4/13/2015
Developments in cartography in the 20th and 21st centuries
-> digital mapping ~1980s to present
1900s National Atlases: The first edition of the Atlas of Canada
was in 1906, the world's second national atlas (after Finland, 1899)
 also online 1994, solely online 1998 -> http://atlas.gc.ca/
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Review: Map projections – 3 major groups
(based on projection surface)
Conic
Cylindrical
Azimuthal (Planar)
Sub-groups based on projection orientation: normal, transverse, oblique
Possible Properties (mutually exclusive) : area, shape, distance
4. Pseudo-cylindrical Projections - 19th/20th century
These are geometrically constructed.
The parallels are generally equally spaced but are more
proportional to their real length to reduce distortion.
Cylindrical
Mollweide 1857
http://www.progonos.com/furuti/MapProj/Normal/ProjPCyl/projPCyl.html
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Pseudo-cylindrical projections
e.g. Mollweide
-show the whole world with least overall distortion (and are equal-area)
Tissot’s Indicatrix: ‘circles are equal-area … but not shape
Mercator’s projection: preserves shape, but not area ->
Sinusoidal ~ 1570
- parallels are exactly the right length
But shape distortion is high
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Robinson projection – adopted by National Geographic in 1988
Poles drawn as lines to create better shapes
(Arthur Robinson)
http://www.mapsofworld.com/projection-maps/robinson/world-political-light.html
Winkel Tripel projection – adopted by National Geographic in 1998
Oswald Winkel
Not conformal or equal-area or equidistant but a good ‘triple’ compromise
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Interrupted projections (Goode’s homolosinal)
John Paul Goode
Oblique Mollweide
(obliques are used sparingly)
http://idlastro.gsfc.nasa.gov/idl_html_help/Pseudocylindrical_Projections.html
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Excellent use
of oblique
Mollweide
1945
Photogrammetry
> world war 1
World War II
Air photography
enabled faster
topographic survey
especially for remote
areas like Canada
Vancouver (Stanley Park,
downtown, west
vancouver, UBC) ->
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Photomosaic 1960 (pre-NASA): Orthographic projection
Like Earth, longitude
zero is arbitrary – a
feature is chosen
The Prime Meridian
of the Moon lies
directly in the
middle of the face of
the moon visible
from Earth.
Prince George: early post-war changes viewed on air photos
1944
1957
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The Universal Transverse Mercator (UTM) System
Adopted by Canada in 1947 for topographic mapping
oEach UTM zone is 6 degrees of longitude wide, each with a Central Meridian
o The UTM system consists of 60 TM projections (UTM is a system of projections)
o Polar areas use the azimuthal stereographic projection
Cylindrical
Projections
e.g. Mercator
Normal view
Mercator
(16th
century)
Transverse Mercator
http://www.progonos.com/furuti/MapProj/Normal/ProjCyl/ProjCEA/projCEA.html
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The TM projection is
the basis for the
(Universal) UTM
system used in
many countries
1 zones
6 degrees
3 maps
UTM zones (5): BC ->
Canada has 16 (7-22)
Canada Albers Equal Area Conic:
Central Meridian: -96 Latitude Of Origin: 40
First Standard Parallel: 50 Second Standard Parallel: 70
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Project: Remember to ‘project’ from Geographic to UTM
Hillshade from Geographic projection … 2 blocky grays – pixel size = e.g. .00017 (degrees)
Its doesn’t work at all if you set pixel size to 50 (= 50 degrees – how big is that?)
Hillshade from UTM data – full range of grayscales (256)
Projections are very tricky!
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Dougherty Creek Campsite Design / Development Project
Tabor Mountain Recreation Society (TMRS)
Contacts
Phil Mullins (Outdoor Rec & Tourism, UNBC): [email protected]
Ken Hodges (Tabor Mountain Rec Society): [email protected]
Possible summer ‘internship’ - mapping skills useful
Also ongoing mapping needs for TMRS
Please contact RW or Phil Mullins
http://www.progonos.com/furuti/MapProj/Normal/ProjAppl/projAppl.html
Present and fossil teeth suggest several migration waves in the past, when reduced
sea levels created bridges between now isolated Japanese and Aleutian islands.
Cassini = Transverse plate carree
(equirectangular)
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Example of misuse of Mercator projection: (area distortion)
Global transparency / lack of corruption
[Area of Australia: 7.7 million km2 Ellesmere Island: 200,000 km2 Alaska: 1.5 million km2]
Conformal projection Mercator
Equal-Area projection
Gall – Peters 1855/1973
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http://www.xkcd.com/977/
Projections – examples and uses
http://www.progonos.com/furuti/MapProj/Normal/TOC/cartTOC.html
ArcGIS supported projections:
http://resources.arcgis.com/en/help/main/10.1/index.html#//003r00000017000000
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Summary – use of projections
Equal-area: thematic distributions (area)
Conformal:
navigation (shape)
Equidistant: measuring distances from a point/line
Azimuthal:
polar areas
Cylindrical:
equatorial areas
Conic:
mid-latitudes
Pseudo-cylindrical : whole globe / thematic
Special purpose: oblique
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Digital mapping 1980s ->
Increased access to data, hardware, software ……. and travel
Digital mapping
1960s: First digital maps (experimental)
1970s: First software but expensive hardware
1980s: GIS software and PCs (still expensive)
1990s: Hardware/software affordable – but few data
2000s: Data becomes liberated; >>more after 2005
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Advantages of digital over manual mapping:
 Less artistic skills needed
 Colours, patterns easy to apply
 Easy to make changes and updates
 Conversion of map projections
 Integration of geomatics –mapping, GPS, imagery
 .. and computers being ‘cool’ (if they don’t freeze)
Disadvantages of digital over manual
 So much new to learn ..
 More stressful ?
 GRRRR … computers … software
 Why is it so slow ?
 What is it doing now ?
 Why do computers hate me ?
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Digital plotting – ‘small runs’ – ink-jet plotters - $10 / sq.foot
Large runs – offset printing (+set-up charge) - $000s
Digital plotting – Laser or ink-jet printers
$1 per page (e.g. Barry )
Or just don’t print it –
no hardcopy needed
leave it onscreen
(‘softcopy’)
- No print cost
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2005: Map viewers: e.g. Google Maps/Earth/PGmap)
Mars Global Surveyor: Mars Orbiter Laser altimeter
Unprecedented access to map data and onscreen mapping
All online mapping – Google, Bing, OpenStreetMap use the web
mercator
Web Mercator shares some of the same properties of the standard Mercator
projection: north is up everywhere, rhumb lines are straight, but areas near the
poles are greatly exaggerated.
Shape-preserving = zoom in/out are quick as shape does not have to recompute
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Google Moon: http://www.google.com/moon
Web Mercator ET !
Mars
Globalmapping:
Surveyor:e.g.
Mars
Orbiter
Laser
altimeter
Planetary
Google
Mars
(+Street
View)
MARS:
DEM resolution in the z = 30cm from LiDAR
http://www.google.com/mars/
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