Google Earth Introductory Guide and Tutorial

This is a brief guide for the standard, free Google Earth software.  It covers the basic functions you will need to complete the projects in your book.  Links are also provided throughout to the more complete Google Earth User’s Guide, located here: http://earth.google.com/userguide/v5/.

Google Earth (GE) is a spatial dataset interface available through the internet search engine Google and can be downloaded for free. This interface uses available aerial and satellite photographs at a variety of spatial resolutions overlain on digital elevation model datasets to give the images a three dimensional quality. Since this data is geo-referenced in all three dimensions, it can be used to make measurements of distance with the "path" and "line" measurement tools. Elevation, latitude and longitude are continuously tracked for any specific location of the cursor and are displayed at the bottom of the screen. GE also offers tools in the upper right corner of the screen that allow the user to zoom in and out as well as alter the azimuth and aspect.

One of the most recent functions of GE is the ability to move backward in time at some locations by accessing archived spatial datasets. In the spirit of all internet search engines, Google also provides a search window for transporting you to specific virtual locations. You may bookmark favorite locations as well as link locations to geo-referenced digital images taken at the same locations. Please make use of some or all these tools when getting familiar with the interface and have fun doing it!  Links to specific sections of the official Google Earth User’s Guide are included below.

USER INTERFACE
Get to know the main user interface for the software.

TOOLBAR
In addition to using the Search field, you will use the Toolbar in most of the Google Earth projects.

1- Term Search Field
2- Search
3- Hide/Show Side bar
4- Add a Placemark
5- Add a Polygon
6- Add a Path
7- Add an Image Overlay
8- Record a tour
9- Display historical images
10- Display sunlight
11- View Sky, Moon, or Planets                                             
12- Measure distance or area                                                                                                  
13- Email a view or image
14- Print the current view of Earth
15- Show the current view in Google Maps

NAVIGATION CONTROLS
These tools will allow you to change your position and your view of Earth.

SEARCHING
For the purposes of these Google Earth Projects, you will use the main search field to “Fly to” the location you desire. Tabs in this field also allow you to locate a business, or find directions to a location.

TRY IT: Search for your home or university.  Zoom in to see how close you can get. Use the directions tab to find directions from your home or university to the Grand Canyon.

LAYERS
Google Earth contains a great deal of information and locations available to users. Layers include businesses, landmarks, geologic features, borders and labels, and an ever-expanding list of content. These layers can be hidden by unchecking the box next to each layer, or they can be checked to be added to your view.

USING LINE AND PATH TO MEASURE DISTANCES
From the toolbar, you can select the Ruler icon to measure distances in a straight line, or multiple locations using the path tab.

TRY IT: Measure the distance from your home or university to the Statue of Liberty in New York City. Note that you may need to zoom in or out to be able to view both locations at the same time and get an accurate measurement.

USING THE HISTORICAL IMAGES TOOL
Click on the clock symbol in the toolbar to access a scrollbar that will allow you to move through images taken at different dates. The default within Google Earth will automatically display the most recent image, but you can scroll backwards in time to see the same location at dates in the past.  The accompanying image shows a park in Port-au-Prince, Haiti , twelve days after the devastating earthquake in January 2010. You can see the temporary shelters that had been constructed in a city park, not present in earlier images of the park.

TRY IT: What is the earliest image of your university campus? Can you see any changes on the campus between the earliest image and the most recent? Note you may need to zoom in to a close eye altitude to notice any changes. The eye altitude is located in the lower right of the screen.

Google Earth will automatically tilt your view of an object if you zoom in close enough. However, you can also tilt using your mouse.

• Be sure to check Terrain in the Layers pane.
• Depress the middle button or scroll wheel and move the mouse back and forth. If your mouse has a scroll wheel, you can tilt the view by pressing the SHIFT key and scrolling. You can also press Shift and the left mouse button and drag. Note that crosshairs appear and that your view tilts.
• Once you have tilted the view so that you are looking at a particular object, such as a mountain, you can also rotate around that object. When you do this, the object remains in the center of the view, but you look at it from different perspectives as you rotate around it.

Below are comparison views of Mount Everest.

Top-down view:

Tilted View:

TRY IT: Go to the Grand Canyon, or any mountain range, and experiment with tiling your view.