The composition of the atmosphere will be maintained. Whatever is added will be exactly removed.
War will be a thing of the distant past.
Everything will be in equilibrium.
How long will it take to get there? On the metric of everyone being at least middle class, let us do some simple math. Say 5 billion need to be raised out of poverty, averaged over the time required. If this needs a 100,000 $ investment in their education and employment creation, it will take 500 trillion USD. If the World Gross Product is 80 trillion USD and 10% of this is available for poverty alleviation (with the rest being for maintaining the 7 billion existing population) then it will take 500 / 8 = 62.5 years.
So in about 3 quarters of a century more we could achieve equilibrium on Earth?
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