Basic Tools and Methods of Human Geographers

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Basic Tools and Methods of Human Geographers

• Observation
• Information must be collected and data recorded
• Methods
• Fieldwork
• Use of scientific instruments
• Laboratory experiments
• Archival searches
• Remote sensing
• Aerial photography or satellite imagery designed
  to record data on visible, infrared, and
  microwave sensor systems

• Visualization or Representation Written
  descriptions
• Charts
• Diagrams
• Tables
• Analysis
• Heart of geographic research
• Objective analysis is to discover patterns and
  establish relationships so that hypotheses can be
  established and models be built

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• Remote Sensing acquisition of data about earths
  surface from satellite images are transmitted in
  digital form.
• Example used with Hurricane Katrina to monitor
  areas of impact

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Using todays technology

• GIS
• a computer system that can capture, story, query,
  analyze, and display geographic data.
• Primary requirement for data to be used in GIS is
  that the location variables are known
• Any variable that can be located spatially can be
  fed into GIS
• Data capture- putting the information into the
  system
• Most time consuming
• Farmed out to cheap labor countries

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Layers of a GIS
A geographic information system (GIS) stores
information about a location in several layers.
Each layer represents a different category of
information.
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Geographical Information Systems

• GIS technology can render visible many aspects of
  geography there were previously unseen
• Images that could never be drawn by hand
• GIS can put places under the microscope, creating
  detailed new insights using huge databases

• Military applications
• Allows infantry commanders to calculate line of
  sight from tans and defensive emplacements
• Allows cruise missiles to fly below enemy radar
• GIS allows an enormous range of problems to be
  addressed
• Geodemographic research
• Uses census and commercial data about the
  populations of small districts in creating
  profiles for market research

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• History of the Map
• 2300 B.C.E.
• Babylonians
• 800 B.C.E.
• Turkish map ocean currents
• 500 B.C.E.
• 1st geography book commissioned

• Important Names
• Aristotle- determined that the earth was
  spherical
• Eratosthenes- coined the word geography and
  determined the circumference of the world

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Maps

• Uses
• Describe data
• Sources of data
• Tools for analysis
• Representations of the world
• Usually two-dimensional graphic representations
  that use lines and symbols to convey information
  or ideas about spatial relationships

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Types of Maps

• Topographic Maps
• Designed to represent Earths surface and to show
  permanent features such as buildings, highways,
  field boundaries, and political boundaries
• Device for representing the form of Earths
  surface is the contour
• A line that connects points of equal distance
  above or below a zero data point, usually sea
  level

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Types of Maps

• Reference Maps
• Show common features such as boundaries, roads,
  and mountains
• Thematic Maps
• Designed to represent the spatial dimensions of
  particular conditions, processes, or events

• Isopleth maps
• Maps based on isolines
• A line that connects places of equal data value
• Dot maps
• Single dot or other symbol represents a specified
  number of occurrences of some particular
  phenomenon or event
• Choropleth map
• Tonal shadings are graduated to reflect
  variations in numbers, frequencies, or densities

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Thematic Maps

• Isoline line represents constant quantity (ex
  elevation)
• Proportional Symbol size of symbol rep relative
  magnitude of value
• Dot Map dots show specific location of
  occurrences
• Coropleth uses color to rep data
• Cartogram transform country size relative to data

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CARTOGRAM - POPULATION
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COROPLETH MAP
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• Map Scale
• refers to the relationship of a features size on
  a map to its actual size on earth
• Ratio between linear distance on a map and linear
  distance on Earths surface
• Usually expressed in terms of corresponding
  lengths
• as in one centimeter equals one kilometer
• or as a representative fraction
• Small scale maps bigger fraction
• Large scale maps smaller fraction

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Scale Differences Maps of Florida
The effects of scale in maps of Florida. (Scales
from 110 million to 110,000)
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Types of Scale

• a. Fractional
• - shows the numerical ratio between distances
  on the map on earths surface
• example 124,000
• Means 1 map unit
• 24, 000 units on ground

• b. Written
• -relationship between the map and earth
  distances in words
• example 1 inch equals 1 mile
• 1st number represents maps distance
• 2nd number represents earths distance

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• C. Graphic
• -consists of a bar line marked to show distance
  on the earths surface
• example
• what scale you use depends on what information
  you are portraying!

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Projection
talking map

• -the scientific method of transferring locations
  on the earths surface to a flat map
• -earths surface is curved and not a perfect
  sphere. It is impossible to represent on a flat
  plane without distortion

• -Four problems
• 1. the shape of an area can be distorted
• 2. the distance between two points may increase
  or decrease
• 3. the relative size of different areas may be
  altered so that one area may appear larger
• 4. the direction from one place to another can
  be distorted.

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the Solution?????

• Different types of projections!
• -Equidistant Projections
• -can represent distance accurately in only one
  direction (usually north-south)
• -usually provide accurate scale in perpendicular
  direction( equator)
• -most aesthetically pleasing

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Types of Projections

• Mercator preserves direction but distorts area
  (higher latitudes distorted - Greenland appears
  huge)
• Fuller maintains accurate size and shape
  completely rearranges direction
• Robinson distorts all 4 but minimizes errors in
  each (most balanced)
• Azimuthal puts N or S pole at center of mapview
  of looking up or down at earth

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Fuller Projection
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Projections

• Conformal
• Projection on which compass directions are
  rendered accurately
• Example a Mercator Projection
• Compass bearing is plotted as a straight line
• Used in navigation for hundreds of years
• Benefits
• Represents the shape of landforms, but not equal
  in area because sizes of landforms are
  drastically distorted
• direction is consistent
• map is rectangular
• Often used in classrooms

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World Time Zones
The worlds 24 standard time zones are often
depicted using the Mercator projection.
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Projections

• Azimuthal
• Designed such that compass directions are correct
  only from one central point
• Benefits
• Can be equidistant
• Direction is accurate
• Uses
• Show air-route distances from a specific location
• Or equal-area

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Projections

• Equal-Area or Equivalent projections (Gall-Peters
  Projection)
• Portray areas on Earths surface in their true
  proportions
• Examples
• Eckert IV
• Bartholomews Nordic
• Mollweide
• Used for thematic maps showing economic,
  demographic, and cultural data

• Aesthetic maps
• More important than conformality, equivilance, or
  equidistance
• Examples
• Times Projection
• Used in many world atlases
• Robinson Projection
• Used in National Geographic publications

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Robinson Projection -shows uninterrupted
projections -useful for displaying the oceans
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Projections

• Peters
• Deliberate attempt to give prominence to
  underdeveloped countries of equatorial regions
  and the Southern Hemisphere
• Adopted by United Nations
• Shape gives shock value

• Cartogram
• Usually small-scale thematic maps
• Space is transformed according to statistical
  factors
• Largest mapping units represent greatest
  statistical values