C-squares concept: Data items are represented by the grid squares in which they are located

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C-squares conceptData items are represented by
the grid squares in which they are located
1 Data items
2 Data items and relevant grid squares
3 Grid squares alone
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Principal purpose of c-squares is for spatial
indexing and spatial queries - secondary
application is for mapping - another is for data
aggregation, e.g. for analysis, reporting,
exchange - can also be efficient e.g. in OBIS
case, map lt2,000 squares rather than 50,000 data
points for one species (over 95 faster) - or,
map 70,000 squares rather than 9 million points
(all the data...)
OBIS data all vertebrates (3.4 million
records) ...
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• First c-squares mapper constructed at CMAR,
  Hobart in early 2002 used by CMAR applications,
  OBIS, FishBase and Cephbase
• Mapper upgraded (v2) in 2003 to map multiple
  sets of squares concurrently, and support click
  on map functionality (e.g. to do a get the
  data query)
• Minor upgrades in 2004/5 to suit needs of
  AquaMaps project, also ported to faster machine
  at CMAR, Hobart (20x speed increase...)
• Mapper installation replicated at IfM-GEOMAR
  (Germany), and Swedish Museum of Natural History,
  in 2005/6, for FishBase/AquaMaps and INCOFISH
  project use

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• Jan-May 2006 Mapper upgraded (v3) to use more
  detailed graphics (supporting seamless pan and
  zoom across the entire world), better seabed
  detail, more realistic land images
• New globe views introduced (with new graphical
  user interface to spin the globe around), based
  on Hari Nairs Xplanet software
• Squares can be enhanced for extra visibility
  (bold or intermediate), or plotted at fine
  scale as desired
• Land masking is available on globe views and
  all derived maps
• Gridlines have been added to maps based on
  globe views to help user orientation
• Maps based on globe views have more correct
  representation of proportion when zoomed in, also
  supports polar views (ideal for plotting Arctic,
  Antarctic data)
• Quite a bit of background optimization to
  minimise redraw wait times, etc. once globe views
  have been created.

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New world base maps...
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Improved land and seabed resolution for all
areas...
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Improved land and seabed resolution for all
areas...
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Improved land and seabed resolution for all
areas...
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Globe views available from all world maps
continuously tiltable and rotateable
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Ability to view polar regions with / without
ice cover, as preferred
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Ability to view polar regions with / without
ice cover, as preferred
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Ability to view polar regions with / without
ice cover, as preferred
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Land mask available for all new maps
Land mask off (all current OBIS fish data)
Land mask on
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Three ways to try out the new features

• Via any OBIS species page, or group clickable
  map
• Direct call to mapper with a suitable c-square
  code or codes, e.g. http//www.obis.org.au/cgi-bin
  /cs_map.pl?csq1000
• Via mapper entry page on obis.org.au (follow
  link tools)

credits Mapper development Tony Rees, Miroslaw
Ryba, Philip Bohm (CMAR) Xplanet (globe
rendering) Hari Nair, JPL (via SourceForge)