The cover story inThe Economist this week predicts that population will peak this century:
Last year the United Nations said it thought the world’s average fertility would fall below replacement by 2025. Demographers expect the global population to peak at around 10 billion (it is now 6.5 billion) by mid-century.
This peak is only temporary. Fertility plotted vs. money income is U-shaped. Poor can’t afford family planning, but the rich want to have kids.
They further opine:
States should not be in the business of pushing people to have babies.
Yes they should. A baby will become a taxpayer and a useful citizen. Zero population growth did far more to hold back development of China and India than Reagan’s (anti-) family planning policies.
We can grow food indoors, reuse our water and get the energy to do it from carbon free sources. The carrying capacity of the Earth is easily one trillion people. At the current rate of waste heat per person, we would be generating only 2% of what we get from the Sun. We could site 72 billion at the density of the Netherlands, 3.8 trillion at the density of Manhattan with the current land area.