World Population
World Population Distribution
China
Canada
India
USA
Indonesia
Other
World Population Distribution II
Where we live - global population densities.Density is indicated by the intensity of colour.
World Population
• When human population was small, our impact on world systems was fairly insignificant.
• Population numbers now have tremendous implications for the planet in terms of resource use, pollution and impact on the physical landscape.
• The effects on a per capita basis are greatest in the more developed countries.
The Census
The Census• Population study depends on
accurate counts. Fortunately, nearly every country attempts to do this regularly.
• This count is called a census and it is is conducted every 10 years. In Canada we count numbers every 5 years.
• Countries gather considerable information about their people, including demographic and social characteristics.
• The 2011 Census data will be available in February 2012. In the meantime, lets look at the data from 2006.
http://www12.statcan.ca/census-recensement/2006/dp-pd/92-596/P1-2.cfm?Lang=eng&T=PR&PRCODE=01&GEOCODE=01&GEOLVL=PR&TID=0
The Census
• Economic & population data is made available to those who wish it.
• Businesses and governments find this data invaluable.
The Census
• Businesses use census data to determine particular markets and identify sources of labour.
• Governments use census data to plan the delivery of services, plan taxation measures, and to allocate political representation by population.
Vital Statistics
• Between each census, governments continue to monitor demographic information, keeping track of– Births
– Deaths
– Immigration
– Emigration
NO NUMBERS…
BIRTH RATE
Number of births per 1000 people
Ex. Canada:390 000 births/yr ÷ 30 000 000 Pop. X 1000 =
13
Birth Rates
• Birth rates vary enormously from country to country.
0
5
10
15
20
25
Canada World DevelopedWorld
DevelopingWorld
Births per 1000
1998 Birth Rates
DEATH RATE
Number of deaths per 1000 people
210 000 deaths/yr ÷ 30 000 000 x 1000 =
7
Death Rates
• Births give only one part of the story. • Population numbers must also consider deaths. • Like births, it is calculated per 1000 population.
0
2
4
6
8
10
12
Canada World DevelopingWorld
DevelopedWorld
Deaths per 1000
NATURAL INCREASE
BIRTH RATE – DEATH RATE:X
How do we turn that into a %?X ÷ 1000 = .00_.00_ x 100 (out of 100%, right?) = ._%
IMMIGRATION RATE
Number of immigrants per 1000 people ofCanada’s population.7
Number of population to live elsewhere per1000 people2
EMIGRATION RATE
NET MIGRATION
= IMMIGRATION RATE – EMIGRATION RATE = 7 – 2= 5 (5/1000 or .5%)
Population Growth
POPULATION GROWTH!
ALL FOUR FACTORS OF POPULATIONCONTRIBUTE TO THE RATE AT WHICH ACOUNTRY’S POPULATION GROWS.
= NATURAL INCREASE + NET MIGRATION RATE=6 + 5=11 (11/1000 or 1.1%)
Population Pyramids
Population Pyramids• One of the most useful ways of showing
population structure is through an age-sex graph called a population pyramid.
• Population Pyramids are really two sets of bar graphs, side by side.
• Each bar represents a cohort - a group fitting within a specific age range.
Population Pyramids• One of the most useful ways of showing
population structure is through an age-sex graph called a population pyramid.
http://www.statcan.gc.ca/access_acces/alternative_alternatif.action?l=eng&k=95&loc=http://www12.statcan.gc.ca/census-recensement/2006/as-sa/97-551/vignettes/cda06pymd.swf
http://www.footwork.com/pyramids.asp
Dependency Load• Assumption that children (under 15) and older adults
(over 65) are not working and must be supported by the working population. The proportion of the population that must be supported is called, the dependency load. What is Canada’s current dependency load (add children and older adults). It’s 31.2%
• What are the effects of a high dependency load?– Education– Housing– Healthcare
– Old-Age Homes
Dependency Load
• Niger in north Africa, like many developing countries, has a high dependency load at 52% (49 % children!!! and only 3% older people). What does this tell you?
• Does our future looking friendly with the Baby Boom generation turning 65 (2011-31)?
http://www.footwork.com/pyramids.asp
Doubling Time• The difference between the birth rate and the death
rate has huge implications for population growth or shrinkage.
• The following equation can be used to estimate the number of years it will take for a population to double.
• This uses the “rule of 70”, which takes this figure as representing a generation’s lifetime.
70 ÷ % rate of growth of population years for = population to double
Doubling Time
• Marked differences exist between countries in terms of doubling times.
• Some developed countries have shrinking populations.
• Some of the least developed countries have frighteningly short doubling times.
Doubling Time• Immigration & emigration should also be
considered. • If a population is “closed” there is little to no
in or out migration. • Some countries have significant movement
and are described as “open”.