SP.757 GIS Lab Exercise

Massachusetts Institute of Technology - Department of Urban Studies and Planning

SP.757 - Digital Imaging Seminar - In-Lab Notes, October 29, 2009

Geographic Information Systems (GIS) and Map Mashups

Joe Ferreira - http://mit.edu/11.520/www/labs/sp.757_labnotes_09oct29.html

Introduction

Examine digital imagery and mapping tools that allow geography and geospatial relationships to be visualized and analyzed
Borrow exercise from 11.188 (Urban Planning and Social Science Laboratory)
- an undergrad subject that satisfies the undergrad lab requirement
- Taught together with 11.520
- See class website: http://mit/edu/11.520/www
Do the first lab exercise from the class - Create a thematic map of Cambridge census data showing areas with high/medium/low income

Online mapping tools

Mapquest: http://www.mapquest.com
Google maps: http://maps.google.com
EPA's Enviromapper: http://www.epa.gov/enviro/html/em
MassGIS map viewer
- Main site: http://mass.gov/mgis/
- Data layers and download info: http://mass.gov/mgis/database.htm
- Map viewer: http://mass.gov/mgis/mapping.htm
Traffic, bird's eye, and other views:
- See '2D,' 'Traffic,' 'Bird's Eye,' etc tabs on Microsoft's Virtual Earth: http://www.bing.com/maps/
- Washington DC traffic (Maptuit/SmartRoute/Westwood-One site via Washington Post):
  - http://www.washingtonpost.com/wp-dyn/content/metro/traffic/
Geospatial OneStop (Portal for Federal GIS data)
- http://geodata.gov/
NCAR weather data
- Weather modeling example at the National Center for Atmospheric Research (NCAR):
- MM5 (mesoscale model, fifth-generation): http://www.rap.ucar.edu/weather/model/index.php?model=gfs
The (US) National Map
- http://nationalmap.gov/(cover page)
- http://nmviewogc.cr.usgs.gov/viewer.htm (direct link to mapping interface)
- USGS-led effort at coherent, cross-agency national map layers
Google Earth: http://earth.google.com

Introduction to GIS

ESRI's ArcGIS software
Lab exercises #1 from 11.520/11.188: http://mit.edu/11.520/www
Key ideas
- Vector ('connect the dots' boundary) model of objects in space
  - Links between objects on map and attributes in table
- Raster (digital photo as grid cells) model of space and its contents
  - orthophotos and coordinate systems
- Web services - MITOrtho button in ArcMap
Map mashups
- Mass election contributions - Google maps mashup in Boston Globe
  - http://boston.faneuilmedia2.com/gov/detail_map.html?from=top&zip=02116&z=13
- Other Google maps mashups: http://googlemapsmania.blogspot.com/#top
- Tagmaps (Yahoo maps + Flikr photos): http://tagmaps.research.yahoo.com
- Land ownership in Boston Neighborhoods - 'middleware' tools to control map mashup

Handling Orthophotos and High-Resolution Imagery in Photoshop

Photoshop focuses on image manipulation rather than processing based on coordinate systems and geographic proximity
However, Photoshop has some tools that facilitate the use and overlay of large, geographically referenced images
Lesson 13 of the Adobe CIB Photoshop CS3 book has illustrations and is available in the class locker:
- http://web.mit.edu/sp.757/www/Photoshop/CIBCS3-lesson13-infographics/

Exercise(Optional - just for fun!)

Start Google Earth:
- find your home town
- Explore navigation interface (zoom in/out, rotate and tilt, turn on/off buildings
Overlay WMS services on top of Google Earth
- Choose Add/.Image-Overly and use the following parameters:
  - Name: MassGIS-street-map
  - Link: paste this link (try it first in a browser window) http://maps.massgis.state.ma.us/mapaccess/main.jsp?dpi=120&request=GetMap&layers=MHD+Roads&styles=Class&srs=EPSG:4326&bbox=-71.1,42.35,-71.0,42.37&width=640&height=480&format=image/png&service=wms&transparent=true
  - Refresh-tab: set "when" to be "after camera stops"
- The MassGIS server will send an image overlay of local streets that Google Earth places in the appropriate place
Explore "GeoModeling" with Google Earth and Sketchup
- In Google Earth, zoom in to the MIT campus
- Place a to-scale model of Eiffel Tower on Briggs Field
  - Choose Add/Network-Link and select this file:
    - Z:\athena.mit.edu:\course\11\11.520\data\sketchup\eiffel_08nov06_v1.kmz
    - Which is also visible in an online AFS class locker (http://mit.edu/11.520/data/sketchup)
- Keep Google Earth open and start Google Sketchup as well
  - Open the saved Eiffel Tower sketchup file in:
    - Z:\athena.mit.edu:\course\11\11.520\data\sketchup\eiffel_mit_08nov.skp
  - Click the "view your model in Google Earth" button (3rd from right side of tool bar)
    - The sketchup model will be placed into Google Earth in the same location as determined by SketchUp from the registered image that came from a Google Earth snapshot.
    - Some machines in the MIT labs will not allow this method of moving 3D models from SketchUp to Google Earth (do to file writing permission issuses). In that case, from Sketchup, choose File/Export/3D-Model and save your model to disk in KMZ format (zipped keyhole markup language, KML). Then open the file in Google Earth via Add/Network-Link.
- Turn on 3D buildings in Google Earth and examine the scale of the Eiffel Tower compared with the playing fields and MIT buildings
- Explore additional Google Earth and Sketchup capabilities - e.g., you can drape photos onto wire frame building models so the photos provide a realistic facade for the buildings
- Think about how Eiffel Tower model might be encoded for efficient and standard hand-off to Google Earth
  - Introduction to KML: http://code.google.com/apis/kml/documentation/
- For more information about downloading and using Google Earth and Sketchup see:
  - Downloading Google Earth: http://earth.google.com/
  - Downloading Google Sketchup: http://www.google.com/sketchup/download/
  - Geomodeling with Google Earth: http://sketchup.google.com/support/bin/topic.py?topic=13681&hl=en
  - How to place a Sketchup model in Google Earth: http://sketchup.google.com/support/bin/answer.py?answer=36241&topic=13681
Do Lab #1 from 11.520/11.188: http://mit.edu/11.520/www/labs/lab1/lab1.html
- Cambridge map showing streets and location of 1989 housing sales
- Shade thematically based on median household income
- Open attribute table and test link between map and table

Created by Joseph Ferreira.
Last Modified: 28 October 2009 (jf)

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