UN: World population 11 bil. by 2100 as fertility soars in Africa

Posted Jun 14, 2013 by JohnThomas Didymus
According to a new UN report issued on 13 June, the current world population of about 7.2 billion could reach 11 billion by the end of the century, about 800 million or 8 percent in excess of the previous projection of 10.1 billion people.
A market in Lagos  south west Nigeria.
A market in Lagos, south west Nigeria.
Zouzou Wizman
The rise in world population in excess of previous projections is due mostly to soaring fertility rates in Africa that UN demographers had underestimated. According to the Director of the Population Division in the UN Department of Economic and Social Affairs, John Wilmoth, "In some cases, the actual level of fertility appears to have risen in recent years; in other cases, the previous estimate was too low."
Wilmoth said: "While there has been a rapid fall in the average number of children per woman in large developing countries such as China, India, Indonesia, Iran, Brazil and South Africa... rapid growth is expected to continue over the next few decades in countries with high levels of fertility such as Nigeria, Niger, the Democratic Republic of the Congo, Ethiopia and Uganda and also Afghanistan and Timor-Leste, where there are more than five children per woman."
The expected population changes from 2013 to 2100 are shown in the graphic below. Eight of the top 10 countries expected to contribute most to the global population increase are in Africa.
The largest increase is expected in Nigeria, with India second on the list. The report notes that India is expected to become the world’s largest country, surpassing China's population sometime around 2028 at 1.45 billion. India's population is expected to continue growing after it has surpassed China' s, while China is expected to experience a decline of about 300 million (the largest decline projected for any country) from 1.4 billion to 1.1 billion in 2100.
Nigeria's population is estimated now at 184 million. It is expected to balloon to 914 million in 2100, a more than fourfold increase. The country's population is expected to surpass that of the US before 2050.
The United States is the eighth on the list of countries with projected highest population increase. The US is expected to post a growth of 146 million or 46 percent, from 316 to 462 million in 2100.
Africa's population of 1.1 billion is expected to quadruple by 2100 and reach 4.2 billion.
The latest UN estimates are based on statistical analytically methods developed by Adrian Raftery, a professor of statistics and sociology, and his colleagues at the University of Washington's Center for Statistics and Social Sciences. The new statistical method was used to estimate the growth in Africa's population following a previous estimate conducted two years age believed to have underestimated fertility rates in Africa.
Expected population changes from 2013 to 2100
Expected population changes from 2013 to 2100
University of Washington Center for Statistics and Social Science
According to Raftery: "The fertility decline in Africa has slowed down or stalled to a larger extent than we previously predicted, and as a result the African population will go up."
Other areas of the world outside Africa are expected to post only minor population changes. The researchers project a population decline in Europe due to below replacement fertility levels. Experts have warned of the dire consequence of rapidly aging population for Europe, which is the problem of providing care for a growing non-productive section of the population.
According to the UN Under-Secretary-General for Economic and Social Affairs, Wu Hongbo: "Although population growth has slowed for the world as a whole, this report reminds us that some developing countries, especially in Africa, are still growing rapidly."
The report notes that the population of more developed regions of the world will remain largely unchanged at around 1.3 billion from 2013 until 2050. However, the combined population of the 49 least developed countries will double in size from 900 million in 2013 to 1.8 billion in 2050.
Raftery noted that in spite of the projected large increases in population, the international community has shifted attention to other global issues such as climate and poverty which he notes are related to the problem of population increase.
One of the major points of difference between Raftery's and previous methods are the alternate projections based on different birth rate scenarios reflecting high and low ranges of estimates. These introduce significant uncertainty, yielding widely variable projections of 7 and 17 billion for world population by 2100.
However, the UW research group estimates are based on probabilities of future levels in conjunction with best forecasts. Raftery said: "Our probability intervals are much tighter, ranging from 9 billion to 13 billion in 2100."
Experts have long recommended that the most efficient means for slowing population growth are equal rights, education for women, family planning and access to contraception.
According to Suzanne Ehler, president of Population Action International: "Right now, 222 million women in the developing world lack access to modern contraception. This has far-reaching consequences for their health, and their opportunities to get an education, earn an income, take care of their families, and determine their own futures. The fact that any woman does not have the tools to decide the size of her family is absurd. That 222 million women do not is a tragedy, and a huge opportunity for all of us to do more."
According to the UN, global population reached 7 billion in 2011. It passed 6 billion in 1999.