Get Started with GIS Mapping
Part 1of 2, January 2010
Agenda for this section
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
What is GIS
Wide spectrum of complexity
Combination of hardware, software &
Can be one single large system or a suite
of tools or one small tool depending on
Data is key, design and color makes it
more informative and appealing.
Terms that we will come across
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
Projection – transformation of a map from a spherical object
(Earth) to a flat sheet of paper.
Google Earth Navigation
Exploring Google Earth
Copy Image/ Print Scr
Tools – Options
Adding your own placemarks to a folder
and saving a KML file
Google Earth – some best practices
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
Point Maps versus Thematic Maps
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.
Example of a simple point map
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.
Data Preparation - Planning
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
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.
Example of a base map
map of New
Example of a base map
Exploring the Census website
TIGER/Line Shapefiles from
Note that these are shapefiles and need
conversion to kml/kmz to be used on GE. (AFF
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!
AFF Mapper – Basic
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.
AFF Mapper - 1
Can be used for 2
◦ To convert
shapefiles to KML
for viewing on GE
◦ To combine
converting to KML
for viewing on GE.
AFF Mapper - 2
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.
The Census KMZ Mapper
The Census KMZ Mapper
Downloaded KML visualized in Google
Percent Population Without Access to Private Auto in Whole State
Data Preparation - Geocoding
Can geocode at different address levels
like state, county, zipcode, complete
Multiple ways, differences in accuracy,
daily limits, one time activity
Using KMLGeocoder on desktop
Zip data with lat/long for each state
Mapping your case data - points
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.
1. Assemble a set of tools for mapping
2. Begin a library of base files and data files for
mapping on your computer/server
3. Find sources of data for your region – many
local governmental entities and health related
organizations are good sources.
4. Think about what sort of maps and
visualizations work best for each purpose
5. Discuss maps and mapping practices with
Resources and Interesting Mapping
Applications - 1
Google Earth User Guide
Rural Assistance Center Maps
Resources and Interesting Mapping
Applications - 2
Download applications here
◦ Statewise Geocoded Zip codes
◦ Regional Legal Aid boundary files
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 email@example.com)
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.
LSNTAP GIS Resources
More roundtables and trainings and Q&A
sessions in the new year.
GIS mailing list being resurrected – do sign up
and participate https://lists.mayfirst.org/cgi-
GIS Resources section on LSNTAP.org updated
Set up a meeting with Madhu if you need
support. Email firstname.lastname@example.org
Send links to any interesting mapping resources
or data resources you find to