Geographical Information SystemsGI Science (NB rebrand taking
hold: Spatial Data Science) Conceptualising reality in a computer
model Not just maps or manipulation Why is GI important? Everything
happens somewhere Ability to attach multitude of information
Relationship between phenomena spatial co-incidence relate/transfer
info (attributes) between layers where co-incide
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Data acquisition/integration Data management/database
management electronic filing cabinet Data analysis Decision making
Visualisation/cartography
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Discrete entities with specific location Multiple attributes
for each feature PointPolylinePolygon Longley et al., 2005:
77.
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Continuous surface with changing values Elevation and
derivatives Satellite imagery Photographs Scanned maps Attributes
Each cell has single value This can relate to Value Attributes
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Mapping find spots across a site Points Multiple attributes can
be recorded Type of find Measurements Dating/period Material Record
number And of course implicitly spatial reference/location Permits
spatial analysis, incl. of all the attributes above Point-Pattern
Analysis Possible (e.g. Clustering?)
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Display density of IA sites found in the Lothians Grid (of
usually square cells) Each grid cell can show value relating to
density of sites per unit square Aggregate (zonal) measures of one
variable per grid
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Vector Historic Land Use Polygons Stops on the Grand Tour
Points: Attributes mood, time spent at each place, no. of mentions
in text whole new field of geol text analysis Raster Scanned maps
e.g. efforts of NLS in Edinburgh Historic e.g. wildlife surveys
grid squares, tetrads Any continuous surface to represent aggregate
stats
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In the field - data capture and recording; primary data Vector
Fieldwalking Find spots Monument location Trench locations Contour
surveys Full Plans In the lab (automated) digitising; geol text
analysis www.english-heritage.org.uk
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Maps Modern Can be vector or raster OS (OpenData, MasterMap)
Enviro, e.g. CEH, BGS Historical Old OS BGS? Other Historic
Maps/Plans Topography Geophysical imagery Remote sensing
Optical/RADAR/LiDAR Caracol LiDAR (www.britannica.com)
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Historical GIS Portsmouth/ex Edinburgh HGIS/US Rail Economics
Richard Healey (set up Edin MSc GIS) Online Resources Humphrey
Southall Great Britain Historical GIS A Vision Of Britain Through
Time Old Maps Online PastPlace: Rethinking gazetteers for the
semantic web (I.e. OLD meets NEW) Spatial Humanities Lancaster Ian
Gregory, ex MSc Texts, GIS, Places Project Census Analysis
Liverpool, Manchester, Edinburgh Urban Change, Health, Travel
Patterns, Deprivation Mostly recent data however some moves to more
historic analysis
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Visualising Urban Geographies Richard Rodger (History, Ed)/NLS
Chris Fleet Historical Transport Data/Network Evolution Lots of
attempts to recreate historic roads and railways (canals too?) but
many are static PDF! We need actual vector data to do any useful
analysis My destiny? One day! 3D Visualisation of Past Environments
(Again one day soon?)
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Primary Data mostly obtained by digitising of old records
either maps or tables, some collected (e.g. census records)
Secondary Data either pre-digitised and/or alternative accounts for
tabular data, or e.g. historic land parcels/parishes The past can
be tricky! Often historical data displayed on contemporary maps! A
pitfall?
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Data and Cultural Resource management Sites and Monuments
Records Historic Environment Records More flexible storage and
querying Topology preserved Go beyond one point in the landscape
Sophisticated querying/spatial testing Attaching detailed attribute
data to spatial objects Analysis of arch/histl sites within broader
context
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Public dissemination Search databases online
APIs/Screenscraping can be used to extract large data volumes
Heritage/Archaeological http://canmore.rcahms.gov.uk/ RCAHMS
(merging Historic Scotland) http://canmore.rcahms.gov.uk/
http://www.keystothepast.info/Pages/Home.aspx Keys to the Past
http://www.keystothepast.info/Pages/Home.aspx
http://archaeologydataservice.ac.uk/archsearch/ Arch. Data Service
http://archaeologydataservice.ac.uk/archsearch/ Historical GIS
http://maps.nls.uk/index.html National Map Library of Scotland
http://maps.nls.uk/index.html http://geo.nls.uk/urbhist/
Visualising Urban Geographies http://geo.nls.uk/urbhist/
http://www.visionofbritain.org.uk/ Vision Of Britain Through Time
http://www.visionofbritain.org.uk/ http://www.oldmapsonline.org/
Old Maps Online http://www.oldmapsonline.org/ NB: Lack of
standardisation. Not all may qualify as DBMS!
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Wiltshire County Council Sites and Monuments Mapping
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Google Maps (and Google Earth) Basic Functionality Online Full
Power via JavaScript powered web pages Over-reliance on commercial
megabusiness? OpenLayers Free and Open alternative (NB Open Free)
Other web map tools: E.g. MapServer, GeoServer
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Market leader in GIS software One of several ESRI ArcGIS
packages ArcScene, ArcCatalog Can handle most data types At a basic
level, is helpful for cartography and visualisation Many forms of
analysis available Multi-criteria analysis (prediction modelling)
Visibility Cost surfaces Networks However Closed, proprietary
software Not the only program available, and expensive (tho some
free components) Alternatives: MapInfo, GeoMedia, FME, CadCorp Open
Source GIS Much open source software available; modifiable,
extensible, fixable! GRASS, Quantum GIS, gvSIG many make use of
GDAL/OGR libraries http://opensourcegis.org/
http://opensourcegis.org/ Or e.g. R or Python stats, programming
both oft used for maps
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http://www.shc.ed.ac.uk/projects/longwalls/Method
ology/Visualisation.htm Byk Bedesten Casal de Freiria Rua and
Altivo, 2011: 3302 USGS (Sept 2011) LiDAR particularly good for
trees (top and bot = first and last)
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Previous examples may require GIS data/model be fed to 3D
modelling software for detailed work (or that model be constructed
in dedicated CAD/3D software) We can however very quickly create
effective visualisations of 2.5D landscapes in e.g. ArcScene (and
we can import 3D models from CAD/3D software) We can also very
quickly render animated visualisations of landscapes in GIS
software One example! (NB may not be made with Arc!):
http://www.satimagingcorp.com/gallery/quicktime-north- korea.html
http://www.satimagingcorp.com/gallery/quicktime-north-
korea.html
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We must be cautious when using computers Demonstrate how such
reconstructions are developed, and provide information indicating
our depth/lack of knowledge Full publication (data, methods,
limitations) Knowledge representation-what we think we know Dont be
blinded by their scientific aura Dont use them for the sake of it:
question them Technological determinism Dont tacitly accept their
results
Slide 27
What am I trying to get the GIS to do? How does this relate to
my aim? What data are available and will more need to be created?
What about data quality? Completeness? What is the state of
archaeological/historical knowledge? Therefore, how appropriate are
the data? What is the most appropriate scale at which to work? And
what scale/resolution are the data?
Slide 28
Data quality Different bodies hold data; different standards
Currency Completeness Representation of archaeological/historical
reality; and not 3D but 2.5D Technological determinism Packages can
only perform certain operations Algorithms themselves can be
restricting Phenomenological/experiential/ritual aspects not easily
mapped and analysed
