Global Warming
             Global Warming
          ʕ CauseɼImpact and Mitigation ʕ
          ʕ CauseɼImpact and Mitigation ʕ
                                                                    Cause of Global Warming
                                                                    Cause of Global Warming
                        ʬPointʭ Global warming is caused by anthropogenic activities.
                            7000                                                                                                               CO2 Emission by fuel
                            6000            Gas                                                                                         Fossil fuel consumption is increasing 
                          r)                Oil                                                                                         rapidly to satisfy growing energy demand 
                          /y5000
                          tC                Coal                                                                                        after the Industrial Revolution, which 
                           (M4000                                                                                                                                                                      th
                          s                                                                                                             started at the end of the 18                                        century.
                          n
                          o
                          i
                          s
                          s
                          i 3000                                                                                                        Fossil fuel combustion ɿ
                          m
                          2 e                                                                                                                                  C         +O2 ˠ CO2
                          CO2000
                                                                                                                                                             ʢCarbon in            ʢOxide in
                            1000                                                                                                                                 Fossil fuelʣ          Atmosphereʣ
                                0                                                                                                375                                                                                  1
                                 1750            1800            1850             1900            1950            2000                         Historical CO2 record from the Siple Station ice core
                                                                          Year                                                                 Atmospheric CO2 record from Mauna Loa
                                                                                                                               ion                                                                                         e
                                                                                                                               at350           Global mean temperature relative to the mean of 1961-1990              0.5
                                                                                                                               r
                                                                                                                               t                                                                                           hang
                                  Source: Carbon Dioxide Information Analysis Center, ORNL                                     n                                                                                           c
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                                                                                                                               onc ʣ                                                                                       ur
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                                                                                                                               2                                                                                           r  ʣ
                                                                                                                                   m                                                                                       e
                                                                                                                               O 325                                                                                  0    p
                                                                                                                                C  ʢpp                                                                                     m  ʢˆ
                                                                                                                               ic                                                                                          e
                                                                                                                                                                                                                           an t
                        Atmospheric CO2 Concentration                                                                          pher                                                                                        e
                                                                                                                               s
                                                                                                                               o
                                                                                                                               m 300                                                                                  -0.5bal m
                                                                                                                               t                                                                                           o
                          and Global mean Temperature                                                                          A                                                                                           l
                                                                                                                                                                                                                           G
                            Atmospheric CO2 concentration  and 
                            global mean temperature increase with                                                                275                                                                                  -1
                                                                                                                                    1750           1800            1850           1900            1950           2000
                            the rapid increase of CO2 emission.                                                                                                            Year
                                                                                                                                                      Source: Carbon Dioxide Information Analysis Center, ORNL
                                                Carbon Cycle
                                                Carbon Cycle
                               ʬPointʭ CarbonʢCʣ circulates on the Earth.
                                                                         The carbon (C) circulates among 
                                                                         terrestrial plants, the atmosphere 
                                                                         and the ocean, undergoing various 
                                                                         reactions.
                                                                         For example,
                                                                           Solution 
                                                                                                     +     2-
                                                                                   ɿ CO + H O ⁶ 2H + CO
                                                                                        2   2             3
                                                                            Photosynthesis 
                                                                                   ɿ 6CO + 6H O ˠ 6O + C H O
                                                                                         2     2        2   6 12 6
                                                                        However, anthropogenic activities 
                                                                        like fossil fuel burning and 
                                                                        deforestation have released carbon 
                                                                        (C) to the atmosphere and have 
                                                                        increased the carbon in the 
                                                                        atmosphere.
                                                                           Burning ɿ C + O2 ˠ CO2
                                                                        This carbon increase in the atmosphere  
                                                                        leads to the global warming.
                  Greenhouse Effect
                  Greenhouse Effect
        ʬPointʭ CO2ʢcarbon dioxideʣ plays an important role 
                  to keep the earth warm.
                                  Greenhouse gases, e.g., CO2,
                                  absorb infrared radiation, 
                                  while solar radiation passes 
                                  through gas layer.
                                 Certain amounts of greenhouse 
                                 gases (CO2 etc) are necessary to 
                                 keep the earth warm.