Hurricane Emergency Management with ArcGIS Online

Hurricanes can result in tremendous damage and loss of life. With online maps, you can help plan evacuation strategies and share your findings with the people who make decisions. You'll create a map of Charleston, South Carolina, based on publicly shared data. By analyzing vehicle ownership across the city, you'll pinpoint areas that may have difficulty evacuating in time. Then, you'll present your results as a professional-looking web app for others to explore.

Goal

In this lesson, you'll create a map that shows hurricane evacuation routes in Charleston, SC. First, you'll create a map and locate Charleston, SC. Then, you'll add a map layer that shows evacuation routes. Lastly, you'll change the way your map and layers look to better display the data.

What is ArcGIS Online?

ArcGIS Online is a web-based GIS platform that allows for collaborative creation and sharing of GIS data, maps, and web mapping applications. Many geospatial analytical capabilities of GIS are integrated in ArcGIS Online, with the difference that the only software needed is a web browser (and Internet connection!).

In this lecture, we will learn how to navigate arcgis.com, create and share exciting mash-up maps and use your crowd-sourcing efforts with out-of-the-box templates.

Logging into ArcGIS Online

Students, faculty, and staff at Clemson University can create their own ArcGIS Online account under our Clemson University Organization by following the instructions below.

- Go to arcgis.com and click Sign in. You will see the window on the picture below (#1) Click on Your ArcGIS organization's URL.

- Under the box your ArcGIS organization's URL. Enter clemson as shown below and click Continue (#2).

- In the window that appears, select Clemson University (#3). Use your Clemson username and password to log in (#4).

- If you see the window below that means you have successfully logged into your ArcGIS Online account.​

• • • • • Tip:

        • If you're in a new session, clicking Map will open a new map. Otherwise, it will open an existing map (the last map you were using). If an existing map opens, click New Map.

• • • • Your map's appearance varies based on your account and your browser window size The only layer on the map is the basemap, which provides geographic context such as water bodies and political boundaries. The default basemap is Topographic. See the picture below:

• • • • On either side of the map are the toolbars. The Contents (dark) toolbar allows you to manage and view the map contents and work with the map. The Settings (light) toolbar allows you to access tools and options for configuring and interacting with map layers and other map components. The Layers pane is also open. As you add data to your map, it will be listed here. Next, you'll navigate to your area of interest.

Navigation in a map in ArcGIS Online

Add a layer

Next, you'll add a layer to your map that shows hurricane evacuation routes in Charleston. You'll add this layer from ArcGIS Living Atlas of the World, a collection of curated geographic data from around the globe.

• • On the Contents (dark) toolbar, click Layers.

• • In the Layers pane, click Add layer.

• • • • The search pane appears.

• • Click My Content and select Living Atlas.

• • • The layer is added to the map and the Properties pane opens.

• • • The routes are displayed as red lines that travel throughout the city. The line thickness and color show the different types of roads. The dark red lines show major interstates while the lighter red lines show state highways. While these lines are visible, you'll change the basemap to one with a lighter color scheme so the routes stand out better.

• • On the Contents (dark) toolbar, click the Basemap button.

    • • The Basemap pane appears. It lists basemaps that you can choose to add to your map.

  • In the Basemap pane, find and choose Light Gray Canvas.

• • The basemap updates. The evacuation routes stand out much more against the lighter-colored, less-detailed basemap.

Add Bookmarks

Before you continue, it's a good idea to explore the map and familiarize yourself with Charleston's geography. With a better understanding of the area, you'll be better informed to make decisions and draw conclusions later on. Before you explore, you'll create a bookmark of the current extent so you can quickly return to it when needed.

• • On the Contents toolbar, click Bookmarks and choose Add Bookmark.

• • • • A text box for the bookmark's title appears.

• • For Title, type Charleston and click Add.

• • • • The bookmark is added. You can choose this bookmark to automatically navigate to the map extent where the bookmark was created.

• • Close the Bookmarks pane.

    • • You're now ready to explore the city.

      • Charleston has several major bayous (flat, low-lying marshes or wetlands) that run through the city. During a hurricane, these bayous are prone to flooding and can become especially dangerous. You may want to keep this area in mind when you later identify high-risk areas.

  • Zoom in to the Charleston Harbor area, near the Charleston label, until the Mt Pleasant and North Charleston appear on the map.

• • • • • Tip:

        • There are several ways to zoom. You can click the Zoom In button in the corner of the map or scroll up with the mouse wheel. Alternatively, you can press Shift while drawing a box around the area you want to zoom to.

• • In the Bookmarks pane and choose Charleston.

    • The map zooms to its original extent.

Change the style

Although the evacuation routes stand out more against the light basemap, they could be even more eye-catching. You'll change the layer's style, also known as its symbology, to give the routes a brighter color and a thicker line width.

• • In the Layers pane, make sure the Hurricane Evacuation Routes layer is selected.

  • On the Settings (dark) toolbar, click Styles.

• • • • The Styles pane appears. Layers can have either a single symbol or multiple symbols based on attribute information such as names or speed limits. You'll learn more about attribute information later. Currently, the roads are being drawn based on their classification, but you're only interested in showing the location of roads, so you'll symbolize the layer with a single symbol.

• • For Try a drawing style, click Location (single symbol).

• • • • The Road Classification attribute and Types (unique symbols) options are removed.

• • For Location (Single symbol), click Style options.

• • • • The Style options pane opens. You'll change the color and size of the symbol itself.

• • For Symbol style, click the line symbol.

• • • • A window appears with a color palette and other options. None of these color options are exactly what you want, so you'll select a custom color by entering a six-character hexadecimal code.

• • On the color palette, expand Custom color. For Hex, type or paste 004C73 and press Enter.

• • • • After you choose the color, the custom color changes to a shade of dark blue. Now, you'll make the line thicker to stand out better on the map.

• • Expand Stroke and change Width to 3 px.

• • • • The map updates with the new line color and width settings.

      • With the thicker, brighter symbol, the routes are eye-catching and stand out.

      • The routes layer is a feature layer, which means it consists of individual features with distinct characteristics. In this case, each route segment is a feature. You can view a feature's characteristics, also known as its attribute information, by clicking the feature on the map and opening its pop-up.

• • Close the Line window. In the Style options pane, click Done, and in the Styles pane, click Done.

  • Click a segment of an evacuation route.

    • • Its pop-up appears.

• • • • From the pop-up, you learn the name of the route, as well as whether the route is paved and what type of road it is. The owner of the Hurricane Evacuation Routes layer specifically configured this pop-up to present attribute information in a clear and readable way. You'll learn how to configure pop-ups in a later lesson.

• • Click a few more route segments to view their pop-ups. When finished, close the pop-up.

Add demographic data

Next, you'll determine areas of the city that are likely in need of evacuation assistance. To do so, you'll add a layer containing demographic data by census tract. United States census tracts divide counties into smaller geographic areas, which are useful for revealing spatial patterns.

• • In the Layers pane click Add Layer.

    • • At the top of the pane, click My Content and choose Living Atlas.

  • In the search box, clear any existing search text and type ACS Vehicle Availability Variables. Press Enter.

  • Add the ACS Vehicle Availability Variables layer.

• • • • The layer is added to the map. It's symbolized based on Percent of households with no vehicle available

• • The layers are reordered and the evacuation routes layer is now visible on top of the census tracts on the map.

• • • Next, you'll look at the layer's attributes. Every layer has a table that contains all attribute data about the geographic features in the layer. You'll view the table for the ACS Vehicle Availability Variables layer to find data that will help you identify areas that are vulnerable during a hurricane.

• • In the Layers pane, for the ACS Vehicle Availability Variables layer, click Open actions and choose Show Table.

• • • The layer's attribute table appears. Each row in the table represents a feature (in this case, a census tract area). The columns, or fields, provide different types of information about the census tract features. For example, the ID field contains a code that represents the state, county, and census tract identifier for each census tract feature, and the Total Households (ACS 2015-2019) field shows the total number of households in each tract.

• • If necessary, use the scroll bar at the bottom of the table to scroll all the way to the right.

  • Locate the Percent of Households without a Vehicle field.

• • • • • Tip:

        • To see the full attribute name, resize the column width or point to the header.

• • • • This field shows the percentage of households in each tract that do not own a vehicle. Areas with a high percentage of people who don't own vehicles might need help evacuating.

• • Close the table.

    • In this map, census tracts with a higher-than-average percentage of households without a vehicle stand out in blue. Based on the legend, the average percentage is about 6 percent. A clear pattern of limited access to vehicles stands out in downtown Charleston, close to the harbor. These census tracts would likely benefit the most from increased evacuation assistance, such as public transportation.

  • Now let's give the layer a more descriptive name.

  • In the Layers pane, for the ACS Vehicle Availability Variables layer, click Open actions and choose Rename.

• • In the Rename window, type Percentage of Households Without a Vehicle and click OK.

    • • The layer name updates in the Layers pane.

Save and share the map

• • Next, you'll save your evacuation map and assign it a title, tags, and a summary to make it easy to find and identify later. Then, you'll share the map to make it accessible.

  • On the Contents (dark) toolbar, click the Save and open button and then click on Save.

• • • • The Save Map window appears.

• • For Title, type Charleston Area Evacuation Map and add your initials to make the title unique.

    • • Next, you'll add tags. Tags are terms that allow users to search for your map on ArcGIS Online.

  • For Tags, type each of the following tags, pressing Enter after each one:

    • • Hurricanes

      • Roads

      • Evacuation Routes

      • Charleston

      • Finally, you'll add a summary. The summary appears on your map's details page and should provide information about the map so users better understand your map's purpose.

  • For Summary, type This map shows hurricane evacuation routes in Charleston, South Carolina.

  • Click Save map.

• • • The map saves. It now appears in your account's content. You can access your content by clicking the options button next to the map's name and choosing Content. For now, you'll set the sharing permissions.

• • On the Content toolbar, click the Share map button.

• • In the Share window, select Everyone (public) and click Save.

Create a web app

You finished your web map by adding and styling demographic data to show census tracts with a high percentage of households without vehicles. Next, you'll use your map to create a web app. A web app is a customized user interface that enhances your map's appearance, adds (or removes) functionality, and helps you integrate the map with other media. You can choose from a variety of configurable templates, depending on how you want to display your map. You simply want to showcase your map to the public, so you'll configure a Basic Viewer app template with only a few standard navigation tools.

• • On the Contents (dark) toolbar, click the Create app button and choose Instant Apps.

• • • • The Instant Apps gallery appears. You want your map to be the primary focus of your app. You also want to show the legend, pop-up information, and a map description. For these purposes, you'll use the Minimalist app.

• • On the Minimalist card, click Choose.

• • • • The Create App - Minimalist window appears. Before you configure the app, you must specify its title, tags, and summary. By default, the app has the same information as the web map used to create it. You'll change the title to better represent what you intend the map to emphasize and leave the other parameters unchanged.

• • Change Title to At-Risk Population in Charleston. For Tags, type each of the following tags, pressing Enter after each one:

    • • Hurricanes

      • Roads

      • Evacuation Routes

      • Charleston

• Click Create App.

The app opens in its configurable state. In the Welcome to the app setup page, read the text and click Next. Same with Check out the new position manager. At Find tools using the settings search, click Got it. The app opens in its configurable state.

Configure the app

Next, you'll change elements of the app's presentation to better communicate the map's story to users. There are four tabs of configurable parameters available for Express Setup. Since you've already selected the Charleston map, you'll skip to the second step.

• • In the Express Setup pane, click Step 2. About.

• • • • The About pane opens. In this pane, you can change the name of the application, which by default is the same as the map.

• • For App title, type or paste At-Risk Population in Charleston.

    • • In this pane, you can also control which widgets appear when it is first launched.

  • For Select which panel to open at start, confirm Legend Panel is selected. For Legend panel and Pop-up panel toggle the buttons on and toggle the other options off.

• • • • Setting Legend Panel as the default panel will ensure that people viewing your app know what data they're looking for on the map.

• • Click Next.

    • • The Interactivity pane appears. On this pane, you can set different user navigation features, like search. You'll turn off Search, though, since app users are already at your area of interest.

  • In the Interactivity pane, turn off Search.

• • Click Next.

    • • The pane updates to the Theme & Layout pane.

      • The final step of app configuration is choosing the theme and layout. In this pane, you can select different color options and places where you want the widgets to show. By default, the theme of the application is Light, which matches your basemap.

  • In the preview, test your app's functionality. Navigate the map and click the various buttons in the user interface.

• • • When you're happy with your app configuration, you'll publish it so that you can share it.

• • At the bottom of the Express Setup pane, click Publish, then click Confirm.

    • • A success window confirms that the app is published. Your app is not public yet, so it is replaced by the Share window.

• • In the Share window, for The app is not share with the public, click Change Share Settings.

    • • The app's details page opens. This page provides information about your content. First you'll share the app, then you'll edit the metadata to help people using the app understand what they're looking at and how to use it.

  • On the item page, click Share.

• • • • The Share window opens. There are multiple ways to share content to different groups of viewers. For example, if you choose to share to your organization, only people with accounts in that same organization will be able to access your content. You want this app to be available to everyone, so you'll share it publicly.

• • In the Share window, for Set sharing level, choose Everyone (public) and click Save.

• • • • Now the app is configured and shared. As a final step, you'll add information about the app to the item details page.

Edit the item details

• • Next, you'll edit its details to provide meaningful information about the map and data for the users. This information is called metadata, and it's important for all maps and apps to have it. The Item Information bar indicates your progress toward high-quality item information and indicates the most important improvement you can make.

  • Under your Contents in ArcGIS Online, find the web app you just created. Under Item Information, click Add a summary.

• • • • The Edit Summary box activates.

• • Type (or copy and paste) the following text, then click Save:

    • • This web app highlights areas in need of assistance during a hurricane evacuation in Charleston, SC.

• • • • The thumbnail image is currently a default app icon. Next, you'll change this.

• • Click Edit thumbnail. In the Create Thumbnail window, click Create thumbnail from map.

• • In the Create Thumbnail Using Map window, search for Charleston, SC. Once the map centers on Charleston, click OK.

    • • A map of Charleston is added as the thumbnail.

  • Click Add a description.

    • • The Edit Description box actives. A description should be even more detailed and in-depth than a summary. It should explain not only the app's purpose and what kind of data it shows, but also information about how to use the app and how it was created.

  • Type (or copy and paste) the following text:

    • • This app shows evacuation routes and demographic data by census tract for Charleston, SC. The darker blue tracts have a higher percentage of households without a vehicle. This pattern helps answer the question: Where in Charleston should we provide evacuation assistance during a hurricane?

      • Use the Layers and Legend tools to learn more about the data shown in the map. Click individual census tracts to see pop-up information, including the percentage of households without a vehicle.

      • The map in this app contains a Living Atlas layer of Charleston evacuation routes and a layer of Charleston demographic data. The demographic layer is styled using an Arcade expression that calculates the percentage of households without a vehicle. This information is also provided in pop-ups.

  • Click Save.

    • • The Item Information progress bar indicates that you are closer to completing the item information for the app.

  • Next to Item Information, click Learn more.

    • • A complete list of suggested improvements is displayed. You have completed all but one: Add terms of use.

  • Click Add terms of use.

    • • The Edit Terms of Use box becomes active. Your data comes from local and federal governmental authorities and is public domain, so there are no terms of use.

  • Type None. Public domain data. Click Save.

    • • The details page is complete. You can copy the app's URL to share it with anyone.

In this lesson, you created a map with a layer of hurricane evacuation routes in Charleston, SC. You added demographic data by census tract and used smart mapping to emphasize areas with limited vehicle ownership. The spatial patterns revealed in your map helped you determine where evacuation assistance is most needed in the event of a hurricane. Finally, you shared your findings by turning your map into an interactive web app.