Population and Global ResourcesPopulation and Global Resources

OutlineOutline

The need for population projections Population Projection Methods Global Statistics –

Population Energy Water

The need for population projections Population Projection Methods Global Statistics –

Population Energy Water

Population ProjectionsPopulation Projections

Needed by engineers and planners for the design of facilities and infrastructure (roads, mass transit, water supply, wastewater collection and treatment, schools, hospitals...)

Population projections rely on ________ population growth (trend line extrapolation) Models with various levels of sophistication based on

estimates of fertility and mortality

Needed by engineers and planners for the design of facilities and infrastructure (roads, mass transit, water supply, wastewater collection and treatment, schools, hospitals...)

Population projections rely on ________ population growth (trend line extrapolation) Models with various levels of sophistication based on

estimates of fertility and mortality

Historic

Population Projection MethodsPopulation Projection Methods

constant rate of growth

proportional to the population

Arithmetic progression Constant slope (___________________) Least squares regression line

Geometric progression The ratio between successive terms is constant Rate of growth is ________________________

at the beginning of each time period

Arithmetic progression Constant slope (___________________) Least squares regression line

Geometric progression The ratio between successive terms is constant Rate of growth is ________________________

at the beginning of each time period

Geometric ModelGeometric Model

Difference Equation

WithWith N(0) = 10, r = 0.2 [1/t], N(0) = 10, r = 0.2 [1/t], t = 0.5 [t]t = 0.5 [t]

N(1) = 12.1N(1) = 12.1

N(2) = 14.6N(2) = 14.6

N(10) = 67.3N(10) = 67.3

Geometric progressionGeometric progression

Future population

Present population

Population growth

020406080

0 2 4 6 8 10time

popu

latio

n N when delta t is 0.5

N t t N t N t r t( ) ( ) ( )

Geometric ModelGeometric Model

The results of the difference equation are a function of the _______used

The results of the difference equation are a function of the _______used

002020404060608080

00 22 44 66 88 1010timetime

popu

lati

onpo

pula

tion

1010

tt

5522 11

0.50.50.10.1

time step

Exponential growth modelExponential growth model

no resource limitationsno competition among individuals

Similar to geometric progression Specific rate of growth is constant (growth rate

per individual is independent of the population density)

Limit of the geometric growth model where the time interval goes to zero

Under what conditions might this occur? Frequently observed with new populations ___________________________________ ___________________________________

Similar to geometric progression Specific rate of growth is constant (growth rate

per individual is independent of the population density)

Limit of the geometric growth model where the time interval goes to zero

Under what conditions might this occur? Frequently observed with new populations ___________________________________ ___________________________________

Exponential Growth Model: Derivation

Exponential Growth Model: Derivation

Specific rate of growth is constant

N = size of the populationN0 = initial size of the populationt = timet0 = initial timer = growth rate

rdtN

dN rdtN

dN

dNN

rdtN

N t

t

t

( )

( )

0 0

XZY z

dNNdt

rNormalized by the total amount

N t dt N t N t rdt( ) ( ) ( )

N t dt N tN t

rdt( ) ( )

( )

Geometric Model tdN

growth rate

Exponential Growth Model Equations

Exponential Growth Model Equations

00lnln rtrtNtN 00lnln rtrtNtN

)(0

ln 0ttrN

tN

)(0

ln 0ttrN

tN

0

0ln rtrtN

tN

0

0ln rtrtN

tN

e

ttr

N

tN )( 0

0

e

ttr

N

tN )( 0

0

bmxy bmxy

N t Nr t t

eaf af 0 0( )

Linearized form: the Linearized form: the slope (m) will be the slope (m) will be the _______ _____._______ _____.

Geometric/Exponential Model Comparison

Geometric/Exponential Model Comparison

t 1r 0.2N(0) 10t(0) 0

0

20

40

60

80

0 2 4 6 8 10time

popu

lati

onN when delta t is 1Exponential Model

ManhattanManhattan

Manhattan PopulationManhattan Population

00

10000001000000

20000002000000

30000003000000

16001600 17001700 18001800 19001900 20002000

yearyear

popu

lati

onpo

pula

tion

Brooklyn Bridge Completed: 1883  

What resources limited the growth rate?

Component methodComponent method

fertility and mortality

Divide base population into age, gender, economic, ethnic components

Apply ___________________ rates to each component

Assume trends for future immigration and emigration and apply fertility and mortality rates to these groups as well

Divide base population into age, gender, economic, ethnic components

Apply ___________________ rates to each component

Assume trends for future immigration and emigration and apply fertility and mortality rates to these groups as well

Population Pyramids(by country)

Population Pyramids(by country)

Application of component method to nations

Application of component method to nations

http://www.census.gov/ipc/www/idbpyr.html

Global StatisticsGlobal Statistics

Population growth Resource Utilization

Energy Vehicles Water

Population growth Resource Utilization

Energy Vehicles Water

Urban PopulationUrban Population

0

500

1000

1500

2000

2500

3000

1975 1980 1985 1990 1995

year

mil

lion

s

West Asia

North America

Latin America and theCaribbean

Europe and Central Asia

Asia and the Pacific

Africa

0

500

1000

1500

2000

2500

3000

3500

1975 1980 1985 1990 1995

year

mil

lion

s

Rural

Urban

Urban population is overtaking rural population

Urban and Developed World footprints

The Footprint of the Developed World

The Footprint of the Developed World

North America, Europe and parts of East Asia consume immense (unsustainable) quantities of energy and raw materials, and produce high volumes of wastes and polluting emissions…

that cause environmental damage on a global scale (notably climate change) and widespread pollution and disruption of ecosystems, often in countries far removed from the site of consumption.

Wealthy industrialized countries control pollution locally but the wider-scale impacts (apart from ozone depletion) have yet to be tackled effectively.

North America, Europe and parts of East Asia consume immense (unsustainable) quantities of energy and raw materials, and produce high volumes of wastes and polluting emissions…

that cause environmental damage on a global scale (notably climate change) and widespread pollution and disruption of ecosystems, often in countries far removed from the site of consumption.

Wealthy industrialized countries control pollution locally but the wider-scale impacts (apart from ozone depletion) have yet to be tackled effectively.

Energy ConsumptionEnergy Consumption

0 50 100 150 200

Africa

Asia and the Pacific

Europe and Central Asia

Latin America and theCaribbean

North America

West Asia

Total Energy Consumption (Pj)

0 100 200 300 400

Per Capita Energy Consumption (Gj)

1015 P "Peta"

1012 T "Tera"

109 G "Giga"

106 M"Mega"

103 k "kilo"

1015 P "Peta"

1012 T "Tera"

109 G "Giga"

106 M"Mega"

103 k "kilo"

How much does How much does a Gj of electricity a Gj of electricity cost?cost?

Energy conversions

What are the What are the energy costs per energy costs per person?person?

Motor VehiclesMotor Vehicles

Transport now accounts for _____ of world energy use _____ of the world's oil production

motor vehicles account for nearly ___ % of all transport-related energy

Transport is/causes a major contributor to greenhouse gas

emissions urban air pollution substantial land use habitat degradation and fragmentation

Transport now accounts for _____ of world energy use _____ of the world's oil production

motor vehicles account for nearly ___ % of all transport-related energy

Transport is/causes a major contributor to greenhouse gas

emissions urban air pollution substantial land use habitat degradation and fragmentation

0

100

200

300

400

500

600

700

800

198

0

199

0

199

6

year

mill

ion

s

West Asia

North America

Latin America andthe Caribbean

Europe andCentral Asia

Asia and thePacific

Africa

1/41/41/21/2

8080

FreshwaterFreshwater

The declining state of the world's freshwater resources, in terms of quantity and quality, may prove to be the dominant issue on the environment and development agenda of the coming century

About 20 % of the world's population lacks access to safe drinking water and about 50 % lacks adequate sanitation

Worldwide, polluted water is estimated to affect the health of about 1.2 billion people and to contribute to the death of about 15 million children under five every year (ICWE 1992).

The declining state of the world's freshwater resources, in terms of quantity and quality, may prove to be the dominant issue on the environment and development agenda of the coming century

About 20 % of the world's population lacks access to safe drinking water and about 50 % lacks adequate sanitation

Worldwide, polluted water is estimated to affect the health of about 1.2 billion people and to contribute to the death of about 15 million children under five every year (ICWE 1992).

Measures of PovertyMeasures of Poverty

0 200 400 600 800 1000 1200 1400

malnourished children

people not expectedto survive to age 40

people lackinghealth services

illiterate adults

people lackingsafe water

people who areincome-poor

millions

Water Supply – Global Coverage in 2000

Water Supply – Global Coverage in 2000

0 – 25%26 – 50%51 – 75%76 – 90%91 – 100%Missing data

What do the countries with the poorest coverage share?

Water Supply Coverage for Developing Countries

Water Supply Coverage for Developing Countries

24%

49%66%

47%

38%

32%

19%

31%

19% 15% 22%38%

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Africa Asia LA & C Total

No access

Other access

Householdconnection

Water Supply in the Largest Cities

Water Supply in the Largest Cities

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Africa

Asia

LA &

C

N. Am

er.

Ocean

ia

Europ

e

Unserved

Others

Borehole or handpump

Public tap

House connection oryard tap

Mean percentage of population with each type of serviceMean percentage of population with each type of service

What are the implications of being “unserved?”

Treated Urban WastewaterTreated Urban Wastewater

0%

35%

14%

66%

90%

no data0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Africa Asia LA & C N.Amer.

Oceania Europe

Goals for Sustainable Development Related to Water

Goals for Sustainable Development Related to Water

Ensure the adequate supply and efficient use of water for agricultural, industrial, urban and rural development

Ensure adequate access of the poor majority to clean water for domestic use and small scale agriculture

Ensure adequate protection of watersheds, aquifers and freshwater ecosystems and resources

Ensure the adequate supply and efficient use of water for agricultural, industrial, urban and rural development

Ensure adequate access of the poor majority to clean water for domestic use and small scale agriculture

Ensure adequate protection of watersheds, aquifers and freshwater ecosystems and resources

economic

social

environmental

The ChallengeThe Challenge

All population growth is expected to occur in developing nations

Rural population is expected to stabilize at around 3.2 billion (from 2.97 billion today)

The growing population will settle in urban areas. The challenge is to provided the basic

infrastructure required by nearly 2 billion new urban residents in the developing world by 2025.

All population growth is expected to occur in developing nations

Rural population is expected to stabilize at around 3.2 billion (from 2.97 billion today)

The growing population will settle in urban areas. The challenge is to provided the basic

infrastructure required by nearly 2 billion new urban residents in the developing world by 2025.

SummarySummary

Global Human Population Resource Utilization

Unsustainable Wealthy industrialized countries cause environmental

damage on a global scale Unjust

Water Challenge of providing clean drinking water and treating

wastewater as population grows, resources are stretched, and global climate changes

Energy…Our information technology revolution will fail if it continues to run on coal and oil

Global Human Population Resource Utilization

Unsustainable Wealthy industrialized countries cause environmental

damage on a global scale Unjust

Water Challenge of providing clean drinking water and treating

wastewater as population grows, resources are stretched, and global climate changes

Energy…Our information technology revolution will fail if it continues to run on coal and oil

GEO-2000 regions GEO-2000 regions

Energy CostsEnergy Costs

8$0.10 $2.8 10 $283600 1000hr kW

kW hr s W J GJ

-´× × = =

×

If all of our energy use was electricity our annual energy cost would be

350 $28$9,700 /

GJperson

Capita GJ× =

•Electricity is the most expensive form of energy.

•We pay for our energy at many different places.

Taxes, gasoline, firewood, anything we purchase!