In its first projection of the world\'s population in the next three centuries, the U.N. Population Division forecast the rise to about 9 billion from the current 6.3 billion people, providing the trend toward smaller families continues.
If fertility levels in the developing world remain at today\'s levels, the global population would reach 244 billion in 2150 and 134 trillion in 2300, according to the report, \"World Population in 2300.\"
\"It\'s like the Titanic with an iceberg ahead,\" said Joseph Chamie, director of the population division. \"You sink because the rates are so low or you simply grow too rapidly because the rates are too high. Either way you have to change course.\"
Even small changes could make a huge difference, he said. The 9 billion estimate is based on a two-child family, but one-quarter of a child more per family could boost the population in 2300 to 36.4 billion.
\"It\'s like if you are too obese you could die,\" Chamie said. \"But if you are too light and you start wasting away, you could die because you are underweight. It\'s the same with population, being too large, too small, growing too rapidly or too slowly,\" he said.
The projections for three centuries in advance are the most distant forecast ever given by the United Nations. Chamie maintained policy-makers struggling with climate change, agriculture production and immigration needed long-term projections to take corrective action.
LIVING LONGER WITH SMALLER FAMILIES
People in rich countries will live much longer by 2300. Americans, Swedes and Japanese can expect life expectancies of more than 100 years on average, with Japanese expected to live to 108. In China, people are expected to live until 85.
Worldwide, the median age will rise to nearly 59 years in 2300 from 26 years today. That means the number of people aged 60 or over would increase to 38 percent in 2300 from 10 percent of the world\'s population today.
The good news, according to Chamie, was a trend toward smaller families in a variety of nations. He noted two children were the norm in such countries as Iran, Brazil, Indonesia, Mexico and Thailand.
\"Men and women are attaining some control over the number and spacing of children,\" he said in an interview. But in Europe, Japan, Australia and Canada, families are too small. The report warns that at current levels of 1.4 children per family and no increase in immigration, there would only be 232 Europeans in 100 years for every 1,000 today.
Russia, Italy and Spain would only have about 1 percent of their current size if they did not increase the number of children by 2300. The population in all of Germany would be down to the current size of Berlin, Chamie said.
Some nations, like Italy, are taking remedial steps and offering more than $1,200 for the birth of a child.
The United States is nearly alone among industrial nations in seeing an upward trend, in part due to immigrants, who have more children in the first generation and what Chamie calls native optimism with \"people thinking the future is brighter.\"
The United States has 295 million people today and projections are for a doubling to 523 million by 2300.
In Africa, the population will double to 2.3 billion people, from 13 percent of the world\'s people today to 24 percent in 2300, assuming treatment for AIDS is widespread.
Latin America and the Caribbean will remain about the same or decline slightly. Asia is expected to decrease to 55 percent percent of the world\'s population by 2300, from 61 percent, the report said.