Lab Exercise #3 Introduction to the Digital Globe Google Earth Geo210 Rockland Community College Professor Paluzzi Due Date: The Digital Globe: Google Earth 30 Points Purpose: This lab will introduce the concept of the Digital Earth. The intended goal of all of the module s learning activities is to demonstrate to students how useful it would be to spatially represent data and imagery on virtual globes and computerized maps (computer/digital cartography). In addition, the student will learn fundamental concepts of geospatial analysis. Equipment & Materials: Google Earth, Web browser with high-speed Internet Access. Installation instructions are included at the end of this document. Instructions: Read the explanatory materials and complete the questions that follow. What do you need to turn in? There are a series of imbedded questions (clearly labeled) within this document. In order to gain credit for this exercise, you need to turn in the answers to these questions and the appropriate screen shots (ALT+PRNT SCRN key will copy the screen to the clipboard. Edit->Paste or Ctrl+V will paste the screenshot into your Word document. The document should be submitted in Word format, Text format, RTF format, or a.pdf file. Getting to Know Google Earth Google Earth is a friendly 3D, Internet-based Geographic Information System (GIS) application. This application was originally developed by the Keyhole Inc. located in Silicon Valley. In 2004, Keyhole Inc. was acquired by Google. Google re-packaged Keyhole s 3D Virtual globe software and released a new version called Google Earth in June, 2005. The concept of the Digital Earth was unveiled to the general public by Google Earth; many researchers or governments agencies started to utilize Google Earth for their work. The software enables you to virtually fly over any place in the world from your computer. By the publication of this document, Google Earth 5.2 has been released, which allows users to freely incorporate uploaded GPS points of data onto baseline maps. The program, therefore, is becoming much more than bells-and-whistles. As Google Earth becomes more and more robust, it is trending from a 'fun', casual tool to one that is being used in classrooms and in research labs alike. The following set of instructions will provide users with some of the varied uses of Google Earth. Open Google Earth via the short cut icon on your Desktop or via the 'Start' button: Click on the Google Earth icon on your desktop, or Use the Start button (Start > All Programs > Google Earth > Google Earth).
Now, let's learn about Google Earth s basic features and controls. Figure 1-1: Google Earth Primary Map Controls and Functions There are three operational panels (see 1, 2, and 3 in Figure 1-1), Navigation Control (4), and a map view (5). The three panels are the Search Panel (1), the Place Panel (2), and the Layer Panel (3). Go to the "View" pull-down menu and toggle on the "Overview Map" by clicking on the option from the pull-down list. You should now see a world map pop-up on the bottom right corner of the screen. You can remove this world map by de-selecting "Overview Map" from the View pull-down menu. The Navigation Controls (4) include the following: The Look Joystick control : Use the Look joystick to look around as if you were turning your head. Click an arrow to look in that direction or continue to press down on the mouse button to change your view. After clicking an arrow, move the mouse around on the joystick to change the direction of motion. Click and drag the globe and move around. Notice the way the Look Joystick moves. The Move Joystick control : Use the Move joystick to move your position from one place to another. Click an arrow to look in that direction or continue to press down on the mouse button to change your view. After clicking an arrow, move the mouse around on the joystick to change the direction of motion.
The Zoom Slider : To get closer to the ground to see more detail but in a smaller geographic area. Try to clicking and dragging the slider toward the plus/minus sign; try double-clicking on any part of the image. The Hider/Show Sidebar : and Layers panels). To conceal or the display the side bar (Search, Places The Add Placemark control : To add a placemark for a location. The Measure control : To measure a distance or area size. The Add Overlay controls : To create and add your own overlay features onto Google Earth. You can draw a polygon, a path or line, add a graphic image, or record a tour to the map which Google Earth will drape over the terrain. 5 : Enables you to view historical imagery. Drag the time slider to change the imagery to other acquisition dates. : Allows you to set sunlight across the landscape. Just slide the time slider to the time of day you wish to display the desired amount of daylight upon your landscape. Email : To send the current view to a user with Google Earth or send an image of the current view to an email recipient. Print : To print the current view of Earth. : To show the current view in Google Maps in your web browser.
: A switch press between sky and earth. Click it to view stars, constellations, galaxies, planets and the Earth's moon. This is a great feature, especially for astronomical applications (you can even set up a Google planetarium). Search Panel (1): Type San Diego in the Fly To address field and then press the enter key. This will fly you to the center of downtown San Diego, CA. Layers Panel (3): Next, we are going to introduce an important concept in GIS called, Map layers. Map layers are layers of map features, data, or imagery that can be overlaid or stacked together like layers on a cake or toppings on a burger. LIST OF LAYERS Figure 1-2: List of Layers From the "Layers" window, turn on the Primary database and expand the list. Select the following data layers to display: Places, Roads, and 3D Buildings features by clicking on the box next to the name (Figure 1-2). Now, even though you have turned on some layers, their associated features may not be visible. You must sufficiently zoom in to the area to see the features. This is called "scale-dependent features". It should not make sense to show all the buildings on the map when you are zoomed out all the way. Google Earth and other virtual Earth-type applications make features like roads and buildings visible only when they would be visible in real life. Play around, see what you see. Fly to an area of your choice and paste a screenshot above question #1. Explain briefly what we are seeing. Next, answer the following question: Question-1: Fly to Balboa Park in San Diego, CA (type in "Balboa Park" in the "Fly to" window). There are a variety of highlighted points on the map (colored squares and blocks that green, blue and yellow), click on some of these points and answer the following question: What type of information does each thematic point provide and who provides this information (Note: You can expand the Primary Database layer by
clicking on the "+" sign next to "Geographic Web" You can now expand "Places" and "Preview"...this immediately shows some of the power of Google Earth. Data is being input into the system from a vast array of sources.)? Try experimenting with some of the other layers. If you click on "Traffic", real-time traffic data will appear on your map (if you are zoomed in sufficiently close). If you click on one of the real-time traffic dots, you will get average speed data of that strip of highway or road. Include a screenshot of Balboa Park. Exploring the World: Examples of 3D Viewing a) The Grand Canyon: Fly to the Grand Canyon by Entering Grand Canyon in the Fly To Address Field. Zoom in and change the look angle from vertical to closer to ground level. This will show 3D terrain. Press enter. (See Figure 1-3) Click on the Look Joystick and/or use the "Zoom slider" controls until you see the terrain from slightly above ground level (Figure 1-4). Explore the local area with your Navigation controls. You can move around (pan) and zooming in and out. Now, click on the "Tools" pull-down menu. Select "Enter Flight Simulator". Select your aircraft (I recommend the SR22, as it is easier to fly than the F16). If you click "Help" to get a list of controls, you will have to enter the flight simulator again via the "Tools" menu. Here are some quick directions: the "Page Up" button will thrust you forward, and the arrow keys will move you around. Now, click "Start Flight" (note: while you are flying, you can then click the "Help" pull-down menu for the flight instructions). Enjoy the flight over the Grand Canyon! Use your mouse cursor (see arrow in Figure 1-4B) to control your flight.
Figure 1.4B b) Downtown San Diego: Now that you have crashed a few times, you can exit the flight simulator...fly back to downtown San Diego, CA by typing in "San Diego, CA" in the "Fly to" window. In the Layers window, make sure that "Roads", "3D buildings", and "Borders and Labels" are clicked on. Now zoom in, zoom out, and tilt to explore downtown San Diego (Figure 1-5). Next, answer the following question: Question 2: After touring the Grand Canyon and downtown San Diego, write down your opinions regarding the usefulness of different functions like Roads and 3D Buildings. Clearly, there are applications in tourism that one can think of right away. What applications can you envision with regards to scientific studies, for example?
Now that you are familiar with several of the Google Earth navigation tools like Zoom In, Zoom Out, Tilt, etc.. Use these tools to explore the entire globe. Explore your home town. You can even type in your address in the "Fly to" window to see your home from above (not to mention at street level). Question 3: Describe what you see regarding your home. Typically we see our home through a very oblique (eye-view) perspective. How does the impression of what you see change when viewing it from above? Like before, include a screenshot of your home. Latitude & Longitude A Quick Review of Latitude and Longitude To locate any unique point on Earth, a coordinate system must be used. Google Earth and many other applications use the geographic grid system of latitude and longitude. Latitude: Latitude describes an imaginary survey line which runs east to west. You can think of these parallels of latitude as forming the rungs on an imaginary ladder. Latitude is expressed as an angle from 0 to 90 degrees either north or south of the Equator (See Figure 1-6). Figure 1-6: Latitude As we discussed earlier, latitude is the angular measure north or south of the equator. In the Decimal Degrees system, it is important to note that when you are going north of the Equator the values range from 0 to 90 degrees in the positive direction. Think of this as going up on the imaginary ladder starting from the Equator. If you go south of the Equator the values range from 0 to -90 degrees. Think of this as going down the imaginary ladder from the Equator. As an example, Sydney, Australia lies at approximately -33.87 degrees Latitude (note the negative sign). Anchorage, Alaska lies at approximately 61.22 degrees Latitude (note the positive value). "-" is the same as "south" and "+" is the same as "north". Longitude: Longitude is the angular measure from the Prime Meridian. Longitude describes an imaginary survey line running south to north. There are 360 degrees of longitude and they all converge at the North and South Poles. Longitude is expressed as an angle from 0 to 180 degrees either west or east of the Prime Meridian (See Figure 1-7). The Prime Meridian is the imaginary line that extends from the South Pole to the
North Pole and passes through Greenwich, London, England. It is described as 0 degrees longitude. In the Decimal Degrees system, it is important to note that when you are going west of the Prime Meridian, the values range from 0 to -180 degrees; you are going in the negative direction. When you go east of the Prime Meridian the values range from 0 to 180 degrees; you are going in the "positive" direction. At 180 degrees longitude, you reach the International Date Line. Here, there is no positive or negative. This imaginary line runs from the South Pole to the North Pole in the middle of the Pacific Ocean and is on the opposite side of the Earth from the Prime Meridian. As an example, Sydney, Australia, which is in the Eastern Hemisphere, lies at approximately 151.21 degrees longitude (note that it is a positive value). Anchorage, Alaska, which is in the Western Hemisphere, lies at approximately -149.89 degrees longitude (note the negative sign). "-" is the same as "west" and "+" is the same as "east". 0 degrees longitude (the Prime Meridian) is neither + nor -. The International Date Line (180 degrees longitude) is neither + nor -. Decimal Degrees: Latitude and longitude are most commonly expressed in Degrees, Minutes, and Seconds or Decimal Degrees. Both are equivalent. However, for the sake of simplicity, we are going to use Decimal Degrees. In order to view the map coordinates in decimal degrees, you will have to make a change in Google Earth. First, select the Tools pull-down menu and click on Options The Google Earth Options menu will appear (Figure 1-8). In the Google Earth Options menu, be sure the 3D View tab is selected and change the Show Lat/Long option to Decimal Degrees (Figure 1-8). In this case, the latitude (y-coordinate) and longitude (x-coordinate) will be represented in decimal degrees. This is how most GIS and related software applications represent latitude and longitude. Save the settings by clicking on the OK button. Figure 1-8: Google Earth Options Menu with Degrees Selected for Latitude and Longitude in the 3D View Tab
Figure 1.8A shows Degree Minute Seconds representation of Lat/Long. After changing the settings, as above, the same location is depicted in Decimal Degrees (Figure 1.8B below). Figure 1.8A Figure 1.8B Your Home Address Now let's determine the Decimal Degrees of your home. a) In the "Layers" window, be sure the borders and roads features are on. b) Enter the full address of your home in the "Search" window (for example, the address of Rockland Community College is: 145 College Road, Suffern, NY) c) Determinie the latitude and longitude of your home by moving your cursor over the center of your home in the Map View window. Coordinates will appear in the bottom of the screen (Figure 1-9 below). Figure 1-9: Latitude & Longitude Coordinates of Rockland Community College, 145 College Road, Suffern, NY) After you determine the coordinates of your home, create a Placemark for it: a) With the use of the Navigation Tools, position your home near the center of the screen.
b) Click the Add Placemark button: It is located near the top of your Google Earth window. A New Placemark control panel will pop-up and a Placemark will appear near the center of the screen (indicated by the black arrow in Figure 1-10 below). c) Grab the Placemark by clicking on the Placemark. Now, drag it to the center of your home. d) In the "Name Field" (see Figure 1-10) type in a name for your home. Before you press the OK button, click on the View tab in the New Placemark control panel. Record the following information: Question 4: What is the "name" of your home (that is, what did you title the Placemark)? Question 5: What is the Latitude of your home? (decimal degree & Degree Minute Seconds) Question 6: What is the Longitude of your home? (decimal degree & Degree Minute Seconds) e) Click on the OK button to save the new Placemark of your home on the map. When you Zoom Out, the new Placemark for your home will remain visible. Now, let's determine the distance between your home and Rockland Community College. In the Search address window enter the address of Rockland Community College: 145 College Road, Suffern, NY.
Create a new Placemark for Rockland Community College (Note: the pointer might be slightly off. Please put a Placemark on one of the buildings on the campus -- see Figure 1-10 above). Zoom out enough so both Placemarkers are visible (your home and RCC). You should be able to do this even if your location is in another state or country. Open the Measure Tool control, which is located in the Tools pull-down menu, or, click on the Measure icon: (note: it might also be called Ruler depending on which version of Google Earth you are using). Use Miles as your measuring unit. Click on your home, then drag the line to the SWC Placemark. Double-click on RCC. (Figure 1-11) Question 7: What is the distance between your home and RCC (miles): Now, close the Measure Tool by clicking on the X on the top right-hand corner of the Measure Tool menu. Now let's create street map directions between your home and SWC. Go to your home Placemark. Right-click on top of it (MAC users, hold down the Control button and mouse Click). A pop-up menu will appear. Select the Directions from here option. Next, go to the RCC Placemark. Right-click on top of it. Select the Direction to here option. Google Earth will automatically create direction between your home and RCC (see Figure 1-12). Play Tour If you click the "Play Tour" button, you will have a virtual street by street drive-through all the way to RCC... Please answer the following question:
Question 8: What is the first step of driving instructions that Google Earth lists FROM your home (just copy down the first one)? Figure 1-12: Generating Turn-by-Turn Navigation Instructions Some Additional Fun Exercises: a) Area 51 is a Top Secret U.S. Military site (in Nevada) that many in the government claim does NOT exist! The coordinates are 37.249361,-115.812339. Copy the coordinates into the Fly To address field and click enter. Question 9: What does Area 51 look like to you (i.e. a shopping mall? a lake? an airport? etc.)? Describe in detail what you are seeing. b) Next, in the "Places" window, double-click your home Placemark (you will automatically be taken back to your home). Now, let's figure out the name of the nearest pizzeria. Hint: Make sure your home is near the center of the screen then Select the Find Businesses tab located next to the Fly To tab (Figure 1-13). Enter "Pizza" in the What field then press enter. Use the Measure tool to determine how far away the nearest pizzeria is from your home. Question 10: What is the name of the nearest pizzeria? How far is the pizzeria from your home (in feet)? Include a screenshot.
Figure 1-13: A Local Search of Pizza Restaurants c) Alcatraz Island, near San Francisco, California, used to be an inescapable highsecurity prison where the worst and most notorious criminals were kept. The island, known as The Rock is surrounded by dangerous currents and freezingcold water. It was supposed to be nearly impossible to escape! Using Google Earth, answer the following questions: Question 11: In what general direction (north, south, east, or west) is the city of San Francisco located relative to Alcatraz Island and how far apart are they from one another (Hint: use the Fly To field and type "Alcatraz". Next, use the Measure tool)? Question 12: What is the least distance that someone needs to swim in the ice-cold water to escape the prison island? Question 13: In what direction is the Golden Gate Bridge relative to Alcatraz Island (Hint: if you are uncertain where the Golden Gate Bridge is, then type in "Golden Gate Bridge" in the Fly To window. Also, be sure the "3D Buildings" is on in the Layers window)? Above your answer to question 14 post a screen shot of Crater Lake, OR. Question 14: Now that you are familiar with some of the functionality of Google Earth you are to navigate to 5 different locations in Rockland or Orange County. Interpret the image from a geographic perspective. For each of the five locations provide the place you are identifying and describe what you see. You need to include a screen of the location, and you must interpret both the cultural and physical landscape of each location.
Place 1: Place 2: Place 3: Place 4: Place 5: