Transcript Map, Photo and Satellite Image Interpretation

Map, Photo and Satellite
Image Interpretation
Unit 3
Earth Science: Mapping the Earth
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Video: 20 minutes
https://www.youtube.com/watch?v=SXB1Z_CxBK0
History of Maps
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Early maps
• Sketches
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Later maps
• Better drawings
• Misinformation
• Artistic portrayal / vision (imaginative)
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Modern maps
• Accurate
• Scientific
Pietro Vesconte's World Maps, 1321,
from Marino Sanudo's Liber secretorum fidelium crusis
(oriented with East at the top)
http://www.henry-davis.com/MAPS/LMwebpages/228A.html
Nova Et Aucta Orbis Terrae Descriptio Ad Usum
Navigantium emendate . . .,
Gerard Mercator's famous world map, 1569
http://www.henry-davis.com/MAPS/Ren/Ren1/406.htm
Map of the Danish Kingdom, 1629, by Janssonius.
http://academic.emporia.edu/aberjame/map/h_map/h_map.htm
Today’s Maps
GIS - TODAY
https://www.youtube.com/watch?v=6AlH5TvFoLw
Today: GIS
http://ssnds.uwo.ca/sscnetworkupdate/2006winter/gissupport.html
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Cartographer
Relative location
Terms
• Orientation of a place, ie. North of Fredericton
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Scale:
• The relationship between distance on the map and the
corresponding distance on the ground
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Large scale map
• Shows a small land area in great detail
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Small scale map
• Shows a large land area with less detail
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Spatial data:
• the information to create a map
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Data collected for a map can be:
• Qualitative data - buildings, roads, rivers
• Quantitative data – elevations, air temperatures,
population density
Maps are:
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Fundamental tool of a geographer
• Way of recording and storing information
• Means of analyzing locational distributions and spatial
patterns
• Methods of presenting information and communicating
findings
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Essential
• Visually convey large amounts of spatial information in
an easy to read format
• Easier to see patterns and distributions
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Map making is not a static field
• Evolving with technology
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GIS – Geographical Information Systems
GPS – Global Positioning System
Tools Used by Geographers
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GIS
GPS
Maps
Magnetic Compass
Altimeter
• A device used for measuring elevation of an object above a fixed level
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Planimeter
• A device used to measure distances
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Radar
• A means of detecting objects using radiowaves that reflect off of them.
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Sonar
• A means of detecting objects underwater using sound waves
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Used to map the ocean floor
Sextant
• A measuring tool used to measure angle of elevation of a celestial object with
respect to the horizon
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Chronometer
• Timekeeper / Determines longitude by celestial navigation
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Rulers
String
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List all the map types you know of or
have used.
• How essential were they to you
completing your goals?
Different Types of Maps
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Road map
Political map
Economic or resource map
• Geological map
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Shaded relief map
• Map showing relative elevations / height of land (uses
color or shading)
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Topographic map (contour)
• Shows the elevation of land at all points
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Thematic maps
• Soil distribution map
• Climate mat
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Provincial map
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Maps of the Nepisiquit River
• Various maps to display the same area
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Which one do you like? Why?
• Contour, color, 3D
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Key: The more technology we have
incorporating information, the more
skill that is required
Parts of a Map
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Elements found on virtually all maps
• 1) Scale (distance)
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Should always be indicated or implied
Verbal, numeric or graphic form
On some maps, scale varies across the area
• 2) Orientation (direction)
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True North – direction to the North Pole
Magnetic North – moves due to changing geophysical condition
of the earth’s crust and core
Many maps have both
Key: Most maps made today are oriented towards the True
North even though compass readings are angled to the
Magnetic North
• 3) Legend
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Lists the symbols and what they mean
These must be precise
Key: Not all maps require legends – sometimes important
information is captioned or placed directly on the map
The important thing here is to remember
that a compass points not to true north
(e.g. the north pole, the geographical
northernmost point of the Earth) but to
magnetic north (the magnetic north end of
the Earth's 'bar magnet'). These two are
not in the same position (indeed the
position of magnetic north varies with
time). The apparent position of magnetic
north will vary according to your location in
the world (most importantly your latitude)
Magnetic north varies with place and time.
“The National Geomagnetic Program of Geological
Survey of Canada monitors the movement of the
north magnetic pole and most recently determined its
precise location in a 2001 survey. They've determined
that the pole is moving at approximately 25 miles (40
kilometers) each year.
The north magnetic pole moves on a daily basis, too.
Every day, there's an elliptical movement of the
magnetic pole about 50 miles (80 kilometers) from
its average center point.”
http://geography.about.com/od/learnabouttheearth/a/northpole_2.htm
Parts of a Map
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Elements essential for context
• 4) Title
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Wording, letter size, placement
• 5) Projection
• 6) Cartographer
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Who made the map
• 7) Date of production
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When it was made / this gives validity in
some cases (think accuracy)
Parts of a Map
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Elements used selectively to increase map
effectiveness:
• 8) Neatlines
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Border / frame
• 9) Locator maps
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Maps that are used to place the larger map
in context
• Map of New Brunswick may have a large
Canadian map
• 10) Inset Maps
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Close up of an area of the map
Activity 1
Choose a map.
 Complete Activity 1 by filling in the
blanks with related information.
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• Did you find all of the expected
elements?
• If not, which information was missing?
• Why is this information missing?
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Choose a second map (different) and
repeat.
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Look at the list of features you
originally identified in your maps?
What is different about this list and
Activity 1 features?