Environmental stress, biodiversity loss, climate change and pressure on natural
resources signal strongly that the world is already overpopulated. But human
numbers are still exploding. Our numbers reached 6.8 billion in 2009, and are
expected to climb to 9.2 billion in 2050 – by more than a third in barely 40
years. According to United Nations projections published in 2009 – World
Population Prospects: the 2008 Revision - most of this growth will take place in
the developing world. OPT has urged leaders worldwide to be "brave" on
population growth. Urgent measures are needed to reverse population growth
to levels which can be sustained in the long term.
The Population Reference Bureau (PRB) estimated the world's annual growth at
83 million in 2009, this natural increase resulting from 139 million births minus
56 million deaths. Every week some 1.6 million extra people are being added to
the planet - a sizeable city - with nearly 10,000 arriving each hour. Already the
human species is causing serious environmental damage to its only habitat -
Earth. The long-denied consequences of exploding population on ecosystems,
food supplies and energy resources are clear to all, but peaceful population
policies continue to be low on the list of solutions. The alternatives - Nature's
methods of population control - are famine, disease and war. Without urgent
efforts to stabilise and reduce world population, can efforts to save our
environment succeed? With smaller populations, living in greater harmony with
nature, our horizons may stretch far into the future. If the world's parents had
smaller families, would their children not have a better future?
The numbers are vast. On a planet inhabited by 2.5 billion people in 1950 -
within the lifetimes of many alive today - there are now more than double this
number. Population was still growing by 1.2 per cent a year in 2009, with
fertility at an average 2.6 children per women, well above the 2.1 replacement
level, according to the PRB’s World Population Datasheet 2009.
Birth rates are falling but the number of men and women likely to have
children keeps on growing. The United Nations Population Division (UNPD) 2008
Revision medium projection of 9.15 billion population in 2050 was 100 million
lower than in its 2006 Revision, but 200 million higher than the 2002 Revision.
One reason is population momentum - the effects of high birth rates decades
ago mean that there are now twice as many fertile women worldwide today
than there were in 1970. A halving of birth rates can be cancelled out by an
increase in the number of potential mothers.