Population growth driving climate change, poverty - experts

Unchecked population growth is speeding climate change, damaging life-nurturing ecosystems and dooming many countries to poverty, experts concluded in a conference report.

Unless birth rates are lowered sharply through voluntary family-planning programmes and easy access to contraceptives, the tally of humans on earth could swell to an unsustainable 11 billion by 2050, they warned.

The UN currently projects that global population will rise from 6.8 billion today to between eight and 10.5 billion by mid-century.

The researchers said that with one and a half million more humans climbing aboard the planet every week, a recipe is looming for ecological overload, famine and broken states.

"Continued rapid population growth in many of the least developed countries could lead to hunger, a failure of education and conflict," said Malcolm Potts at the University of California in Berkeley, which hosted the conference in February.

The papers are authored by 42 specialists in environmental science, economics and demography.

"There is no doubt that the current rate of human population growth is unsustainable," summarised Roger Short, a professor at the University of Melbourne in Australia.

"The inexorable increase in human numbers is exhausting conventional energy supplies, accelerating environmental pollution and global warming and providing an increasing number of failed states where civil unrest prevails."

Ninety-eight per cent of the expected population growth will occur in developing countries, especially in Africa, where numbers are set to double to almost two billion by 2050.

"How Niger is going to feed a population growing from 11 million today to 50 million in 2050 in a semi-arid country that may be facing adverse climate (change) is unclear," said Adair Turner, a member of Britain's House of Lords. The population of Uganda was five million in 1950, is 25 million today and could reach 127 million by 2050, Mr Turner said.

Concern about population growth is not new.

It was most famously articulated by a British mathematician, Thomas Malthus, who in 1798 - when earth was home to about one billion - calculated that exponential growth would inevitably lead to famine.