geographic information systems and science: enabling a location-based technology michael f....

Geographic Information Systems and Science: Enabling a Location-Based Technology

Geographic Information Systems and Science: Enabling a Location-Based Technology

Michael F. Goodchild

University of California

Santa Barbara

Geographic informationGeographic information

Information that links properties to positions on or near the Earth's surface– the information of maps– but much more besides

The atomic form– <x,z>– point observations, e.g. at weather stations– observations about lines, areas

Three technologiesThree technologies

Earth measurement– the accurate determination of position on

the Earth's surface

/dR

Eratosthenes, 200 BC

Perfect sphere, radius 6378 km

Ellipsoid of rotation, flattening 1/300

Ellipsoid Semi-major axis 1/flatteningAiry 1830 6377563.396 299.3249646Modified Airy 6377340.189 299.3249646Australian National 6378160 298.25Bessel 1841 (Namibia) 6377483.865 299.1528128Bessel 1841 6377397.155 299.1528128Clarke 1866 6378206.4 294.9786982Clarke 1880 6378249.145 293.465Everest (India 1830) 6377276.345 300.8017Everest (Sabah and Sarawak) 6377298.556 300.8017Everest (India 1956) 6377301.243 300.8017Everest (Malaysia 1969) 6377295.664 300.8017Everest (Malaysia, Singapore) 6377304.063 300.8017Everest (Pakistan) 6377309.613 300.8017Modified Fischer 1960 6378155 298.3Helmert 1906 6378200 298.3Hough 1960 6378270 297Indonesian 1974 6378160 298.247International 1924 6378388 297Krassovsky 1940 6378245 298.3GRS 80 6378137 298.257222101South American 1969 6378160 298.25WGS 72 6378135 298.26WGS 84 6378137 298.257223563

Clarke Ellipsoid of 1866

a = 6378206 m

1/f = 294.98

World Geodetic System of 1984

a = 6378137 m

1/f = 298.26

The Global Positioning SystemThe Global Positioning System

Three technologiesThree technologies

Remote sensing– satellite-based– aircraft, drones

• Roofs versus roads

• Road types

• Major/minor roads

• Vegetation cover

• Shadows

• Construction areas

Three technologiesThree technologies

Geographic information systems– digital representation of geographic data– editing, transformation, analysis, modeling,

visualization, decision support– virtually any conceivable task

The Canada Geographic Information System– 1966

The geographic information industriesThe geographic information industries

GPS industry– $1 billion– European Galileo

Data supply industry– remote sensing

• NASA $10 billion• other US civilian agencies $10 billion• military and intelligence $30 billion• 500,000,000,000,000 sq m• petabytes of information online (1PB=1015 bytes)

The geographic information industriesThe geographic information industries

GIS software– desktop, Web, enterprise– $1 billion– ESRI 30%– Intergraph 20%

Location-based services– Web– cellphones

Location-based servicesLocation-based services

Information services– provided by systems that know where they

are– and modify information accordingly

How does a system know where it is?How does a system know where it is?

GPS onboard– cellphone

Triangulation from towers Determined at system build time IP address

What kinds of information?What kinds of information?

Nearby services Visualization of invisible features

– underground– around the corner– in the past– visually impaired user

Location-based gamesLocation-based games

Played on location-enabled devices– cellphones

New directionsNew directions

Social sciences– most early applications were environmental– health, business, social services

Dynamics– from how the world looks to how the world works

SimulationsSimulations

1.8 vehicles per driveway Driver behavior influenced by:

– lane width– slope– view distances– traffic control mechanisms– information feedback– driver aggressiveness

770 homes– clearing times > 30 minutes

2D clip

3D clip

Policy implicationsPolicy implications

Addition of new outlets Better deployment of traffic control

resources Understanding the risk Reduce cars used per household Problems of shut-ins, elderly, latch-key

kids

Putting it all togetherPutting it all together

www.earthviewer.com

ConclusionConclusion

A rapidly growing industry– tightly connected sectors

Applications across the spectrum of human activities– commerce– research– everyday life

Growing familiarity– GIS a widely recognized acronym– in-car navigation, LBS, Web mapping

Exciting new directions