Digital Mapping Workshop Part 1

From text to map

Behind any beautiful digital map lies the reality that every point, line or polygon is generated by some form of numerical and textual data.  Here is an example of a “placemark” written in KML:

	<name>Visualization Portal</name>
	<description>Don't fall asleep! Data is fun!</description>
		<coordinates>-118.44339036032716, 34.069750838829485</coordinates>

A few more options…

	<name>Visualization Portal</name>
	<description>Don't fall asleep! Data is fun!</description>
		<coordinates>-118.44339036032716, 34.069750838829485</coordinates>

History mapped

A paper map can be scanned and made digital.  As an image, it does not know “where it is”, in terms of its spatiality.  A process called “georeferencing” allows us to “spatialize” printed documents, and put them in the context of other spatial layers.  Here is an example of one of the most famous historical maps, the “John Snow Map” from 1854 that illustrates a Cholera outbreak that attacked London.

John Snow Cholera map (1854)

The same map can be visualized on a GIS platform, in this case, Google Earth:

John Snow map on google earth

[John Snow in Google Earth]

[TBS_ALERT color=”success” heading=”How to view in Google Earth”]

  1. Right click on the hyperlink and select “copy link address”
  2. Open Google Earth, Add, Network Link
  3. Give the network link a name, and paste the hyperlink


Los Angeles 1857-2002

LA 1881

[Historical Los Angeles Maps in Google Earth]

The power of spatial imagery

Google Street View

Screen Shot 2015-04-08 at 4.10.27 PM

Screen Shot 2015-04-08 at 4.11.25 PM

Screen Shot 2015-04-08 at 4.11.58 PM



Ukedo Street View

Hurricane Katrina

New Orleans 4-17-2005

New Orleans 8-30-2005

[Hurricane Katrina in Google Earth]

Source: National Geospatial-Intelligence Agency,

Banda Aceh, Indonesia

aceh 6-22-2004

aceh 1-27-2005

aceh 2-22-2009

Sendai, Japan

sendai 12-9-2009

sendai 3-13-2011

[Japan Disasters Google Earth KMZ]

Census Data

census data on google earth