acid and
                                          the combustion of fossil fuels and wood  

 

 

Sulphur  Hexafluoride (SF6)   - Used for the production of magnesium                                   3200
                                           - It can also be used as insulating material
                                             for high-voltage transformers and circuit breakers

 

 

Perfluorocarbons (PFCs)        - PFCs are principally emitted as by-products during            2600 to 50 000
                                             aluminium smelting.
                                                         
                                    Note:  There are 7 different types of PFCs

 

Hydrofluorocarbons (HFCs)     - Used in refrigerators and air condition systems,                   1.5 to 264
                                              firefighting agents, aerosols, foam-blowing agents.
 
                                    Note:  There are 13 different types of HFCs

 

Ozone (O3)                          - Small traces of ozone occur naturally in the lower                       N/A
                                             atmosphere, however, most of the ozone now found
                                             at group level is the result of chemical reactions involving
                                             pollutants produced by human activities. Ozone exists naturally
                                             in the upper atmosphere where it plays an important
                                             role in shielding the Earth from the sun’s harmful
                                             ultraviolet rays. 
 
                                    Note:  There are also many natural things that put CO2 into
                                               the atmosphere:  forest fires, volcanoes, decomposing
                                               trees, plants and, gas bubbles from ocean surfaces.