Population bomb 'ticks louder than climate'

Global population growth is looming as a bigger threat to the world's food production and water supplies than climate change, a leading scientist says.

Speaking at a CSIRO public lecture in Canberra yesterday, UNESCO's chief of sustainable water resources development, Professor Shahbaz Khan, said overpopulation's impacts were potentially more economically, socially and environmentally destructive than those of climate change.

''Climate change is one of a number of stresses we're facing, but it's overshadowed by global population growth and the amount of water, land and energy needed to grow food to meet the projected increase in population. We are facing a world population crisis.''