Title: Population
1Population
2If we shrank the Earth's population to a village
of 100 people, with all of the existing human
ratios remaining the same, there would be
57 Asians
52 females 21 Europeans
48 males 8 Africans 14
people from the Western Hemisphere
(north and south) 30
Christians
6 U.S. citizens holding 70 Non-Christians
60 of the worlds wealth 70 unable to
read 1 with a
college education 80 living in substandard
housing 1 with their own computer 50
suffering from malnutrition 1 near
death
1 near birth
Source Mercy
Housing Midwest, Omaha, NE.
3Critical Issues in Population Geography
- More people are alive today than at any other
time in human history. - The worlds population increased at a faster rate
during the second half of the 20th century than
ever before. - Virtually all population growth today occurs in
less developed countries (LDCs)
4Key Population Issues
- Key Issues
- Where is the world's population distributed?
- Where has the world's population increased?
- Why is population increasing at different rates
in different countries? - 4. Why might the world face an overpopulation
problem?
5Population Distribution
- Key Issue 1 Where Is the World's Population
Distributed? - Population concentrations
- Sparsely populated regions
- Population density
6Distribution of World Population
- Population concentrations
- The four largest population clusters (2/3 of
worlds population) - 1. East Asia China, Japan, Korean Penn. (1/4)
- 2. South Asia India, Bangladesh, Pakistan, Sri
Lanka (1.4) - 3. Southeast Asia Indonesia, Indochina Penn.
(islands) - 4. Europe Western Europe, Eastern Europe (High
population of city dwellers) - Other population clusters
- 1. Northeastern United States
- 2. Southeastern Canada
- 3. Western Africa Half live in Nigeria
-
-
7Population Distribution
8World Population Distribution
World population is very unevenly distributed
across the Earths surface and it can be
compared to climate distribution.
9World Population Cartogram
This cartogram displays countries by the size of
their population rather than their land area.
(Only countries with 50 million or more people
are named.)
10(No Transcript)
11Population Distribution
- Sparsely populated regions
- -The ecumene permanent human settlement
- -People generally avoid
- Dry lands 20 of surface desert no H2O. Do
Contain natural resources though (oil) - Cold lands crops cant grow, frozen ground
- Wet lands rain heat flooding, nutrient
depletion - High lands steep and cold
12Expansion of the Ecumene 5000 B.C.A.D. 1900
The ecumene, or the portion of the Earth with
permanent human settlement, has expanded to
cover most of the worlds land area.
13World Population Distribution by Region
18002050
14Population Density
- Arithmetic Density the total number of people
divided by the total land area ( This measure is
also called population density.) Arithmetic
density enables geographers to make approximate
comparisons of the number of people trying to
live on a given piece of land in different
regions of the world. - There is no relationship between arithmetic
density and standard of living.
15Arithmetic Population Density
Arithmetic population density is the number of
people per total land area. The highest densities
are found in parts of Asia and Europe.
16Effect of Migration on Population Growth
- QA. How densely populated is the planet?
- 1st Western Europe, 433 people per sq. mile
- 2nd Caribbean, 417 people per sq. mile
- Least densely settled region is Oceania 10
people per sq. mile - United States is 78 people per sq. mile
- Q. Does high density in urbanized areas equal
environmental degradation????
17Population Densities, 2003
- Region Pop./Sq. Mile
- World 122 Caribbean 417
- More Developed Countries 61 South America 52
- Less Developed Countries 160 Asia 312
- Africa 74 Western Asia 112
- Sub-Saharan Africa 76 South Central Asia 376
- Northern Africa 57 Southeast Asia 313
- Western Africa 108 East Asia 334
- Eastern Africa 107 Europe 82
- Middle Africa 41 Northern Europe 141
- Southern Africa 49 Western Europe 433
- North America 42 Eastern Europe 41
- Latin America 68 Southern Europe 288
- Central America 150 Oceania 10
- Source Population Reference Bureau, 2003 World
Population Data
18Physiological Density
- A more meaningful population measure is by
looking at the number of people per area of a
certain type of land in a region. - The number of people supported by a unit of
arable land is called the physiological density. - Comparing physiological and arithmetic densities
helps geographers to understand the capacity of
the land to yield enough food for the needs of
people.
19Physiological Density
Physiological density is the number of people
per arable land area. This is good measure of
the relation between population and agricultural
resources in a society.
20Agriculture Density
- Two countries can have similar physiological
densities, but they may produce different amounts
of food because of different economic conditions.
Agriculture density is the ratio of the number of
farmers to the amount of arable land. - The Netherlands has a much higher physiological
density than does India but a lower agriculture
density. - Agriculture density is directly related to
standard of living the lower the agricultural
density, the higher the standard of living why?
21Measures of Density
22Distribution of World Population Growth
- Key Issue 2 Where has the Worlds Population
Increased? - Natural Increase the percentage by which a
population grows in a year - Crude birth rate (CBR) the number of births per
1,000 population - Crude death rate (CDR) the number of deaths per
1,000 population - Doubling time the number of years needed to
double a population
23World Population Growth19502010
Total world population increased from 2.5 to 6
billion in this half century. The natural
increase rate peaked in the early 1960s and has
declined since, but the number of people added
each year did not peak until 1990.
24World Population Growth, 17502150
Source United Nations, World Population
Prospects, The 1998 Revision and estimates by
the Population Reference Bureau.
http//www.youtube.com/watch?v9_9SutNmfFkfeature
BFlistULadYPZ59_AUcindex1
25Natural Increase
- QA When could world population stop growing?
- First one half million years the population
growth rate was about zero - 1700s modern era of population growth began
- Between 1850 and 1900, the annual growth rate
reached 0.5 percent - By the mid-1960s rate surged to 2.0 percent
- Dropped to 1.7 percent by the mid-1980s, and
declined to about 1.4 percent by 2000.
26Natural Increase Rates
The natural increase rate (NIR) is the
percentage growth or decline in the population of
a country per year (not including net migration).
Countries in Africa and Southwest Asia have the
highest current rates, while Russia and some
European countries have negative rates.
27Crude Birth Rates
The crude birth rate (CBR) is the total number
of births in a country per 1,000 population per
year. The lowest rates are in Europe, and the
highest rates are in Africa and several Asian
countries.
28Crude Death Rates
The crude death rate (CDR) is the total number of
deaths in a country per 1,000 population per
year. Because wealthy countries are in a late
stage of the demographic transition, they often
have a higher CDR than poorer countries.
29Population Growth through Natural Increase,
17752000
30Total Fertility Rates
The Total fertility rate (TFR) is the number of
children an average woman in a society will have
through her childbearing years. The lowest rates
are in Europe, and the highest are in Africa and
parts of the Middle East.
31Infant Mortality Rates
The infant mortality rate is the number of infant
deaths per 1,000 live births per year. The
highest infant mortality rates are found in some
of the poorest countries of Africa and Asia.
32World Infant Mortality Rates in Selected
Countries, 2000
Source Carl Haub and Diana Cornelius, 2000 World
Population Data Sheet (Washington, DC Population
Reference Bureau, 2000).
33Life Expectancy at birth
Life expectancy at birth is the average number of
years a newborn infant can expect to live. The
highest life expectancies are generally in the
wealthiest countries, and the lowest in the
poorest countries.
34Doubling Time
- Doubling Time of a population (years)
- 70 / Population Growth Rate ()
- ( 70 / 2.0 35 years )
- Rule of 70 determine how long it would take for
a population to double at its present growth
rate. - divide 70 by the populations annual growth rate
to determine the years needed to double the size
of the population.
35Human Population Doubling Time
36Why has the worlds population grown at such
different rates throughout history?
- 3 variables births, deaths, and migration
- Balancing Equation
- A. The difference between births and deaths in a
population produces the natural increase(or
decrease) of a population. - B. Net migration is the difference between the
number of persons entering a geographic area
(immigrants) and those leaving (emigrants) - C. Natural increase usually accounts for the
greatest amount of growth in a population,
especially within a short period of time. -
37Population increases at different rates
- Key Issue 3 Why is population increasing at
different rates in different countries? - The demographic transition model
- Population pyramids
- Countries in different stages of demographic
transition - Demographic transition and world population growth