Background Material

Population
"If we continue to have children at our current rate, according to UN projections, by the end of this century there will be 28 billion of us.
(This refers to the Constant Fertility Variant Projection from the 2012 Revision of the UN World Population Prospects)"
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Climate
...obviously 'climate' is not the same as weather. But climate is one of Earth's fundamental life support systems, one that determines whether or not we are able to live on this planet.

It is generated by four components. The atmosphere, the air that we breathe. The hydrosphere, the planet's water. The cryosphere, the ice sheets and glaciers, and the biosphere, the planet's plants and animals.
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