Portraying the Earth GPS, RS, and GIS as geographic tools Lab 3

Concepts Types of maps Categories of data on maps Location data Attribute data 3 representations of data Global Positioning Systems Remote Sensing Geographic Information Systems

Types of Maps “map”: representation of spatial distribution of selected phenomena Maps show what is where  General Purpose/Reference maps  Display natural & man-made elements on the earth  Ex: Landscape features, Political boundaries, etc.  Special Purpose/Thematic/Statistical maps  Illustrates characteristics of a geographical area  Ex: Population, Unemployment, Ethnicity, etc.

Data on Maps Categories of Data Location Data: coordinates, addresses “Where is it located?”

Data on Maps Categories of Data Attribute Data: descriptive & informative “What kind of item is there?” and “How many items are there?”

Data on Maps Where does it come from? Scanned maps Field sampling Aerial photographs Satellite images Databases (location & attribute information)

Data on Maps Three representations POINTS single physical item Building, person, tree LINES “arcs” Street, river, contours AREAS “polygons” Lakes, political units “Layers” of data

Global Positioning System (GPS) Satellite-based navigation system, allows users to find their latitude/longitude location. 24 satellites in orbit (U.S. Dept of Defense). Originally for military application, but made available for civilian use in 1980s. Each satellite circles the Earth twice a day. GPS works in any weather condition, anywhere in the world, 24 hours a day.

Global Positioning System (GPS) Three elements Space Satellites in orbit Control Ground stations around the world that upload data to the satellites and control their orbits User Receiving end of the satellite transmission information

Global Positioning Systems (GPS) How do they work? Use triangulation to provide user with location  A GPS receiver must be locked on to the signal of at least 3 satellites to calculate latitude and longitude.  With four or more satellites, the receiver can determine the user's 3D position (latitude, longitude and altitude). You holding a GPS receiver

Remote Sensing Collecting information about the Earth without direct contact 2 examples Satellite Imagery Aerial Photographs

Remote Sensing Satellite Imagery Right: Pearl Harbor, Hawai’i Far Right: Italy and Greece Below: Light pollution at night

Remote Sensing Aerial Photography Below Left: Houston, TX Below Center: Chicago, IL Below Right: Turner Field

Geographic Information Systems (GIS) A system of software, hardware, data, and user which allows us to visualize, manipulate, analyze, and display spatial data Maps are a product of GIS – a way to spatially visualize the data Often called “smart maps” because they link databases to a map, with interactive capabilities GIS is a problem-solver Ask a question Combine various forms of data in a program Interactive capabilities allow for analysis and final map

Geographic Information Systems (GIS) Think of it this way… Data in a database: not easy to interpret

Geographic Information Systems (GIS) But… Data represented and analyzed in a spatial manner: easier interpretation

Geographic Information Systems (GIS) Example: Atlanta Area Schools

Geographic Information Systems (GIS) Helpful not just to Geographers Emergency Services Fire, police, 911 Environmental Agencies Monitoring environmental quality standards, flooding Business Marketing, store location analysis, customer data Industry Transportation, communications, pipelines Government Census Bureau statistics, historical preservation Education

Geographic Information Systems (GIS) GIS on the Internet What is and what isn’t GIS? Think carefully and observe the tools you have available on each website. Google Maps National Geographic Map Machine GEOMAC Wildland Fire Support City of Clearwater, Florida The European Pollutant Emission Register Downtown Los Angeles Homeless Tracker