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Cities are an environmental abomination. . . Right?. “ The growth of cities will be the single largest influence on development in the 21st century. ” UN, 1996, State of World Population. Largest urban areas.
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“The growth of cities will be the single largest influence on development in the 21st century.” • UN, 1996, State of World Population
Largest urban areas • 1. Tokyo, Japan - 28,025,000 2. Mexico City, Mexico - 18,131,000 3. Mumbai, India - 18,042,000 4. Sáo Paulo, Brazil - 17, 711,000 5. New York City, USA - 16,626,000 6. Shanghai, China - 14,173,000 7. Lagos, Nigeria - 13,488,000 8. Los Angeles, USA - 13,129,000 9. Calcutta, India - 12,900,000 10. Buenos Aires, Argentina - 12,431,000
Air quality • Magnitogorosk, RU • Hyderabad, IND
Air quality • Primary and secondary air pollution • Primary: directly emitted • Particulate matter: pm10 and pm5 • Lead • Secondary: forms in atmosphere • Ground level ozone
Impermeable surfaces • Don’t allow water to sink into the ground • Instead, water runs off quickly to storm drains • Overwhelms sewage treatment plants, OR • Goes directly to nearby water bodies
Cities influence climate • Urban heat island effect • Roads, buildings, other infrastructure replace vegetation • Absorb solar energy during day, radiate heat at night • Roofs, roads can be 50-90 deg. F hotter than air temperature!
Major Urban Problems in U.S. • Deteriorating services • Aging infrastructures • Budget crunches from lost tax revenues as businesses and affluent people leave • Rising poverty with violence, drugs, decay • Urban sprawl - growth of low-density development on edges of cities and towns • 9 consequences of “bad growth”
75% of the US population live in urban areas occupying 3% of the country’s land area
Urban Resource and Environmental Problems • Destruction of plant life - what is $ value? • Cities produce little of own food • Urban heat island effect • Water supply and flooding problems • High pollution exposure
Urban Resource & Environmental Problems • Excessive noise exposure health effects • Hearing loss, hypertension, muscle tension, migraines, headaches, higher cholesterol levels, gastric ulcers, irritability, insomnia, psychological disorders, aggression
Urban Resource & Environmental Problems • Beneficial effects: • education • social services • medical care • Harmful effects • infectious disease spread • high density population • inadequate drinking and sewage system • physical injuries • pollution exposure • Urban Sprawl
Transportation • Greater use of mass transit and less use of private automobiles • Much more walking in some cities
transportation • Energy efficiency of different forms • Btus per person mile • Vanpool 1322 • Eff. Hybrid 1659 • Commuter rail 2996 • Cars 3512 • Air 3261
Fighting obesity • City dwellers less likely to be obese • St. John Newfoundland 36% • Toronto 16% • Vancouver 12% • New York City 20%
Alternatives to cities • Suburbs • Developed during 20th century • People wanted space • Loans, returning veterans • Transportation: cars made living in one place, working in another possible • Westchester cty, NY: world’s first large-scale suburban development
Sprawl development • Spreading outward of city and suburbs • Low-density development • Single family homes, large lots • Auto dependent development • Long distances to work
Zoning • Laws that regulate land use in a city or town are zoning laws (or regulations).
Smart Growth • A new development paradigm • Restoring center cities or older suburbs • Transit and pedestrian oriented • Mix of housing, retail, entertainment, other uses
Urban considerations • Energy use • Transportation • Cars vs. bikes vs pedestrian vs mass transit • Living space • Recycling • Lack of green space
Urban Sprawl: Causes & Effects • (1) Automobiles and Highway Construction • (2) Living Costs • (3) Urban Blight • (4) Government Policies
(1) Automobiles and Highway Construction • 1950’s: the Interstate Highway System • Commuting • Work in the city and live in the suburbs • Best of both worlds!
(2) Living Costs • The American Dream • More Land • Larger House • Privacy • Lower taxes • Overall, higher standard of living Levittown • Excludes low income families
(3) Urban Blight • The degradation of the built and social environments of the city that often accompanies the accelerated migration to the suburbs • A positive feedback loop
(3) Urban Blight • People leaving cities • Shrinking tax revenues • City still must provide: police, fire, trash, sewage, public transportation, and social services • Cities reduce services • Crime increases • Infrastructure deteriorates • Built environment declines
(3) Urban Blight • Suburban office parks • Suburb to suburb commuting • Can’t provide public transportation b/c too spread out • Commute around cities instead of through them • No need to go to the stores in a city
(3) Urban Blight • Contributed to Racial Segregation • “White Flight” • Generated a disparity of opportunity • Suburban Property tax revenues allow for better schools • Example: Busing in Boston 1974