POPULATION THEORY-Maximum Limit:Earth can hold 60m billion
Kate RaviliousLondon

IF YOU thought the planet was already struggling under the weight of billions of humans, think again. Researchers have worked out the population's ultimate limit, and claim the Earth could withstand up to 200,000 times as many of us.

The world's population is expected to rise from 6.5 billion today to around 9 billion in 2050, but according to Viorel Badescu at the Polytechnic University of Bucharest in Romania that is nowhere near the limit of the planet's capacity.

Dr Badescu's calculations, which appear in the International Journal of Global Energy Issues next month, are based on earlier work by the British physicist John Fremlin. In 1964 Fremlin suggested that the Earth would be habitable as long as the amount of heat it received, from activity on the surface and incoming sunlight, equalled the heat it gave out. Too many people and, just like an overcrowded party, the planet would get too hot to handle. On that basis, Fremlin concluded that the largest population the Earth could comfortably sustain was 60 million billion.

Badescu and Richard Cathcart, a geographical consultant in Burbank, California, repeated Fremlin's calculations, using more up to date thermodynamic models. Assuming that every person emits 120 watts of heat and that it would be uncomfortable if the average temperature at the Earth's surface rose too much, the researchers declared the Earth could sustain 1.3 million billion people without overheating.

Writing in the journal, the researchers acknowledge the Earth's resources could be put under severe strain long before the theoretical population peak is reached. "Constraints like food availability or physiological necessities may become critical in the relatively near future. But they are subjected to a continuous change as a result of the development of human civilisation and technology," Dr Badescu said.

If those hurdles can be overcome, and it is a big if, the scientists believe their calculation gives the ultimate upper limit on the world's future population.

Describing the Earth should such a limit ever be reached, Cathcart paints a picture where we see little, other than our neighbour's armpit, or our neighbour's neighbour's armpit.

Daylight would be a rare luxury, with most people living in skyscrapers 2,000 storeys high.

"It's a hideous prospect. Earth would look like Death Star from the Star Wars," Cathcart said.

*Source:www.hindustantimes.com,Mumbai Edition(Life,The Universe),dated-December 28,2005.*