1. Start ArcMap by going to the Start menu > All Programs > ArcGIS > ArcMap.

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1 Learning ArcGIS: Introduction to ArcMap 10.1 The Map Document Feature Manipulation Navigating ArcMap Map Documents, Layers, and Features Shapes, Location, and Attribute Data Symbology Zoom, Pan and Map Scale Finding, Measuring, and Identifying Features Estimated Time: 1 Hour ArcMap ArcMap is a module of ArcGIS that allows you to investigate, manipulate, analyze and create spatial data. ArcMap allows you to create maps using any number of dataset combinations. This is the application you will probably use most frequently to create new datasets, maps, and analysis for your project. The Map Document In ArcMap, a map document is a file containing a map and display properties. Map documents are constructed using various data but do not contain the actual datasets themselves. A map document is just a text file that contains the path to your GIS dataset. You create, edit and analyze data in ArcMap, and the map document allows you to save the unique combination of data and symbology that you are working with. When you delete a map document, you are only deleting this combination of data and symbology, not the actual data records. 1. Start ArcMap by going to the Start menu > All Programs > ArcGIS > ArcMap. 2. Click the Open button. 3. Navigate to the tutorial data folder provided to you and double-click SouthSanFrancisco.mxd. 1

2 Data Frames and Layers The SouthSanFrancisco map shows San Mateo and Santa Clara counties. The SouthSF map is made up of layers that show various geographic objects. In the Table of Contents (TOC) you will see a data frame icon with the name South San Francisco and a list of layers underneath. Geographic features are displayed as a layer. A layer is a collection of features of the same geometry type (fig. 1). The geometry type used to represent an object depends on the amount of detail that needs to be shown the same object may be represented as a polygon in one layer and a point in another layer. A city, for instance, could be represented as a point with a unique location in a country or as a polygon with a boundary and an area. 2

3 Figure 1: Conceptual diagram of map layers; Table of contents from San Francisco Bay Area Map. In this map, there are 7 layers showing in the TOC: Redwood City, Highways, Major Roads, Cities, Counties, Block Groups and California (fig. 1). Redwood City is a group layer; expand its drop-down menu to see the additional 6 layers that it contains (signs, bike routes, roads, crosswalks, city parcels, and school districts). You can turn layers on and off in the display by checking and unchecking them in the table of contents in the box left to their names. 1. Take a look at each data layer by turning them on and off in the table of contents. You may notice that the Redwood City Signs and Parcels layers do not display. The corresponding check boxes in the TOC are grayed out indicating that these layers are not set to display at this scale. When you turn on the Major Roads layer, the roads do not show up in the two counties. This is because they are located below the Block Groups layer in the table of contents. The order of layers in the table of contents dictates the order that ArcMap displays each layer. 2. Select the Major Roads layer by clicking on it once. Drag it above the Counties layer in the table of contents so you can view the roads layer. 3

4 Features Have a Shape, Location and Attribute Data Layers are collections of geographic objects or features. These features are represented in a GIS as one of three geometrical forms: a polygon, a line, or a point. Every spatial dataset has to have a coordinate system 1 in order to be correctly displayed in ArcGIS. If it s a geographic coordinate system 2, its features store latitude longitude values (in degrees). If it s a projected coordinate system 3, its features store x,y coordinates in linear units (meters or miles). When you first add a layer to an empty data frame in ArcMap, the data frame displays the layer according to the coordinate values of its features geographic and/or projected. You can find information about an individual layer s coordinate system in the Layer Properties window. 3. Right-click California State Boundary in the TOC and select Properties. 4. Go to the Source tab and review the information under Data Source. Here you will find the spatial information associated with this layer. Note that the Coordinate System is NAD_1983_StatePlane_California_III_FIPS_ Explore the other tabs in the Layer Properties window. This window provides you with both information and tools to work with the data. We will explore some of this functionality later in this tutorial. Close the window. As you know from ArcCatalog, features can be linked to all types of additional information, and this information is stored in an attribute table. Each row in the attribute table corresponds to a single feature, and each column (field) is a category of additional information. 6. Right-click Cities Study Area in the TOC and select Open Attribute Table. Notice the many fields in this attribute table. You can scroll to the right and/or resize the attribute table window in order to view more fields. 1 A coordinate system is a reference framework consisting of a set of points, lines, and/or surfaces, and a set of rules, used to define the positions of points in space in either two or three dimensions. The Cartesian coordinate system and the geographic coordinate system used on the earth's surface are common examples of coordinate systems. 2 Latitude and longitude are the basis of a geographic coordinate system, a system that defines locations on the curved surface of the earth. Latitude and longitude are measurements of angles, not of distances. Latitude is the angle between the point you are locating, the center of the earth, and the equator. Longitude is the angle between the prime meridian, the center of the earth, and the meridian on which the point you are locating lies. Their values are expressed in degrees, minutes and seconds. 3 A projected coordinate system defines locations on a flat map and is based on x y coordinates. The intersection of the axes is called the origin. Feature locations are specified by their distance from the origin in meters, feet or another unit of measure. 4

5 7. There are a few ways to sort the information in this table. Right-click on the NAME field heading and note the options provided in this menu. Selecting Sort Ascending will sort the field alphabetically, A-Z. You also have the option to Sort Descending, from Z-A (fig. 2). Figure 2 You can also freeze a column to ease the reading of the table. Freezing a column in the Attribute table is similar to freezing or locking a column in an Excel spreadsheet: it keeps specific columns visible while you scroll in the table or worksheet. 8. Right-click on the field name at the top of the column and select Freeze/Unfreeze Column. Now that this column is fixed, find the size of Belmont in square miles (Hint: scroll to the right until the attribute field SQMI fits right next to the field NAME and scroll down until you find Belmont). How does this value compare to the sizes for Redwood City and San Mateo? 9. You can also find information about individual fields from this menu. Right-click on the CLASS field heading and select Properties. What are the name, alias, and type of this field (fig. 3)? Field names are limited in length by the software, so they frequently end up being coded shorthand whose meaning is difficult to intuit. This issue can be avoided by creating a more accessible alias name for the field. When you create an alias field name, you are creating an alias that will be displayed in your map document. The field name will remain the same in the database, which means that the source data does not change. So as you create aliases for fields in your attribute table, you need not worry about altering the original data. 5

6 10. Open the Attribute table for Block Groups. Scroll to the far right of the table, and notice the field name RENTER_OCC. This field stores numbers for rented occupied housing in 2010, according to the US Census. 11. Right-click on RENTER_OCC and Select Properties. Change the field alias to Renter Occupied. 12. Hit OK, and notice the new field alias is displayed in the attribute table. Now close the attribute table. Figure 3 6

7 Features Have Symbology In order to make better sense of the data you have in the South San Francisco map, it will help to symbolize the layers differently. Your aim, for the purposes of this tutorial, is to create a symbology that is easy to interpret. We will investigate some of the ways ArcMap allows us to symbolize and display data. 13. Turn on the Major Roads layer if it is not on already. The roads are symbolized as thick black lines on the map. These roads are an important layer for your analysis, so you want them to be clear and visible; however, the current symbol is too dark. 14. Click on the black line below the Major Roads layer in the table of contents. This will open up the Symbol Selector where you can choose a different symbol for the streets layer (fig. 4). Figure 4 Notice that you can select from a set of predefined symbology types. You can also do a search on a specific type such roads or streets. The roads are currently displayed using the Major Road symbol. 7

8 15. You don t see a predefined symbol that works for your current purposes, so you will set your own symbology. In Color: click on and choose Gray 60% (hover your mouse over the colors to see their names). Hit OK. ArcMap allows you to change the background color of data frames. The data frame currently has a light blue background to represent the ocean. You are wondering if a darker blue would look better. 16. Right-click on the South San Francisco data frame in the TOC and select Properties. Figure 5 8

9 17. Under the General tab, you can view general data about the data frame. This is also where you can change the name of the data frame. Change the name to South SF and hit apply (fig. 5). 18. Next click the Frame tab. Under Background, there are two places you can change the background color. One option is to use the Color Selector.The other is to select a common background color from the drop-down menu (fig. 6). Figure Select a different blue and hit apply. Reset the background color to Light Blue, or find another color. 9

10 You may run into issue of wanting to see multiple layers at a time despite their covering each another in the map document. One way to solve this problem is to alter the transparency of a layer. Add the San_Mateo_Co_Landmarks_SMC shapefile to your Table of Contents (drag it from ArcCatalog). We will change the transparency of the Landmarks layer so that the block groups, the coastline, and other data can be viewed beneath it. 20. Right-click on the Landmarks layer in the TOC. Select Properties and navigate to the Display tab. 21. Find the Transparent box under the Display tab. Enter a few different values and hit the Apply button to see how these display. A higher value, something around should do the trick (fig. 7). Hit OK to exit the Layer Properties window. Figure 7 10

11 Symbolizing Features Using Attributes Open the Block Groups attribute table (right click on the layer in the TOC and select Open Attribute Table ) and notice that each block group has some associated demographic information. You decide to create a map to visualize and compare the populations of each block group. To do this, you will change the display of the Block Group layer to symbolize population values. Close the table. 22. Open the Layer Properties window for Block Groups (right click on the layer in the TOC. And click on Properties ). Select the Symbology tab. 23. At the left of this window, ArcMap provides us with a couple symbology options. In the Show box you have the options to symbolize Features, Categories, Quantities, Charts, and Multiple Attributes. Select Quantities since you are symbolizing population values (fig. 8) and leave the option of Graduated colors. Figure 8 11

12 24. Now choose POP2010 from the Value Field drop down menu. This is where you set the field containing the quantitative data you wish to symbolize (fig. 9). Figure 9 When you symbolize quantities, such as the population of a block group, you want to see where attribute values lie in relation to one another on a continuous scale. For this reason, the values must be divided into groups to make the symbology more manageable. By default, ArcMap will classify your data into 5 classes based on clusters or natural breaks within the data. 25. In the classification box, change the number of classes to 4. You may also want to normalize your data according to another variable, like area. 26. In the Fields box, select Shape_Area from the Normalization drop-down menu. It may be useful to think of normalization as a ratio; in this very simple case, you are dividing total population by block group area which reveals population density. 12

13 You can also set the color scheme to best reflect the nature of your data. ArcMap automatically assigns each quantity range a distinct color symbol, but you can change this using the Color Ramp. 27. Take a look at your options in the Color Ramp dropdown menu. Also try right-clicking on the Color Ramp and unselect Graphic View; this provides an alternative text view of your color options (fig. 10). Select a new color scheme from the Color Ramp and hit Apply. Figure Move the Layer Properties window so you can see the symbology changes in your map. You may need to turn off some layers in order to see the block groups clearly (fig. 11). 13

14 Figure Now symbolize the block groups by the population field 65 and Over and Average Family Size. 30. When you are done, select OK to exit the Layer Properties dialog. The Block Group layer is now displayed according to the attributes you have chosen. Demo: Displaying multiple attributes in just one map 14

15 Navigating the Data Frame: Zoom, Pan, and Bookmarks Now you re going to investigate Redwood City. In order to do this you first need to zoom in closer to the city. As you work in a GIS, you will find that exploration and analysis happen at different scales. You will need to move around your map efficiently, and in different ways. 31. If the Redwood City group layer is collapsed, expand it in the TOC and make it visible. 32. On the Tools toolbar, select the Zoom In tool. Use this tool to draw a box around the Redwood City area. 33. With the Zoom In tool still active, click the center of the map and notice that the scale number decreases. You can also use the Fixed Zoom tool to zoom in closer. Zoom to an extent where you can view Redwood City bike network (around a 100:000 scale display). The map's scale changes as you zoom in. The scale is shown in the scale box above the map display area (fig. 12). The amount of change depends on how large your map display area is and how large a box you drew when you zoomed in. Figure 12 The scale is the ratio between the size of features on the map and the size of those same features on the earth. If the scale is 1:5,000, that means that one unit on the map is equal to 5,000 units in the real world or, that features in the real world are 5,000 times larger than they are on the map. 34. You can also change the scale by typing directly into the scale box. Click in the scale box and delete the current number. Type 25,000 (twenty-five thousand) and press Enter. The map display changes. Now you can see parcels on the map. The Parcels layer is set to display only when the scale is 1:26,000 or less. 35. Select the Pan tool. Use this tool to move around the map. Notice that the scale does not change. Panning is a way to see different areas of the map at the same scale. To return to a previous view, you can use a bookmark. A bookmark is like a snapshot it's an area of the map saved at a particular scale. 36. From the Bookmarks menu, choose Down Town Redwood City (Bookmarks > Down Town Redwood City). 15

16 Navigating the Data Frame: Labels, Find, Identify and Measure Now you are going to explore the landmarks of San Mateo County. Zoom into the layer extent in your data frame. 37. Open the attribute table for San Mateo Co Landmarks SMC. How many landmarks are in total? (Hint: look at the bottom of the table) 38. Notice the useful information stored here: the name of each landmark as well as the type and area. What units are represented by this area? (Hint: Look in the TOC Layer Properties > Source and scroll down in Data Source until you find the Linear Units). Click Cancel. 39. To see the names of each landmark, you will turn on their labels. Right-click San Mateo Co Landmarks SMC in the table of contents and choose Label Features (fig. 13). Figure 13 16

17 40. The names of each landmark are displayed, and now you d like to adjust the font type to improve readability. Open the Layer Properties window for Landmarks and go to the Labels tab. Check the box next to Label features in this layer. 41. Notice that the Label Field is set to NAME. You want to label the neighborhoods in this map so this is the correct field for you to use. If there was another field you wanted to use to label these features, you would select it here. 42. Let s make the labels easier to read. Go to Customize Toolbars check Labeling. Activate the Maplex extension by clicking on Labeling Use Maplex Label Engine. 43. Open the Labels tab in Landmarks. Under Text Symbol, make your labels italicized, set the size to 97, and set the font color to Gray 70%. Hit Apply and OK to exit Layer Properties. Now the labels can be read more clearly (fig. 14). Figure 14 You ve heard that Palm Park is a nice place to have a picnic on a Sunday afternoon, but you have no idea where it is located. You will use the Find tool to learn which city this park is located in. 17

18 44. Click the Find tool. The Find dialog box opens. In the Find field, type Palm Park. Click the drop-down arrow next to "In" and choose San Mateo Landmarks. Click Find. 45. Move the Find dialog box so you can see both the map and the box. In the Find dialog box, right-click Palm Park to open a context menu (fig. 15). Figure Choose Flash from this menu. The park will flash on the map (If you don t see the flash, move the Find dialog and try it again). 18

19 47. You can also choose Select in order to highlight this park on the map. With Palm Park highlighted on the map, find the city that it is located in (fig. 16). 48. Choose Zoom To from this menu. Your map display will zoom to an extent around Palm Park. 49. Create a bookmark for this location and view. You can do this one of two ways: either select Create Bookmark from this context menu, or go to View > Bookmarks > Create. Name your new bookmark Palm Park. Close the Find window. Figure 16 There are a few smaller parks in the same neighborhood, near Palm Park. You will use the Identify tool to learn the names of these parks. This tool is very useful for exploring features in your map document. 19

20 50. Select the Identify tool and the Identify window opens. Now click on a park. The park should highlight for a moment in the map display to indicate your selection (If you have trouble selecting the park, return to the Identify tool and select Landmarks from the Identify from drop-down menu. This will limit your selection to features only from this layer) (fig. 17). Figure Once the park is selected, you will see a list of information about the park, including its name, the name of the agency that manages the park, the City it is located in, information about access, and many other things. 52. Use the Search tool to pinpoint the location of Clifford School, Pulgas Ridge Open Space, and Garrett Park (all of them part of the Landmarks layer). Go to the Down Town Redwood City Bookmark. You can see on the map that the width of Redwood City Hall is just about half the width of the Library. You will use the Measure tool to find the area of City Hall and compare that to the area of the library. 53. Select the Measure tool. In the Measure window, the Measure Area button should be selected (depressed). Next, you'll set the area units to Acres. To the right of the Measure Line button, click the Choose Units down arrow, point to Distance, and select Acres (fig. 18). Figure 18 20

21 54. In the map, click once at the west end of City Hall. Double-click to finish tracing the area. The area you measured displays in the Measure window (fig. 19). Figure Now measure the area of the library. First click once in one corner, follow the vertices that define the shape of the library and double click in the corner where you started. 56. What is the approximate area of city hall? Is the library exactly dobule, less than or more than half the area of city hall? Save and Exit Before you close ArcMap, you will save the updated version your version of SouthSF.mxd. You have changed feature symbology using both the symbol selector and quantities. You have also selected features like Palm Park and created a new bookmark. 57. Go to File > Save As. 58. In the Save As window, navigate to your personal folder. 59. Give your map document a meaningful name; perhaps SouthSF_MyName.mxd or something else that will allow you to easily recognize your map. 60. Hit Save. Quiz time!! 21