Week 5: Monitoring Invasive Species

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Intro to ArcGIS

Opening Screenshot

ArcGIS is the market leader in geographic information systems for schools. Built to visualize, explore and analyze most forms of geographic data and remote sensed imagery, it is possible to combine point, line, polygon, and image data in ArcGIS. During the online course we will provide the data sets we want you to use to familiarize yourself with the interface. This spring and summer you will go through lessons with a large selection of comprehensive data that can be used in projects. ArcGIS can save and open projects, so work can be shared between users, or between school and home. ArcGIS classifies and symbolizes shapefiles, displays image data, works on data in several projections, and use data distributed over the Internet from several types of services such as ArcGIS online or any web based map service. It is also possible to use ArcGIS with data that is downloaded from a GPS unit to create custom layers of information that then can be related to scientific and other types of data. GIS Data is often freely available over the Internet from cities, counties and federal organizations such as the National Park Service (NPS) and the United States Geologic Survey (USGS) and many of the remote sensing sites we have already learned about.
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The ArcGIS Toolbar

The ArcMap toolbar contains a variety of tools for analyzing and manipulating geographic data. You will learn about the tools as you use them.

With the initial ArcMap startup, you will see a toolbar "floating" to the right.
Initial Screen

That toolbar can be moved and "docked" anywhere on the ArcMap interface. To move the toolbar, click and hold on the dark blue title bar at the top of the floating toolbar and drag it to the left or top of your screen.

The standard button bar contains a variety of buttons with different functions.
Standard Tools

The toolbar contains a variety of tools with different functions.

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Download Geographic Data About Invasive Species

  • Right-click on the PC or control-click on the Mac to download the zipped file below.
    Zipped file of Invasive_Species lesson and data (Zip Archive PRIVATE FILE 39.6MB Mar13 10)
  • Unzip the file. A folder called invasive_speciesAM will be created.
  • Move the entire Invasive_SpeciesAM folder to inside the WEEK5 folder of EYESINTHESKY2.
    The navigation path should be: C:/EYESINTHESKY2/WEEK5/Invasive_SpeciesAM

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Explore a GIS Map

  • Launch ArcMap by double-clicking its icon on your desktop or by clicking its icon in the Windows Launch Bar.
  • Choose File > Open, navigate to C:/EYESINTHESKY2/WEEK5 and select the file inv_spc.mxd. Then click Open.
    Opening Map ArcGIS
    When the project opens, a world map is displayed. Countries are shown in grey and lines of latitude and longitude are drawn at 30 degree intervals.

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Zoom in and out

  • Use the Zoom In Zoom In tool to click once on South America.
  • Click once on the Zoom to Full Extent tool Zoom to Full Extent to take the map all the way back out to a full view.
    NOTE: This is a nice trick if you get lost and just want to start over again.
  • Continue clicking on the map with the Zoom In Zoom In tool. The tool centers the map at the area where you click. How far can you zoom in?
  • As you zoom closer and closer on image (raster) data, you eventually see "pixels," however, vector based data can be zoomed in infinitely without seeing pixels.

    The reference numbers in the scale box at the top of the map are the scale of the map represented as a ratio or a fraction. They refer to the level of magnification. At the maximum zoom you see 1: .01 a ratio. In other words, 1 inch on the map would be equal to one hundredth of an inch in reality. As you zoom back out, watch the numbers in the ratio change. When you zoom back to full extent, the scale reads 1:191,512,364. So this means that 1 inch on the map represents 191,512,364 inches, or approximately 3,000 miles.

  • Use the Zoom Out Zoom Out tool to zoom out several clicks. How far can you zoom out?
  • When you are done exploring zooming, click the Zoom to the Full Extent Zoom to Full Extent tool.
  • Click your left mouse button and while holding it down, drag out a rectangle across Africa with the Zoom In Zoom In tool. Notice how this allows for more precise zooming.
  • Click the Zoom to the Full Extent Zoom to Full Extent tool to return to the full map view.
  • Likewise, you can also use the Zoom Out tool to drag out a box. It is possible to keep zooming out until all you see is just a tiny speck or your map even disappears. Sometimes this might happen unexpectedly, especially if you click and drag out a tiny box with the Zoom Out tool. Try this. Then, experiment zooming in and out so you get a feel for how this works.
  • Click the Zoom to the Full Extent Zoom to Full Extent tool to return to the full map view.
  • Two other buttons help you navigate on screen. They are the Previous Extent Previous Extent and Next Extent Next Extent buttons. Try zooming in and then experimenting with these buttons. The Previous Extent button lets you go back to a previous zoom level. Both of these buttons give you unlimited zooms back and forth between levels.
  • When you are zoomed in, you can use the Pan Pan tool to adjust your view. Click and hold the Pan tool and drag your mouse to center your map on another place.
  • When you are done exploring zooming, click the Zoom to the Full Extent Zoom to Full Extent tool.
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Find latitude and longitude

Move the cursor across the map to discover changes in X and Y and how they relate to Longitude and Latitude.

  • Start at the far left side of the map and move your cursor horizontally to the right all the way across the map. Observe how the X coordinate changes. The X and Y coordinates are shown in the lower right corner of the map. What happens to the X values?
  • Move your cursor vertically from the bottom to the top of the map and observe how the Y coordinate changes. What happens to the Y values?
  • Which values are longitude? Which are latitude? How are south and west indicated?
  • Just for fun, try to find 0, 0. (Hint: it is near Africa)
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Discover How the Layers Build the Map

A GIS map — is made of layers of geographic information connected to specific places on Earth. GIS layers can be global, regional, or local. They can represent 1) points, such as cities, 2) lines, like rivers and roads, or 3) geographic areas such as states and countries.

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Turn layers on and off

To turn a layer on or off, click in the check box next to the name of the layer. The layer will then be displayed on the map.
  • Click the checkbox next to the US States layer to turn it on.
    States Turned On

  • Currently, the legend of the US States layer is expanded so that the name of every state is displayed. To collapse the legend, click the minus symbol to the left of the layer checkbox. Then use the Zoom In Zoom In tool to zoom in on North America by clicking on the map.
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Explore moving Layers in the Table of Contents

  • Click the Zoom to the Full Extent Zoom to Full Extent tool.
  • To the left of the map space is a listing of Layers, called the Table of Contents.
    • In the Table of Contents, select the Countries layer by clicking and holding its name. Drag the Countries layer down the list and place it at the bottom of the Table of Contents.
    • What has happened to Countries layer?
    • Turn off the Lat / Long Layer and you will be able to see Countries again.
    • Turn the Lat/Long layer back on. Click and drag the Lat/Long layer to the bottom of the Table of Contents.
    The data that make up the layers are shown as either points, lines, or polygons. These layers come from shapefiles, a standard GIS data format. (It is also possible to add images to a GIS.) The layers are drawn from the bottom to the top as they appear in the Table of Contents. If not positioned properly, it is possible for some layers to cover up others. In general, polygons should be placed at the bottom, while lines and points should be arranged near the top.

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    Understand Which Layer You Are Working With

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    Select a layer

    ArcGIS allows you to choose which layer you want to work with from within all tools. If you are asking to find a certain river in your project, just make sure that you choose the rivers layer to look in when asking the software to find the Pearl River for instance. This is the equivalent to making a theme active in other versions of GIS software. This should help simplify the concept of whether a layer is visible or if it is active which is required in other GIS packages. Layers that are turned on or are visible have a check in the box next to their name. More than one layer can be on at a given time, don't forget that some layers can be on top covering other layers when looking for them. Feel free to rearrange the layers to avoid completely covering over as needed.
    Turn on the US Rivers layer.
    • To turn on the US Rivers layer, click once in the box next to its name.
    • Zoom to Active Layer

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    • Zoom to the US Rivers Layer.
    • To zoom in on the US Rivers layer, place your mouse over the US Rivers layer and click the right side of your mouse, Choose Zoom to Layer in the window that opens.
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    Investigate the Geographic Data Behind the Map

    What sets a GIS apart is the database of information linked to each layer drawn on the map. This makes it a powerful tool for decision-making and science. The data for each feature displayed on the map can be found in the Attribute Table. This table, or database, contains the geographic records in horizontal rows. The vertical columns, or fields, are the attributes of the data.
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    Examine the Data in the Attribute Table

    Select several US Rivers to connect rivers with their river systems.

    • With the US Rivers layer turned on, right-click on the US Rivers layer in the Table of Contents. Then select Open Attribute Table.
    • In the Attribute Table, click the left most column of the table to select the record on for the NAME Arkansas River. Notice it becomes highlighted in blue in the Table of Contents and in yellow on the map.
    • Try this with several rivers. The Attribute Table brings up the records of all the rivers and shows you all the information that is available for each record. For example, you can see which river system various rivers are in. The Arkansas River is in the Colorado River System.

    Select all the rivers in the Colorado River System.

    • Open the Attribute Table of US Rivers and right-click on the column that holds the data for the field header entitled SYSTEM. Then select Sort Ascending, scroll down the list to where you see the 4 rivers on the map that are in the Colorado System.
    • Hold the shift key and click on the first and last of these 4 rivers to select the rivers as a group.
    • Once you have made several selections, close the Attribute Table and click on the Clear Selections button. Clear Selected
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    Find Features of Rivers With The Identify Tool

    Find rivers on the map with the Identify tool Identify

    • Click on the Identify tool in the toolbar to select it. Use the Identify tool to click on a river on the map to select it. In the pull down menu select the US Rivers as the layer to "identify from:". The selected river will flash green and a results window will open.
    • Click on several US Rivers to identify them.
    • At the end of your sesssion, quit ArcGIS. Do not save changes that you have made to the map.
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    Explore More if You Have Time

    Explore the Attribute Tables of other layers in the map to see the different types of data linked to the map layers.

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    Additional ArcGIS Resources
  • Instructional Materials for ArcGIS
  • Getting started with GIS
  • Download documentation for AEJEE
  • Geospatial Technology Curriculum Page
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    Movies on this Page

    Note: 3/15/10 The movies in the page above are ArcGIS movies. AEJEE movies are posted below.

    How to download movies

    • Click the link to go to the SERC media library listing for the movie. The record will open in a new window.
    • On the SERC media library page, right-click (Win) or control-click (Mac) the link (below the movie on the Flash version pages) to download the movie file to your hard drive.

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    Flash Video Versions

    Download these versions to play on your computer. You'll need an appropriate movie player to view the file, such as Flash Player, Real Player (Mac / Win), or Adobe Media Player.

    Movie Icon Zooming ArcGIS

    Movie Icon Latitude and Longitude ArcGIS

    Movie Icon Layers ArcGIS

    Movie Icon Zoom to Layers and Layers On and Off ArcGIS

    Movie Icon Investigating Database ArcGIS

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    iPod Versions

    Download these version to play on your iPod or iPhone.

    Movie Icon Zooming ArcGIS

    Movie Icon Latitude and Longitude ArcGIS

    Movie Icon Layers ArcGIS

    Movie Icon Zoom to Layers and Layers On and Off ArcGIS

    Movie Icon Investigating Database ArcGIS