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 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

What’s bad about cities?

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

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!

What’s good about cities?

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%

City town suburb rural Energy consumption- quad. BTU 4. 02 Per household Million BTU 85.3 Per household member 33.7 town 1.94 102.3 39.7 suburb 2.46 108.6 40.3 rural 2.13 95.1 37.8

Sao Paolo Brazil, with much smaller eco footprint than Brazil as a whole

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

Calgary, Alberta

Strip malls

Smart Growth A new development paradigm Restoring center cities or older suburbs Transit and pedestrian oriented Mix of housing, retail, entertainment, other uses

Energy use Transportation Cars vs. bikes vs pedestrian vs mass transit Living space Recycling Lack of green space