August 15, 2008
Google Earth is a representation of our planet as a globe
Google Earth is a geobrowser that presents satellite and aerial imagery, layers of information in vector format, search capabilities, the capability to present third-party data, and tools for creating new data. It represents the Earth as a three-dimensional globe that can be panned, rotated and zoomed. Data can be selected for viewing by controlling its visibility. Geobrowsers are also sometimes referred to as virtual globes or Earthbrowsers.
Google Earth also uses elevation data from by NASA's Shuttle Radar Topography Mission (SRTM). This is used to support a terrain layer, which can render landscape features in 3D, and to display the location of mouse pointer on the map.
Google Earth can represent structures such as buildings in 3D.
Google Earth is available in four levels of capability:
Free - Movie making
Plus - Higher resolution printing.
Pro - Movie making, importing ESRI shapefiles and MapInfo tab files.
All versions, including the free one, contain many useful capabilities for education.
Google Earth is available for:
Google Earth is easy to use.
Google Earth offers imagery for the entire world.
Google Earth offers a wide variety of interesting information in its standard layers.
Google Earth has a large dynamic user community that offers data and discussions for all to read and use.
Google Earth enables users to create their own data.
Google Earth can be used as 1) a platform for interactive inquiry-based activities for students in a computer classroom, 2) a presentation tool, 3) a means of creating images of portions of the Earth with vector data and overlays added to be incorporated into presentations, 4) a tool for researching many topics, and 5) a basis for student homework. It is best used with an internet connection because the imagery tiles and layers are stored on Google's servers, however, selected imagery can be cached in advance in anticipation of offline use.
Use Google Earth to help students learn about their local area. Find points in the layers that are located in the area.
When learning about a place in any subject area, look for points in the layers that are near that place. Look for relationships between subject areasto develop interdisciplinary thinking.
Prior to taking a school field trip, show the rout on Google Earth so the students develop conceptual geographic context for the landscape that they are about to travel. Look for layers that contain information on places along the route.
Vector data conists of points, paths, polygons, and three-dimensional models.
Overlays are georeferenced rater data.
Points (Placemarks) can respond to mouse clicks by displaying information balloons that contain text, images, hyperlinks, and other structures that can be implemented in html. Images can be embedded directly into kmz files or can be stored on a server, such as Flickr, and referenced as a hyperlink. There are advantages and disadvantages to each.
Google allows non-commercial personal use of the images created from Google Earth provided that copyrights and attributions are preserved. Works created by an agency of the United States government are public domain at the moment of creation. This means that those images can be freely modified, redistributed and used for commercial purposes.
The Google Earth toolbar contains tools that perform tasks related to the configuration of the user interface, the creation of objects to place on the map in the 3D View, a ruler for measuring lenths of lines and paths, showing sunlight in the 3D viewer, emailing a representation of the 3D View, printing the 3D View, and viewing the 3D View in Google Maps.
The Google Earth Toolbar
The Google Earth toolbar offers tooltips that pop up to identify each tool as the mouse passes over it. The Google Earth User Guide identifies the components of the user interface, and describes how to use them.
Adding a new placemark. While the New Placemark dialog box is open, the information inside can be edited and the placemark can be dragged to adjust its position.
Placemarks can be edited after they are created. Right-click (ctrl-click on the Mac) the placemark in the places pane or in the 3D viewer to open the Edit Placemark dialog box. While the dialog box is open, the information inside can be edited and the placemark can be dragged.
More information: Google Earth User Guide - Marking Places, Google Earth User Guide: Editing Places and Folders, and Google Earth User Guide - Using Places
Also see Google Earth Community: Placemarks and Overlays (Basic Training)
Creating a new polygon in Google Earth. Poins can be added, dragged, or deleted and the information can be changed while the New Polygon dialog box is open. The Edit Polygon box can be opened to alter the polygon after it has been created.
Google Earth User Guide: Drawing Paths and Polygons
Vector and features can be organized into containers such as folders and documents. Vector features can be assigned styles which in the case of points control color, opacity, size and the icon, and with paths and polygons, control color,opacity, and thickness of lines. Polygons can be filled or outlined.
Google Earth data consists of KML (Keyhole Markup Language) that can be saved in text format with a kml file extension, or, most commonly, in compressed kmz format with a kmz file extension. A kmz file is actually a zip archive which contains a doc.kml file with kml code, and possibly other supporting files such as images. The KMZ markup for a place or a container.
Google Earth can open several types of data files, including the standard kmz, kml formats, as well as images (jpg, bmp, tif, tga, png, jpeg, gif, tiff, ppm, and pgm), gps (gpx and loc), and Collada models (dae). In addition, Google Earth Pro can open additional formats, including ESRI shapefiles (shp) and MapInfo (tab) files. Once opened in Google Earth Pro, some of these formats can be saved as kmz files, which then makes them available to be used in the free version of Google Earth.
Many k-12 schools block sites such as Flickr that might contain comtent deemed inappropriate for young audiences. Those schools may chooses to enable teachers to store their hyperlinked images on theior servers. Alternatively, teachers may choose to embed their images directly in their kmz files, or assign homework that includes the use of kmz files that hyperlink images to external servers.
Many image hosting services ask that images used on web pages and in placemark balloons function as hyperlinks to the hosting service's web site in some manner. For example, Flickr requires that an image stored on Flickr that is displayed on a web page serve as a link to its Flickr photo page.
The Google Earth use interface consists of menus, tools, a search pane, a places pane, a layers pane, and a 3D viewer. When the panes list data, the visibility of each item on the 3D viewer can be controlled through toggled checkboxes. Folders and documents can be expanded or contracted through pluses and minuses displayed to their left. Data in the search and places panes can be reorganized through dragging, copying, cutting, and pasting.
Google Earth also features many layers as a source for information on businesses and points of interest, as well as showcasing the contents of many communities, such as Wikipedia, Panoramio and YouTube. Google updates with new layers so check them. Borders marks borders of countries, provinces and counties. Roads layer represents the road network for most countries. Google Earth Community layers contain placemarks that link back to the Google Earth Community posts where they were offered. The New York Times layer is acollection of news stories from the newspaper.
Google Earth also includes a built-in web browser. You can use this one or an external browser with Google Earth.
The properties of places, folders, and documents can be changed through dialog boxes, accessible through menus opened by right-clicking (ctrl-click on the Mac) the item in the panes or on the 3D viewer in the case of points. For points, you can create and use custom icons, for example see Google Earth Community: Eastern Box Turtles.
The ruler can be used to measure distances along lines and paths. In Google Earth Pro, it can also measure perimeters and areas of polygons, and radius, area, and circumference of circles.
Good examples of cities with buildings in 3D are Marvao, Portugal, Hamburg, Germany and Westport, Ireland.
Google Sky enables the user to look up at the night sky to view imagery of stars, galaxies and other features taken through powerful telescopes
Cambridge, Massachusetts in represented by high resolution imagery.
Google Street View provides 360° panoramic street-level photography for various cities and other locations.
Information balloon with photograph. The photograph is stored on Flickr and serves as a link to its Flickr photo page. See Google Earth Community Thread: Eastern Box Turtles. The placemarks on the map have a custom icon created from a photograph of an Eastern Box Turtle.
The code in the description box for this placemark is as follows:
<a href="http://www.flickr.com/photos/9428166@N03/2585372490/in/set-72157605646797812"> <img src="http://farm4.static.flickr.com/3041/2585372490_5851bd8eb2.jpg"> </a> <br></br> This female turtle was found crossing Whiskey Road in Ridge, NY on the evening of June 9, 2008. <br></br>The first line of code is the opening tag of a hyperlink to the photograph's Flickr page. The second line references the location of photograph on Flickr's server. On the third line is the closing tage for the link to the photograph's Flickr page. The third through sixth lines specigy a line break, the caption, and another line break, respectively.
There is an active official Google Earth Community that offers a set of forums. Anyone can join the community and post discussions and data to the Google Earth Community Forums. The Google Earth Community item in the Help menu of Google Earth can get you to the main index.
To register in the Google Earth Community you need to choose a username and password. You can then post to the forums by either starting a new thread or responding to an extisting post. Before issuing your first post, read the rules and look at other posts to learn how posting is usually done. Do not create a post that merely offers the same information as an existing one. The Community Forums can be searched, so before creating a post, find out whether the topic you plan to cover has already be adequately addressed in the Forums.
Age and resolution of the imagery varies. Most images are three years or less in age. Updates have sometimes resulted in shifts in the imagery.
Most land areas are covered in satellite imagery with a resolution of about 15 meters per pixel. Some population centers are also covered by aircraft imagery (orthophotography) with several pixels per meter. Oceans are covered at a much lower resolution by photography from by Terrametrics.
Google Earth is based upon latitude and longitude coordinates on the World Geodetic System of 1984 (WGS84) datum, therefrore GPS coordinates should be collected using this system.
Using GPS in Geoscience Education
Google Lat Long Blog is about Google Earth and Google Maps.
Using Google Earth Blog
Google Earth Cool Places
There are also other discussion groups and blogs devoted to Google Earth. A popular discussion group is Google Earth Hacks. A popular blog is Google Earth Blog.
Google Sketchup, another tool available in a free version from Google can be used to create three-dimensional models.
Google Earth User Guide
What is KML?
Google Earth Help Group
Google Earth Community: Any other college profs here who use GE in the classroom
Some uses for Google Earth in elementary school
SPACE: Virtual Globes in the Classroom
Google Earth Community Forums
Ron Schott’s Geology Home Companion Blog
Arctic Sea Ice Animation
Plate tectonics in Google Earth
San Andreas Fault Tour, 88 Places
World Crude Oil Refineries
All Scottish Windfarms operational or proposed
Long Island Pine Barrens
Thayer's Top 250 North American Birding Hot Spots
Google Search filetype:kmz "new york" - http://www.google.com/search?q=filetype%3Akmz+%22new+york%22
Google Earth and Geoscience Education
Uisng GPX data
How to use Flickr photos
Public School Issues
Google Earth API
Overlay example - hyperlinked or embedded
GEC: Educators Forums
GEC: Current Events
Discuss some of the layers
Only a couple of books have been written that are entirely or largely devoted to Google Earth.
Google Earth for Dummies: An introduction to using Google Earth and Google Sketchup.
Future of Google Earth: A boy and his grandfather's adventures with using Google Earth, with facts about cities an other locations on the Earth..
Terrain layer / elevation exaggeration
Geotagging photos GeoTagr
Discuss some GEC posts
Sources of data
Saving the view as an image
controlling transparency of overlays - transparency can be controlled by a slider in the overlay dialog boz or an slider in the places pane when the overlay is highligted inj the places pane.
touring paths and folders
Status bar lat-long etc
Google Earth Lessons
Mac and Linux differences from Windows
lat-long in sexagesimal or decimal degrees
tools options dialog box
detail area of 3D view
tabs in the search pane
Volcanoes Layer in the Gallery Layer
contrast with GIS
Google.org: New uses for Google Earth
Google Earth Outreach
Google Earth Community: Google Earth Outreach
Google Earth Sightseer
Google Earth User Guide: About Network Links
Google Earth Blog: The Google Earth Network Link
Google Earth Outreach: Using Network Links Effectively
An example of a network link: Education Tools. Assembling.
NASA World Wind
Microsoft Virtual Earth