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 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

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  : 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  the number of urban areas with 1 million or more people will increase from 400 to Urban growth is slower in more developed countries 4. Poverty is becoming increasingly urbanized, especially in less developed countries Trends in Urbanization

Regional Trends in Urbanization

Global Differences in Urbanization 1.More Developed Countries  Examples: New York City and London  Arose in 1800’s and 1900’s  Reached current size mid century  Experienced slow growth or decline 2.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  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 2.Urban populations consume more food, energy, durable goods than rural populations 3.In China---  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.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. 2.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  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 CO 2 )  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