World population to peak at 9.2 billion in 2050
March 13, 2007
The report also said that global population will age faster than ever before, with half the expected increase in world population between 2005 and 2050 to be accounted for by a rise in the population aged 60 years or over. The number of children under the age of 9 will decrease slightly over the same period.
Global life expectancy will increase from 66.0 years today to 75.4 in 2045-2050, according to the report. Japan is expected to have the highest life expectancy (87.1 years versus 81.9 years today), followed by Hong Kong, Switzerland, Iceland, and Australia. The United States is expected to see life expectancy increase by six years, from 78.5 years today to 84.5 years in 2050.
The U.N. notes that fertility in less developed countries is expected to fall from 2.75 children per woman in 2005-2010 to 2.05 in 2045-2050, a figure that puts births below replacement levels of 2.1 children per woman. Least developed countries will likely see their fertility rate decline from 4.63 children per woman to 2.50 children per woman.
The new population figures are about 100 million than those released last year due to success in treating the HIV/AIDS epidemic. The U.N. expects most countries to have antiretroviral treatment programs by 2015. Antiretroviral extend life by an extra seven-and-a-half years on average for those infected with HIV/AIDS. Overall, the U.N. forecasts 32 million fewer deaths between 2005-2050 in the 62 most affected countries than it did in its prior population revision.
While it appears likely that human population will level off mid-century, the human footprint on the planet is expected to grow as larger numbers of people achieve higher levels of affluence, especially in China and India. In general as quality of life improves, a population uses more resources. For example the United States appropriates more than 20 percent of the world's resources despite having less than 5 percent of global population.
This article uses quotes from an Iowa State news release.