The document discusses global population growth and its variations among different nations. It notes that while some nations have very high growth rates above 3%, others have stable or even declining populations. The world population reached 7 billion in 2011 according to the UN and is projected to reach over 10 billion by 2050 if current growth trends continue. Rapid population growth puts pressure on natural resources and can degrade the environment if demands for food, water and energy are not met sustainably.

1. Global Population Growth :
Variations Among
Nations

2. Concept :
•This section examines the interface between the growth
in human population and the
environment.
• The population growth rates vary from nation to
nation
•Some nation show very high growth rates above 3 per
cent.
• On the other hand some nations are not growing at all
and few have declining population.

3. Global Human Population:
• The global human population at present is around 6 billion.
It will cross the 7 billion mark by 2015.
• The world population is growing by more than 90 million
per year.
• Present projections show that if our population growth is
controlled, it will still grow to 7.27 billion by 2015.
• However, if no action is taken it will become a staggering
7.92 billion
It is not the demographic figures
alone that need to be stressed, but an appreciation of the
impact of this demographic growth on natural resources.

4. • The needs of this huge number of human beings cannot be
supported by the Earth’s natural resources, without degrading
the quality of human life.
U.S estimation:
As of today's date, the world population
is estimated by the United States Census Bureau to be 7.011
billion.
• The US Census Bureau estimates the 7 billion number was
surpassed on 12 March 2012. According to a separate estimate
by the United Nations,

5. Population Growth Among Nations:
In 1800 the vast majority of human
population i.e., 86% resided in Asia and Europe with 65%
alone in Asia.
• In 2000 the world had 610 crore population which is
expected to increase up to 10 billion by the year 2050 if the
same trend continues.
• Some terms which are frequently used with population
growth are
•. Birth rate: the no of live births per 1000 population in a
given year.

6. • Earth’s population exceeded 7 billion in October 2011, a
milestone that offers unprecedented challenges and
opportunities to all of humanity, according to UNFPA, the
United Nations Population Fund.
• According to papers published by the United States Census
Bureau, the world population hit 6.5 billion (6,500,000,000)
on 24 February 2006.
• The United Nations Population Fund designated 12
October 1999 as the approximate day on which world
population reached 6 billion. This was about 12 years after
world population reached 5 billion in 1987, and 6 years after
world

9. • Growth rate: the no of persons added to a population in a
year due to natural increase.
• Doubling time: the no of years required for the population
of an are to double its present size.

12. Decrease of Death Rate:
Improved medicine, sanitation and nutrition
have produced a major decrease in death rates.
• Between 1940 and 1960, the falling death rates in Egypt
caused average life expectancy to increase by 20 yrs.
• Most western countries have low birth rates that their
populations are approaching stability.

13. • The united states population doubled from 135 million to
270 million during the past 60 yrs and is expected to increase
up to 540 million in the next 70 yrs at a current t rate of 1%/yr.
china’s population is increasing at a rate of 1.1%/yr.
• India’s current population growth rate is 1.9% / yr. together
china and India constitute more than 1/3rd of the world
population.

14. Effects on Natural Resources:
In the near future, fossil fuel from oil fields will run dry
• Existing agro systems will become too overburdened and
will not be able to meet the demands for food.
• Pastures will be overgrazed by domestic animals.
• The industrial growth required to meet the demands of the
massively rising population will reinforce pollution of soil,
water and air. Industrial gases in particular will cause greater
global warming and will eventually lead to a rise in sea levels,
flooding all low-lying areas and submerging coastal
agriculture as well as towns and cities

15. •. The seas will experience a decline in the fish population.
•Larger ozone holes will develop due to the discharge of
industrial chemicals into the atmosphere; this development in
its turn will affect human health.
•The population pressure will contribute to water the
depletion of fresh water and may lead to water ‘famines’.
•The demographic pressure will also reinforce the
degradation of ecosystems leading to extinction of thousands
of species which have a great role in the sustainability of the
planet.