Global Perspectives
Thinking Geographically
What is Geography?
How do geographers describe Where things are?
Why is each point on earth unique?
Why are different places similar
What is Geography?
Geography is the scientific study of the location of people and activities, and natural phenomena across the Earth, and the reasons for their distribution
What is geography….?
Eratosthenes- An ancient Greek scholar coined the word from two Greek words, geo meaning earth and graphy meaning to write
Branches of Geography
Geography is divided broadly into two branches
Human Geography
Physical geography
Human Geography
Human geography studies where and why human activities are located as they are.
Physical Geography
Physical geography studies where and why natural forces occur as they do
Human and Environmental relations
Environmental determinism
Environmental possibilism
Regional Geography?
Region
A region is an area of Earth defined by one or more distinctive characteristics
Geography spatial Perspectives
Two simple questions:
Where and why there?
How Do Geographers Describe Where Things are?
Map
Contemporary tools (GIS, Remote Sensing)
Map
A map is a two-dimensional or flat-scale model of the earths surface, or a portion of it.
The science of mapmaking is called Cartography
Mental Maps
Two important uses of Map
A map serves two purposes:
A tool for storing reference materials
A tool for communicating geographic information
Types of Maps
Small scale
Large small
Contemporary tools
Geographic Information System (GIS)
Remote sensing
Remote Sensing
The acquisition of data about earth’s surface from a satellite orbiting earth or from other long-distance method
Geographic Information System
(GIS)
A computer-based system designed to collect, store, integrate, manipulate, analyze & display data in a spatially referenced environment.
GIS
The ‘Why’ of geography??
Why each point on the earth surface is unique?
Why different places are similar?
Two basic concepts help geographers to explain why each point on earth is unique:
Place: Unique location of a feature
Regions: Areas of unique characteristics
Place : Unique location of a feature
Geographers identify the location of something in four ways by
Place-name
Site
Situation
location
Place-name
Geographers call the name given to a portion of Earth’s surface its TOPONYM
Site
Site is the physical characteristics of a place
Climate
Water sources
Soil
Vegetation
Situation
It is the location of a place relative to other places
Location
There are two general types of locational information:
Relative location and
Absolute location.
Relative location defines a place in relationship to other places
Absolute Location
Absolute location is also known as mathematical location.
The use of coordinate systems
The most common coordinate systems on maps are Latitudes and Longitudes
Longitudes and Latitudes
Used to identify the location of features on the earth’s surface
They are measured in degrees, minutes and seconds
Latitudes and Longitudes
Realms and Regions
A region is an area of Earth defined by one or more distinctive characteristics
A realm is a much larger region.
Properties of Regions
Area
Boundaries
Location
Homogeneity
Types of Regions
There are three types of regions namely;
Formal
Functional
Vernacular
Formal Region
Formal region is also called a uniform region or a homogeneous region.
Functional Region
Functional region also called a nodal region
It is an area organized around a node or focal point.
Formed by the areal extent of the activities that define them
Vernacular Region
Also referred to as perceptual region, a place that people believe exists as part of their cultural identity.
These regions emerge from people’s informal perception of place, rather than from scientific models.
Spatial interactions and organization
Geographers try to understand why people and activities are distributed across space as they are.
Three main properties of distribution across Earth
Density
Concentration
Pattern
Density
The frequency with which something occurs in space.
Types of density
Arithmetic density is the total number of objects in an area.
Physiological density: is the number of persons per unit area suitable for agriculture
Concentration
The extent of a feature’s spread over space
Clustered objects in an area are close together
Dispersed objects are far apart
Patterns
The ways in which features are organized. Some features are organized geometrically, others are distributed irregularly
Physical setting
Continental drift
Alfred Wegener (1880-1930), a German meteorologist and geologist, was the first person to propose the theory of continental drift.
Pangaea
200 million years ago the continents were originally joined together, forming a large super continent called Pangaea, meaning "All-earth".
The southern part of this supercontinent was Gondwana of which Africa formed the core
Plate tectonic and continental drift
http://www.youtube.com/watch?v=Bf4iJvrAv-M
Evidence of continental drift
Glossopteris, a fern, was found on the continents of South America, Africa, India, and Australia
Rock sequences in South America, Africa, India, Antarctica, and Australia show remarkable similarities
The rift valley in Africa, for example, demarcates the zones where plate movement occurs.
Earth’s safest zones
Russia, Europe, Africa and Australia are relatively safe to crustal instability
North and South America, Asia are risky areas
Major population cluster
The three world population cluster (3.7 million)
East Asia,
South Asia, and
Europe
Other population clusters
Eastern United States
Nigeria in West Africa
Patterns of development
Causes of the contrast
Climate
Cultural Heritage
Colonial exploitation
Neocolonialism
Distribution of accessible natural resources
Relative location
Quiz Area
What is geography?
How do geographers describe Where things are located?
Evidence of continental drift
What is developments and what are the causes of global and regional contrasts in development
The physical and cultural map of Africa
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