P. A Selkin
Document1
Notes for CSIG 2010 Google Earth Session
Resource List:
Designing Educational Material for use in Google Earth
Peter A. Selkin, University of Washington Tacoma
paselkin@u.washington.edu
Background
Google Earth is a geobrowser available in several versions from Google
(http://earth.google.com/). Most of the information in this document relates to the
free, standalone version of Google Earth for computers (as opposed to mobile
phones). There is some discussion of the web browser plugin, which I refer to as the
“Google Earth Plugin.”
For those unfamiliar with Google Earth, several terms need definition:
A geobrowser is a piece of computer software designed to display geospatial data
interactively. Rather than focus on analysis or cartography – which GIS software
does well – geobrowsers typically prioritize ease of navigation, low price, speed, and
variety of pre-loaded imagery.
KML (http://code.google.com/apis/kml/documentation/kmlreference.html) is a
markup language similar in many ways to HTML. Just as web browsers read files
written in HTML, Google Earth (and most other geobrowsers) read KML files. Like
most any other document, KML files can be emailed, shared via the web, edited,
saved, loaded, etc. KML files come in two forms:
“Straight up” KML:
These are simply text
files written in the
KML language (e.g.
Fig. 1). These can be
manipulated and resaved in Google Earth,
or they can be edited
in a text editor.
KMZ files: These are
compressed KML files.
They can be
uncompressed using
most major
compression / archive
programs (e.g. WinZip,
Apple Archive Utility).
Uncompressing a KMZ
file always produces a
<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://www.opengis.net/kml/2.2"
xmlns:gx="http://www.google.com/kml/ext/2.2"
xmlns:kml="http://www.opengis.net/kml/2.2"
xmlns:atom="http://www.w3.org/2005/Atom">
<Document>
<name>KmlFile</name>
<Placemark>
<name>UWT Science Bldg</name>
<visibility>0</visibility>
<LookAt>
<longitude>-122.4384073668164</longitude>
<latitude>47.24529536589471</latitude>
<altitude>0</altitude>
<heading>-0.0006552918171444467</heading>
<tilt>0</tilt>
<range>286.151835542624</range>
<altitudeMode>relativeToGround</altitudeMode>
<gx:altitudeMode>relativeToSeaFloor</gx:altitudeMode>
</LookAt>
<Point>
<coordinates>
-122.4387785404096,47.24524136717367,0
</coordinates>
</Point>
</Placemark>
</Document>
</kml>
Fig. 1: Sample KML
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P. A Selkin
Document1
Notes for CSIG 2010 Google Earth Session
main KML file (called doc.kml by default). KMZ files are useful for distributing
materials that contain multiple parts, such as image overlays or icons.
The fundamental types of features in KML are placemarks and image overlays.
Placemarks contain vector data – points, lines, polygons, or even 3D models. Image
overlays are raster images that can be draped over topography (ground overlays),
free-standing at a specified location (photo overlays) or static in the Google Earth
window (screen overlays).
Introductions
Several good introductions to Google Earth and KML are available on the Web and in
print:
Wernecke, J. (2009) The KML Handbook. Upper Saddle River, NJ: Addison-Wesley.
339 pp. ISBN 0-321-52559-0. – The definitive guide to developing KML, by
Google’s Senior Technical Writer on the Earth team. Written as a tutorial, with
tons of exmples.
http://serc.carleton.edu/NAGTWorkshops/teaching_methods/google_earth/index.html
– Glenn Richard’s resource for teaching with Google Earth. Contains information
for users of a variety of levels. Geared particularly toward the geosciences. Has a
particularly handy tip sheet.
http://earth.google.com/tour.html – Basic tours of Google Earth features. Aimed at
novice users.
http://sitescontent.google.com/google-earth-for-educators/ - Google’s page on Earth
for Educators. Aimed at the novice to intermediate user.
http://earth.google.com/outreach/tutorials.html – Google Earth Outreach tutorials on
creating maps. Geared primarily toward nonprofits, but useful for educators as
well. Novice to intermediate technical level.
http://code.google.com/apis/kml/documentation/kmlreference.html – The complete
reference to KML and the Google extensions (non-standard features).
Intermediate to advanced technical level.
http://bbs.keyhole.com/ubb/ubbthreads.php/Cat/0 – Google Earth Community
Forums. This is where to ask for help.
Ready-Made Activities (and then some…)
http://serc.carleton.edu/sp/library/google_earth/activities.html – Activities
contributed to the Science Education Resource Center at Carleton College.
Primarily geoscience-focused.
http://www.lions.odu.edu/~ddepaor/Site/Google_Earth_Science.html – Declan de
Paor’s KML/KMZ files. These showcase a variety of geoscience demos in Google
Earth, particularly emergent models, where a block of the Earth can be “pulled
out” from the virtual globe.
http://www.juicygeography.co.uk/ – Noel Jenkins’ geography-related activities, many
of which use Google Earth.
http://stevekluge.com/projects/dlesege/dlesegemanual/manual.html – Steve Kluge’s
manual for designing Google Earth activities.
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P. A Selkin
Document1
Notes for CSIG 2010 Google Earth Session
Kluge, S. (2009) Encounter Earth: Interactive Geoscience Explorations. Upper Saddle
River, NJ: Addison-Wesley.
Design Notes and Tools
http://googleearthdesign.blogspot.com/ – Rich Treves’ blog on user interface issues
in KML and in geobrowsers often contains information useful to educators.
http://www.ldeo.columbia.edu/edu/DLESE/maptutorial/Title_page.html – Kim Kastens’
tutorial on research in cognition and maps.
http://kml-samples.googlecode.com/svn/trunk/interactive/index.html – Interactive
KML sampler. As close to WYSIWYG as Y can G when developing KML.
http://earth.google.com/outreach/tutorial_spreadsheet.html – Spreadsheet Mapper:
turn a spreadsheet of lat/lon data into a set of placemarks. Use for fewer than
400 points; otherwise use Fusion Mapper
(http://earth.google.com/outreach/tutorial_fusion_yourowndata.html).
http://www.gdal.org/ – GDAL and OGR are standalone tools for geospatial file
conversion. Difficult to use, but an incredibly useful (and free) tool for turning
GIS shapefiles and GeoTIFFs into KML. Rather than compiling GDAL, PC users
should install Frank Warmerdam’s FWTools binary package; Mac users should
install binaries from William Kingesburye.
Useful Data to Get You Started
http://www.gelib.com/usgs-topographic-maps-2.htm – USGS topographic maps (7.5’)
for the entire US.
http://www.geology.sdsu.edu/kmlgeology/index.html – Geological maps, particularly
of the San Diego region, from SDSU. Many of the maps are in vector form!
http://waterwatch.usgs.gov/?m=real&w=kml – USGS streamflow data in KML.
http://earthquake.usgs.gov/learn/kml.php – USGS fault and seismic data in KML.
Earthquake data include tectonic boundaries.
http://tinyurl.com/24rluy5 – Valery Hronusov’s time animation showing the
movement of Earth’s continents.
http://www.juiceanalytics.com/writing/census-data-in-google-earth/ – Basic census
data in KML form. gCensus (http://www.gcensus.com/) has more possible
aggregations.
http://serc.carleton.edu/NAGTWorkshops/structure/google_earth_mapping_locati
ons.html – Barbara Tewksbury’s set of locations for structural mapping.
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