1. Chapter 13 Urban Patterns
Key Issue 1
Where Have Urban Areas Grown?

2. Urbanization
Urban geographers are concerned with the global distribution of urban settlements as well as the distribution of people and activities within urban areas.
The first cities emerged thousands of years ago but, as recently as 1800, only 3% of the world’s population lived in cities.
Today nearly half of the world’s people live in cities. About three-quarters of people living in MDCs live in urban areas compared to about two-fifths in LDCs, although urbanization in Latin America is comparable to MDCs.
Urban geography deals with all aspects of cities, including their historical development, spatial development, interaction with surrounding regions, and role in the world economic system.
Urbanization is the process by which the population of cities grows, both in numbers and percentage.

3. Defining Urban Settlements
In the 1930s Louis Wirth, an urban geographer, defined a city as a permanent settlement that has a large size, high population density, and socially heterogeneous people.
Urban settlements today can be physically defined by legal boundary, as continuously built-up area, and as a functional area.
Urbanism dates back almost to the time of sedentary agriculture but developed very slowly.
In Europe, Athens and Rome were important urban areas in the ancient world, but urban life did not thrive in the early Middle Ages. Cities developed in Asia and the Americas at this time.
The great European cities, such as Madrid, Prague, Vienna, and Amsterdam, emerged during the 1400s. The Spanish developed colonial cities in the Americas during the 1500s.
It was during the 18th century in association with the Industrial Revolution that urbanism really took off on a global scale.

4. Defining Urban Settlements cont.
In MDCs a large percentage of people living in urban areas is one measure of a country’s level of development.
Urbanization over the last 200 years in MDCs is a consequence of rural to urban migration to work in factories and services.
LDCs have also experienced more recent rural to urban migration in search of economic activities in cities. Unfortunately urban jobs are much less available in LDCs.
MDCs have higher percentages of urban dwellers, but LDCs have larger numbers of people living in urban areas.
Seven of the ten most populous cities, including Mexico City, Sao Paulo, and Seoul. These are megacities and are characterized by chaotic growth, pollution, and poverty.

5. Physical Definitions of Urban Settlements
Virtually all countries have a political system that recognizes cities as legal entities with fixed boundaries.
In the U.S. a city that is surrounded by suburbs is sometimes called a central city.
The central city and surrounding suburbs are together called an urbanized area.
The U.S. Census Bureau defines the functional areas of cities for political and economic purposes.
A Metropolitan Statistical Area (MSA) includes a central city of at least 50,000 with high density adjacent counties where the majority of inhabitants work in non-agricultural jobs.
The census has also designated smaller urban areas as micropolitan statistical areas. These include an urbanized area of between 10,000 and 50,000 inhabitants and adjacent counties tied to the city.
A Consolidated Metropolitan Statistical Area (CMSA) consists of two adjacent MSAs with overlapping commuter patterns such as the Washington-Baltimore CMSA.
Within a CMSA, an MSA that exceeds one million people may be classified as a Primary Metropolitan Statistical Area (PMSA). The metropolitan areas of the northeastern U.S. now form one continuous urban complex or megalopolis.