Part 1of 2, September 2010
Madhu Lakshmanan

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Brief introduction to GIS/mapping jargon
Exploring Google Earth (GE)
Point Maps versus thematic maps on GE
Base Maps and where to find them
The Census website
AFF Mapper – Part 1
The Census KMZ Mapper Application
Data Preparation – geocoding
Mapping point data
Resources/Homework

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Mapping
Wide spectrum of complexity
Combination of hardware, software & data
Can be one single large system or a suite of tools or one small tool depending on your requirement
Data is key, design and color makes it more informative and appealing.

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Layer – A slice of the geography of a particular area. On a paper map, one layer could be the roads, another could be parks, another could be places of interest.
Base Map – A layer that lends context to your data
Geocoding – Converting street addresses into spatial data that can be displayed on a map (usually a latitude and longitude pair)
Shapefiles – A data format that stores a particular geographic feature of a certain area. (it is usually a set of files) and is almost the de-facto standard. It is an ESRI-created format.
KML/KMZ – an XML based language schema for expressing geographic visualization. It is an official open standard for all geobrowsers.
Projection – transformation of a map from a spherical object
(Earth) to a flat sheet of paper.

Search
Panel
Google Earth
Toggle
Sidebar
Places
Panel
Transparency
Control
Layers
Panel
3D Viewer
Navigation
Controls

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Copy Image/ Print Scr
View Menu
Tools – Options
Navigation
Fly to
Layers
Adding your own placemarks to a folder and saving a KML file

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Play, Practice, Patience
Save as and keep your KML files organized in a separate folder on your drive.
Clear cache regularly after saving required data
Save without too many standard layers to keep kmz size down for emailing etc.
Use transparency slider
Actual screenshots are better than using the inbuilt GE copy tool – only copies the GE map and not any of your custom overlays
Look at KML in free time – very much like
XML.

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Point Maps usually give you information about a particular location on a map. They can be used for directions, descriptions and distance information among others.
Thematic Maps reflect a particular theme
(social, physical, political etc.) about a geographical area. It shows distributions in the form of shading or graphs rather than actual locations where people live.
Point and thematic maps can be layered atop one another to provide a wealth of information.

Location of major grocery stores in the Ann Arbor vicinity

Example of a simple thematic map from the
US Census
Percent Population below poverty by county in North Carolina.

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Having some idea of what you want to achieve with your map
What data do you have already?
What data do you need to acquire?
If you have to convert your data, what conversion tools do you need?
What maps can you reuse?
Data origin, metadata, processing
Discuss with other users, colleagues, peers

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Base maps or boundary maps help provide context to your data map. They do not contain any attribute information, they are just geography. They can be layered with the maps you create to give information that is not available or visible on the virtual globe (GE), such as county names/zipcodes etc.
If your mapping concentrates on a certain region (state/county etc), you need to create your base maps just once and save them, and these can be reused as many times as you need.

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Zip code boundary map of New
Mexico.

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County boundary map of
New
Mexico.

http://www.census.gov/

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Note that these are shapefiles and need conversion to kml/kmz to be used on GE. (AFF
Mapper)
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Advantage is that they are the ones that most datasets are based on, so compatibility is great
Download the shapefiles at the level you need, by drilling down to your state – county, MSA, zipcode etc. (Multiple files downloaded at the same time have an unzip problem, hence you need to do it one by one)
Make sure you name your unzip folder meaningfully since things will get confusing after downloading multiple maps!

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Created to make maps using census boundary files and American Fact Finder data
Rule-based, but simple to follow
Find a shapefile from http://www2.census.gov/cgi-bin/shapefiles/national-files
This is a one time task for a particular geography, so make sure to extract, rename and save the file safely.
Extract to a folder on your computer that you can find. There will be multiple files in the folder and they are all important.

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Can be used for 2 purposes
◦ To convert shapefiles to KML for viewing on GE
◦ To combine shapefiles with data and converting to KML for viewing on GE.

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Click on Input Shape – a browse window will open.
Navigate to the base map folder that you downloaded and unzipped earlier and point to the shp file in that folder.
Once that file is loaded, you will be able to see all the information in a tabular form – these are just geographical information and codes and identifiers.
Ignore the “Join Tables Settings” panel for this exercise.
In the Label Field column at the bottom, choose a field that will appear on the map, choose “Name” if there is such a field. Click
Render. You can change the color at this point, but remember that you can also do it in Google Earth depending on other layers you are using, so just say OK with the default color.
Click on Output KML and give it a name and location – very descriptive. I prefer to put it in the same folder as the shp file that was used to begin with.
Hit Go and wait for the “Finished” message. You will now have your KML file available to open in Google Earth.

http://ctasgis02.psur.utk.edu/tokml/Default.aspx

Downloaded KML visualized in Google
Earth
Percent Population Without Access to Private Auto in Whole State

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Can geocode at different address levels like state, county, zipcode, complete address, etc.
Multiple ways, differences in accuracy, daily limits, one time activity
Using BatchGeocoder.com
Using KMLGeocoder on desktop
Zip data with lat/long for each state

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Directly enter addresses into GE one by one.
(can import bulk if using Pro version)
Use a tool like KMLGeocode or batchgeocode.com to take your Excel address data and convert to KML directly – no identifying info needed other than address data and this can even be reduced to street level if you wanted to preserve some more anonymity.
Limit is 5000 a day.
GE shows a map with a scatter plot of your case data. A screenshot of this will not reveal any specific address information to a viewer but sharing kml will do that.

“Run” the geocoder and then Click on the “Download to KML file” button at the very bottom and you can have a saved file with the latitude and longitude information for your addresses.

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Assemble a set of tools for mapping
Begin a library of base files and data files for mapping on your computer/server
Find sources of data for your region – many local governmental entities and health related organizations are good sources.
Think about what sort of maps and visualizations work best for each purpose
Discuss maps and mapping practices with peers.

Resources and Interesting Mapping
Applications - 1
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NTAP GIS Resources http://lsntap.org/GIS_Resources_for_Google_Earth
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Census website http://census.gov
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American Factfinder http://factfinder.census.gov
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Google Earth User Guide http://earth.google.com/userguide/v5/
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Rural Assistance Center Maps http://raconline/org/maps
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Show@/USA http://show.mappingworlds.com/usa

Resources and Interesting Mapping
Applications - 2
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Download applications here http://lsntap.org/GIS_Resources_for_Google_Earth
◦ KMLGeocoder
◦ EarthPlot
◦ AFFMapper
◦ Shp2KML
◦ Statewise Geocoded Zip codes
◦ Regional Legal Aid boundary files

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Familiarize yourself with Google Earth and also with the
American Fact Finder part of the Census website
Go to http://www.justice.gov/eoir/sibpages/ICadr.htm
Pick any two states (try to pick atleast one with more than 1 entry!) and use Excel and batchgeocoder.com to plot those addresses on GE and save as a KML file.
Send me a screenshot of your GE file when you are done (to madhu@lsntap.org)
Download County level and 5 digit zipcode level base maps of your state from the TIGER site and try to convert them to KML using AFF Mapper.