FOUNDATIONS OF
GEOGRAPHY
The Science of Geography
geography from the Greek – geo and
graphy
It has both spatial perspective and temporal
perspective
The Study of Geography, cont
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Geographic Science is founded on five “themes”
location
region
place
movement
human-earth relationships
It is both a physical and social science
[see Fig 1.2: The content of geography]
(1) Cultural (Human) Geography
population; culture; ethnicity
(2) Physical Geography
meteorology; geomorphology
Both Subfields Study:
(1) Location
--- absolute and relative
(2) Characteristics of Places
--- physical landscape and cultural
landscape
(3) Spatial Distributions and Spatial
Patterns
Both Subfields Study:
(4) Spatial Interaction
links across the Earth surface
(5) Ever Changing Earth
(a dynamic system)
(6) Human Interactions With The Environment
Systems Theory / The Earth System
- The Earth is a system
- A system is a set of interrelated components /
factors existing to carry out a function
--- a system is open or it is closed
- A system is conceptualized according to its
components
Attempt to understand how these
variables relate / affect / impact
- state (level) and rate
Systems are dynamic, but are viewed
point-in-time… Man needs an Earth in
dynamic equilibrium
Systems are composed of “nested” subsystems
Earth is a Complex System
Complex systems are characterized by:
(1) strong (usually non-linear) interactions between
components;
(2) complex feedback loop that make it difficult to
distinguish cause from effect;
(3) significant time and space lags, discontinuities,
thresholds, and limits;
(4) the inability to simply “add up”(aggregate)
small-scale behavior to arrive at large-scale results
Earth Subsystems
(1) Atmosphere
(2) Lithosphere
(3) Hydrosphere
(4) Biosphere
Models and Systems
Many systems are too complex to understand as
they exist
… we create models in an attempt to
simplify
… we must be careful not to become
reductionist
Models may be:
(1) Physical
(2) Diagrammatic / Graphic
(3) Mathematical / Statistical / Computer
generated
(4) Conceptual (ex: mental maps)
Environment-Ecology-Ecosystem
Geography is interested in relationships of ManEnvironment / Spatial-Temporal
--- best studied through “impacts”
--- this is especially true for physical geography
and the physical environment
Environment
physical, cultural and social aspects of our
surroundings; affects our growth, way-of-life,
etc.
… romanticized, environment is:
(1) our “canvas”: Man-Land Relationship
(2) our “paints”: Natural Resources
(3) our “work-in-progress”: Cultural
Resources
Ecology
Ellen Swallow at M.I.T.
[have also heard the name Ernst Heinkel (latter
19th C) associated with coining this term]
Study of the relationships between organisms and
their physical environment
Ecosystem
Ecological system
Community of organisms and their relation to the
physical environment; a dynamic relationship
The Earth as a Planet: A Spherical Planet
We tend to think of the Earth as infinite
… obviously it cannot be
Unless we can circumvent light year distances, we
are limited to the planet that we have
Size and Shape of the Earth
Throughout history Man has speculated about
the Earth, its shape and our place in
“everything”
Earth Mother
cosmologic civilizations
universalizing religions
Pythagoras (540 B.C)
theorized Earth as a sphere
Eratosthenes (circa. 247 B.C)
Greek climate scheme
“proved” the Earth is round
Earth is an oblate spheroid
(ellipsoid of rotation)
7900 mi x 7927 mi
Movements of the Earth
The Earth has three basic movements:
(1) rotation turning of Earth on polar
axis
1o of arc every 4 min
1040 mph at Equator
0 mph at Poles
direction according to perspective
rotation, cont
We are not aware of rotational velocity:
(a) constant for all locations on Earth
(b) atmosphere rotates at same velocity
(c) no nearby objects for a frame of
reference of motion
Rotation gives us circle of illumination
Someday Earth rotation will stop
(2) revolution – elliptical Earth movement
around the sun
… Jan 3 at its perihelion
… July 4 at its aphelion
(3) galactic movement – movement of Earth, Sun
and Solar System around the center of the
Milky Way
Location and Time on Earth
- The ability of delineate location (absolute
location) is fundamental to spatial perspective
--- absolutely necessary for cause-and-effect;
for location-relationship; for compare-andcontrast studies
- Verbal communication of location must have
evolved early… particularly in the realm of the
personal mental map
- Assigning location quickly developed religious
and cosmological significance
- Historically, the most common representation
of location has been the map or the globe
- Because of the importance of map making, the
geographic field of cartography evolved
“the art that became a science”
Globes and Great Circles
- The globe represents that most perfect
representation of the Earth currently available
- Most important is that a globe correctly
represent the aspects of area and shape
--- because of this a globe allows illustration of
significant concepts (day-night; seasonal
change; etc)
- Globe has limitations:
(1) expense
(2) inconvenient shape
(3) lack of detail
Despite of their limitations globes serve as a good
starting point for explaining the concepts of
location… and this is what your text does
I.
Great Circle – and imaginary line on the
surface of the Earth that bisects the center
of the Earth (any other circle is a small
circle) [Fig 1.13]
--- represents largest circle possible on the
Earth
I. Great Circle, cont
--- the circumference of a great circle will be
the circumference of the Earth (?)
--- use:
(1) cuts Earth in ½ creating hemispheres
(2) each hemisphere will be the
circumference of the Earth (?)
(3) each is the shortest route of travel
around the Earth (great circle route)
Latitude and Longitude
A set of coordinate systems for deriving locations
on the Earth (Cartesian coordinates) [Fig 1.10]
II. Latitude
(1) latitude extends east-west and measure
angular distance north-south of the
Equator great circle
(2) are circles when viewed in entirety
(3) are parallel (equidistant)
(4) 1o of latitude equals approx 70 mi of
Earth surface distance
II.
Latitude, cont
… can further subdivide degrees
1 min = 1.2 mi. ; 1 sec = 102’
(5) vary greatly in length, but do so in an
orderly manner
(6) an unlimited number of parallels exist
(we use convenient numbers of them)
III. Longitude
- In order to pinpoint east-west location, we
must define a north-south measure
--- this can be done by defining an
arbitrary N.-S. reference line running
from pole-to-pole
… problem is, which one?
- 1884 Greenwich, England was designated as
the Prime Meridian (0o long)
III. Longitude, cont
- Locations measured in degrees, minutes,
seconds, east or west of Greenwich to a
maximum of 180o (International Date Line)
(1) meridians extend north-south and
measure distance east-west
(2) each is a ½ circle with Polar endpoints
(3) meridians are not parallel to each other
and converge at the Poles
[so distance of degrees, minutes, seconds
is latitude dependent]
III. Longitude, cont
(4) meridians always intersect at 90o
(5) an unlimited number of parallels exist
(we use convenient numbers of them)
With latitude and longitude we have effectively
created a universal, transferable grid
Longitude and Time
Time Zones
- Longitude has a special relationship in the
determination of time
- Problem of “local time” and “solar noon”
- 1884 the International Meridian Conference
established a system of time zones [Fig 1.15]
--- 24 zones of 15o longitude each,
representing an hour period
- From 1884 the Prime Meridian and every 15th
degree established the time for a time zone
7 ½o to either side of it
Maps and Map Projections
Maps are representations of the features / activities of
Earth having advantages and disadvantages for use
Advantages
(1) cheap to produce and transport
(2) easy to use and make for special requests
(3) ability to use at many scales
Disadvantages
cannot represent circular/spherical area on flat map
without distortion
… shape; area; distance; direction
… distortion greater as region represented gets
larger and/or gets further from the Equator
Map Essentials
Whatever the type of map, form of projection,
ultimate use, etc; all maps share some essential
features
(1) title - area and data depicted
(2) date - time frame of data depicted
(3) legend - key to symbolization used on map
(4) scale - statement of relationship of map
distance-to-Earth distance
Global Positioning Systems
GPS – Newest way available to determine
location on the Earth
--- takes advantage of orbiting satellites
to triangulate a requested position
--- initially developed for the military, now
potential utilization for any location /
activity
Modern Mapping Technology
Computer Mapping and Geographic Information
systems
Computer technology has revolutionized
cartography
Computer technology allows accumulation and
storage of unprecedented volumes of digital
form information for instant retrieval,
updating and perspective altering
Computer Mapping and Geographic Information systems,
cont
Geographic Information Systems (GIS)
- a computer-based technology that enters, analyzes,
manipulates and displays geographic information
- marriage of computer cartography and data-base
management
- potential to store/utilize massive amounts of data
- organized into layers of information – “overlays”
- super widespread applications
Downside to GIS is that accumulation of useable
data can be expensive and exhaustive
Remote Sensing of the Environment
- collection of data through a distance
- “remote sensor” is a mechanical device
accumulating information across a distance
- Utilizes visible light or radiant energy;
--- is “active” or “passive”;
--- can be photographic or nonphotographic