Download Urbanization

Urbanization
MEGACITIES ARE MAJOR GLOBAL RISK AREAS. DUE TO
HIGHEST CONCENTRATION OF PEOPLE AND EXTREME
DYNAMICS, THEY ARE PARTICULARLY PRONE TO
SUPPLY CRISES, SOCIAL DISORGANIZATION, POLITICAL
CONFLICTS AND NATURAL DISASTERS. THEIR
VULNERABILITY CAN BE HIGH.
Urbanization
What is Urbanization?
1.The growth of cities, brought about by a
population shift from rural and small
communities, to larger ones, and the
change from a largely agricultural
economy to an industrial one.
2.Results in the development of cities and
towns on formally agricultural or natural
lands.
Vocabulary
http://www.megacities.uni-koeln.de/documentation/
1. Urbanization: creation & growth of urban & suburban
centers
2. Megacity: cities with 10 million or more people
 Currently 18 worldwide
3. Hypercity: city with 20 million or more people
 Tokyo has 32 million
 5 largest cities are destined to become hypercities
Tokyo Aerial Night View
Trends in Urbanization
1. Throughout human history, the human population has lived
in a rural lifestyle, dependent on agriculture and hunting for
survival.
 1900: average population of world’s largest cities ~ 700,000
 2009: average population of world’s largest cities ~ 6 million
 1850-2009: percent of people living in urban areas increased from
2% to 50%
 Majority of growth occurred in already overcrowded cities in less
developed countries
2. The numbers and sizes of urban areas are increasing
 2008-2015 the number of urban areas with 1 million or more people
will increase from 400 to 564
3. Urban growth is slower in more developed countries
4. Poverty is becoming increasingly urbanized, especially in
less developed countries
Regional Trends in Urbanization
Global Differences in Urbanization
1.
More Developed Countries
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2.
Examples: New York City and London
Arose in 1800’s and 1900’s
Reached current size mid century
Experienced slow growth or decline
Less Developed Countries
 Example: Mexico City
 Grew rapidly between 1950 and 1980
 Growing more slowly now
3. Asian and African cities are experiencing rapid growth
& now projected to continue growing
Sao Paulo: Model Ecocity
People are pulled to cities
in search of
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Jobs
Food
Housing
Educational opportunities
Better health care
Entertainment
When there isn’t enough
housing, jobs, food, money,
etc, people may turn to
shantytowns
Shantytown is an informal
settlement
 Result of urban poverty
 Often exploited by the
government
Size
1. Megacity: cities with 10 million or more people

currently 18 worldwide
2. Hypercity: city with 20 million or more people
 Tokyo, Japan is largest city in the world with 32
million
 By 2015, the 5 largest cities in the world are destined
to become hypercities
 Tokyo, Japan; Mumbai and Delhi in India; Dhaka,
Bangladesh; Sao Paulo, Brazil, and Lagos, Nigeria
3. Megalopolis: Forms as urban sprawl occurs;
separate urban areas tend to merge
 EX: Boston-New York-Washington DC (about 500
mile long urban area
United States: Population Shifting from
Rural to Urban Areas
1. People migrated from rural to large, central
cities
2. Many people migrated from large central cities,
to smaller cities and suburbs
3. Many people migrated from North and East to
South and West
4. Since 1970’s & 1990’s, some people have
migrated from cities and suburbs to developed
areas outside of suburbs
Environmental Problems
with Urban Sprawl
1. Lack of mass transit
2. Decreased energy
efficiency
3. Increased traffic
congestion
4. Destroys prime
cropland
Consumption Patterns of Urban
Centers
1.
People in Urban area have different consumption
patterns than rural people
Urban populations consume more food, energy,
durable goods than rural populations
In China---
2.
3.
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In the 1970’s, urban population consumed 2x as much pork as rural
populations who were raising pigs
In 1990’s, urban Chinese household was 2X more likely to have a TV,
and 8X more likely to have a washing machine, and 25X more likely
to have a refrigerator than rural residents
Per capita consumption of coal in towns & cities is 3X the
consumption o rate in rural areas
Consumption
and Income
1.
2.
As income grows, consumers in lower income countries
shift their food purchases away from carbohydrate-rich
staple foods toward more expensive sources of calories,
such as meat and dairy products.
Among developing countries with a large share of rural
population and rapid rates of urbanization, urbanization is
expected to significantly alter consumers' diets with a
greater consumption of meats, fruit, vegetables, and
processed food products.
Advantages of Urbanization
1. Economic centers for
 Development, innovation,
education, technological
advancements, jobs
 Industry, commerce,
transportation
2. Urban residents have
 Lower infant mortality rate
 Lower fertility rates
3. Environmental
 Recycling more available
 Preserve biodiversity
 Save energy if residents
have access to public
transportation
Disadvantages of Urbanization
1. High population density makes environment unstable
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Water sources overloaded with pollutants
Public transportation is near capacity
Area landfills are full
Huge ecological footprint
 Consume 75% of resources
 Produce 75% of greenhouse gases
 High level of waste produced due to high consumption of food, energy,
water, minerals, etc
 Most cities lack vegetation (which absorbs CO2)
 Spread of infectious disease increases (density dependent)
 Noise pollution can cause hearing loss
 Light pollution
Urban Heat
Islands
1. Tendency for a city or town to
remain warmer than its
surroundings, by as much as 10 °F
or more
 caused mostly by the lack of
vegetation and soil moisture
 sunlight is absorbed by manmade
structures -- roads, parking lots,
and buildings
 With little or no water to evaporate,
the sunlight's energy goes into
raising the temperature of those
surfaces and the air in contact with
them
Effects of Light Pollution
1. Plants must be able to
anticipate seasons
 Plants need to know when to
produce flowers so that fruit and
seed development can be
accomplished before the next
winter arrives
 Plants need to be able to detect
the difference between one
season and another in order to
flower at the correct time of year
 Plants may flower too soon or not
at all
2. Light pollution at night can also
disrupt circadian rhythms o
animal pollinators