Cities and sustainability reminder what is sustainability welcome

Cities and sustainability reminder: what is sustainability?

welcome 2 make up classes still needed This week - Wednesday or Friday? or, since we need to add another 90 minutes, we can add 15 minutes to the next 6 classes

Cities… ⁃ 3. 6 billion people of the 7. 0 billion world population live in urban areas, and this urban population is projected to increase to 6. 3 billion in 2050 (while the world population will be 9. 3 billion). ⁃ cities in the world account for between 71% and 76% of global carbon dioxide (CO 2) emissions

Let’s think together • Break into teams. • What are the indicators for a sustainable city? What are the questions that need to be asked? • Think: environmental, social, economic, governmental • Take notes, choose a rep, and report back to the class.

Beirut • 0. 8 square meters of public green space / person • WHO recommends a minimum of 9 square meters / person • Beirut is 50 times less than recommended

Sustainable city? Kennedy et al. (2007): a sustainable city can only be one for which the in ow of material and energy resources, and the disposal of wastes, do not exceed the capacity of the city’s surrounding environment. In other words, for achieving environmental sustainability urban consumption must match or be below what the natural environment — such as forests, soil and oceans — can provide, and the resulting pollutants must not overwhelm the environment’s ability to provide resources to humans and other members of the ecosystem.

• please see / read the readings provided on the blog

chapter 22

living in urban areas • Urbanization: the creation and growth of urban and suburban areas; measured as the % of people in a country, or in the world, living in such areas • Urban growth: rate of increase of urban populations • 1 st cities: 6, 000 years ago. … Today, ½ of the world’s population live in urban areas • growth by natural increase and by immigration, mostly from rural areas

4 major trends in urban population dynamics 1. Proportion of global population living in urban areas is increasing; could reach 66% by 2030; 88% of growth in already overcrowded and economically stressed cities 2. Numbers and sizes of urban areas are mushrooming. Every week: 1 million people. Megacities - cities w/ 10 people or more 3. Urban growth is much slower in more developed countries; more-developed at 75% urbanization - to reach 81% by 2030 4. Poverty is increasingly urbanized. 1 billion people in leesdeveloped countries live in slums

1609 …

some undesirable impacts of urban sprawl • Land biodiversity • • Water • • increased use and pollution of surface water and groundwater; increased runoff and flooding Energy, air and climate • • loss of cropland & loss and fragmentation of forests, grasslands, wetlands and wildlife habitat increased energy use and water; increased emissions of carbon dioxide and other air pollutants Economic effects • decline of downtown business districts; more unemployment in central cities

any advantages? • centers of development … • centers of services … • recycling may be more feasible; may preserve biodiversity … ; may save energy … • how?

any disadvantages • intense population pressure and high population densities • huge ecological footprints • • urban population occupy about 2% of the earth’s area but consume about 75% of its resource and produce 75% of the world’s climate changing carbon dioxide • http: //rprogress. org/index. htm - for your information [read the core case study of Curtiba, Brazil]

most cities • lack vegetation [and the vegetation could absorb air pollution give off oxygen, provide shade, reduce soil erosion, provide habitat] • have water problems [water demands increase; reservoirs and canals built; deeper wells drilled; depriving rural and wild areas, and depleting underground water supplies] • concentrate pollution and health problems [plus can increase spread of infectious diseases] • excessive noise [prolonged exposure to sound levels above 85 db. A] • affect local climates [warmer, rainier, foggier, cloudier than rural areas. why? generate more heat - create urban heat island] • cause light pollution [sea turtles…]

urban heat island

• What to do about slums / shanty-towns? • “Should squatters living in or near cities by given title to the land they live on? ”

Transportation? • • • Cities can grow outward or upward • outward with cheap gasoline, highways, plentiful land • US: 4. 6% of world’s population and ⅓ of the world’s vehicles; use 43% of the world’s gasoline motor vehicles • 1. 2 million deaths a year (3, 300/day); 50 million animals • congestion … outdoor air pollution reducing car usage • car sharing … bikes… mass transit rail… buses…

land-use planning • zoning: parcels of land are designated for certain uses • height restrictions; property tax; • Beirut: http: //www. executive-magazine. com/businessfinance/real-estate/higher-regulation

making cities sustainable? • walkability • mixed-use and diversity • quality urban design • smart transportation • — cities for people not for cars

major urban resource and env problems