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Demography
Introduction
In 1999, there were 6 billion people living on Earth, and by 2011 or 2012, the population will reach 7 billion.
Why is the world population increasing so fast ?
And what will happen in the future
Population growth today
Every second, on average, four babies are born.
Every second, on average, two people die.
Every second, on average, the population increased by two people.
Two more people per second means 200 000 more people per day, and 75 million more people per year. In other words, the world population – 6,5 billion in 2005 – is growing by 1,2 percent each year.
At this 1,2 % annual growth rate, the population doubles evrey 60 years. If the number of people on Earth carried on increasing at this speed, the 6,5 billion in 2005 would become 13 billion in 2065, 26 billion in 2125 ans so on. But the population does not grow at the same speed indefinitely. On the contrary, the United Nations predict that the world population will level off at around 9 billion people before the end of the century.
Why is that ?
World population history
Throughout most of human history, the number of people on Earth could be counted in just hundreds of thousands or in millions, and the population increased very slowly. Two thousand yeras ago, there were around 250 million people in the world, and by the end of the 18th century the total had reached one billion.
At around that time, the population started growing much faster. From one billion in 1800, it rose to two billion in 1927, 3 billion in 1960, 4 billion in 1974, 5 billion in 1987 and 6 billion in 1999.
Whe should reach 7 billion by around 2011 or 2012, and growth will not stop there. So what will happen next ?
The United Nations are forecasting that the world population will level off at a mere » 9 billion by around 2050.
How did they reach this figure ?
And looking back in history, why did the population grow so slowly up
The demographic transition