CE 547 - GIS in Water Resources Engineering

Assignment #2

CE 547, Spring 2009

 Due Wednesday, February 11

Below, I provide a framework for you to become more familiar with the ArcMap environment.  The assignment uses shapefiles for the counties of New Mexico and for pan evaporation stations in New Mexico.  This assignment has similarities and was originally based on one Maidment uses in his course with data for Texas.

 Use ftp to get the necessary shapefiles for this assignment from the cegis account. 

  From the Start Menu and Programs, Open ArcMap.  You want to start with “A new empty map” as shown below.

 
 
From the toolbar, select the Add Data button.  Notice that if you hold your mouse over various buttons, you will be the told their name.

After depressing the Add Data button        , you will get the Add Data dialogue box. 

 
Navigate to the folder that you have placed the shapefiles in.  Note that both shapefiles consist of three files and if all three files are not present, you will not get the *.shp file in the Add Data dialogue box.

Note that if you access the File Properties (click File on the menu toolbar and select Properties), you will have the option to make the data source be either an 'absolute' or 'relative' file name.  If you use a relative file name, you will alleviate some of the issues associated with using your USB drive in different computers that assign the USB drive different letters.

Once you’ve added the data, you will be able to see the shapefiles in your view and the names of the shapefiles in the Table of Contents.  Note that you can use the checkmarks in the Table of Contents to make layers turn on and off.  Also note that you must have the points (NMevap) on top of the polygons (newmexico).  Turn the layers on and off and change the order in which they appear to make sure you understand these basics.

 ArcMap uses the right click of the mouse to access a number of commands and tools.  For example, within the Table of Contents, select the name of the ‘data frame’ which by default is “Layers”.  Once selected, right-click the mouse, and the following drop-down menu should appear.  Select Properties to change the name of the data frame.

  Note all of the tabs that are available in the Data Frame Properties.  Change the Name under the General tab, but take some time to browse through the other tabs.

Let’s “play” with the way our layers appear in the Data Frame.  Use the mouse to double click the symbol (in the Table of Contents) that is being used for NMevap.  The Symbol Selector window will appear.  Near the bottom right of the window, click More Symbols and check out some of the additional symbols you can use.  I chose the Environmental list.

 Once you’ve added additional symbols, you should be able to see them in the Symbol Selector.  I chose “Droplet, Water.”

 Then I changed the color of the water droplet by pressing Color under Options, just to the right of the symbols.  We can also change the appearance of our other layer which has polygons.  Once again, double-click the polygon in the Table of Contents in front of the layer name to bring up the Symbol Selector window.

ArcGIS is "smart" and knows that you have polygon instead of point, so this is reflected in the Symbol Selector.  You have the option to change the fill color and the outline color here.  You can also select Properties.  Another way to get to the Layer properties is to right-click on the layer name within the Table of Contents.

 I selected categories so that I could show each county in a unique color.  Take some time to play with the different ways the data can be shown.

 Next, let’s open the attribute table associated with the pan evaporation data.  Right-click the layer NMevap.

 Select Open Attribute Table from the Pulldown menu.  The table should appear and you should be able to scroll through the table to get an idea of the attributes associated with this shapefile.  Next, we’ll select several features using the Select Feature Tool.

This tool allows us to select feature in the view.  I’ve use the tool to select three pan evaporation sites.  Simply depress the shift key while using the tool. 

Note that the features that are selected correspond with the records that become selected in the attribute table.

At the bottom of the table, you can choose to just have the selected records shown.

Also, at the botton of the table is an Options menu which allows for a number of table functions.  We’ll use these functions to create a graph.  Alternately, you can go to Tools>Graph>Create.

  The Graph Wizard will appear.  Below are steps of the Graph Wizard in 9.2.  The Graph Wizard in 9.3 is different but should be easy to follow.  You might also want to refer to refer to Chapter 11 in the green book which includes a brief exercise on graphing.

In the first step of the 9.2 Graph Wizard, choose a type of graph.  I chose a column graph.

 In the next step, you need to choose a Field to graph.  I chose annual evaporation.

  In Step 3, you can choose Advanced Options to get a number of tabs that you can experiment with to see how you can change the appearance of your graph.

Just above the Advance Options button, you can check to “Show Graph on Layout”.  If you check this box, you will automatically be switched to the Layout frame.  In the Layout Frame, you can play with adding a number of objects to your layout that could then be printed or copied to a presentation.  Once again, you can use your right-clicker.  This time you’ll get the option to Copy.  You can then Paste into another application.  To save space in Word or Powerpoint, use the Paste Special from the Edit pulldown menu so that you can paste your object as a picture.

Be creative with this assignment and see if you can create a layout that “tells a story” about pan evaporation in New Mexico.  Print the layout and post the layout on your webpage.  Also turn in a brief explanation of what you did and any major difficulties that you had.  Have fun (I hope!)