demographic momentum

The time-lag between any change in the rate of increase of a population and its effect on total population number. The more rapid the increase the greater the momentum. Demographic momentum in the human population is such that even strict restraint would have little effect on total population number on a time-scale of decades, suggesting that emphasis should also be given to reducing environmental impact by lowering of consumption rate.

This definition is abridged from A – Z of tree terms: A companion to British arboriculture.
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