human activites like Fossil fuel burning Green house gasses Deforestiration Industrialization Agriculture these al are the major factor of climate change in 21th century

1. Contribution of human in
climate changes

2. Climate:

10.  Carbon dioxide (CO2) is the primary greenhouse gas emitted
through human activities.
 In 2011, CO2 accounted for about 84% of all U.S. greenhouse
gas emissions from human activities
 Carbon dioxide is naturally present in the atmosphere as
part of the Earth's carbon cycle
Carbon cycle:
 the natural circulation of carbon among the atmosphere,
oceans, soil, plants, and animals

11. Carbon cycle

12. Co2 level increased

15. Methane level

22. increase in level of nitrous oxide as a
green house gas up to 1975

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