In the previous lesson, you calculated malaria incidence rates. In this lesson, you'll share your results as a web map on ArcGIS Online or your ArcGIS Enterprise portal.
Share the map
One of the most important things to do before sharing data or maps is to ensure the metadata for the item has been completed. You know from previous lessons that the malaria incidence data has been obtained from the Malaria Atlas Project and that population estimates have been provided through the Living Atlas. You'll add both data providers in the metadata before styling the map.
To prepare the map for styling you'll first change the basemap. The default basemap is World Topographic + World Hillshade. These basemaps serve as good references when it is important to understand the landscape's relationship to your data, but that is not required for this use case. You'll change the basemap to Dark Gray Canvas to help your symbology stand out.
- On the ribbon, click the Map tab. In the Layer group, click Basemap and choose Dark Gray Canvas.
The World Topographic and World Hillshade layers are removed from the Contents pane and are replaced with the Dark Gray Canvas layer.
- In the Contents pane, remove all layers and tables except DRC_Admin, Sources, World Dark Gray Reference, and World Dark Gray Canvas Base.
- Move the Sources layer to the top of the Contents pane.
- In the Contents pane, right-click Map and choose Properties.
- In the Map Properties window, choose the Metadata tab.
The information on the Metadata tab will be carried over to your exported web map. ArcGIS Pro will not allow you to export the map without filling in the metadata.
- For Title, type Democratic Republic of the Congo Malaria Incidence 2000 – 2015 – <your initials>.
Each item shared requires a unique name. As a user in an organization, you should attach your initials to any items you create.
- For Tags, type Democratic Republic of the Congo, Congo DRC, Malaria, SDG, SDG#3.
- For Summary, type This map displays malaria rates from 2000-2015 for the Democratic Republic of the Congo.
- For Description, type This map displays the malaria incidence rate per 1,000 population for 2000, 2005, 2010, and 2015 in the Democratic Republic of the Congo. The incidence rate is calculated for reporting on the United Nations Sustainable Development goal #3 Good Health and Well-Being on indicator 3.3.3 End Epidemics of Malaria.
- For Credits, type The Malaria Atlas Project, ArcGIS Living Atlas.
- For Use limitations, type None.
- Click OK.
Next, you'll share your map as a web map.
- On the Share tab, in the Share As group, click Web Map.
- In the Share As a Web Map window, for Name, type Congo DRC Malaria Incidence 2000 – 2015 – <your initials>.
- For Select a Configuration, choose Editable under Copy all data.
- For Share with, check Everyone.
- Click Share.
The map is now accessible through your ArcGIS Online or ArcGIS Enterprise account. When ArcGIS Pro has finished publishing the map, you'll see a confirmation message that includes a link to manage your web map.
- At the bottom of the Share As Web Map pane, click Manage the web map to open your map.
- Save and close ArcGIS Pro.
Employ smart mapping
One way to visualize the malaria incident rate per 1,000 people for each year is to create a choropleth map. This type of map assigns a gradient color scheme to the data, and each area would be shaded according to the incident rate. However, this type of symbology can be misleading, because it leads you to associate the size of an area with the number being reported. Administrative regions with cities, which have small geographic regions but dense populations, would be visually misrepresented.
The appropriate way to communicate this data is to use proportional symbols. Proportional symbols show relative differences among features. Next, you'll calculate the malaria incidence rate per 1,000 population, use proportional symbols to represent malaria rates, and show changing rates over time. You'll use Esri's smart mapping functionality, which automatically analyzes your data and offers data-driven styling suggestions, to visualize the data.
- In the Congo DRC Malaria Incidence 2000 - 2015 item details page, on the right side of the page, click Open in Map Viewer.
- Above the map pane, click Sign In and sign in to your account.
- In the Contents pane, turn off the Sources layer.
Next, you'll symbolize the AdminBorder layer.
- Under the DRC Admin layer, click the Change Style button.
The Change Style pane appears. There are options to change the display attribute and edit the symbology style. There are options to change the display attribute and edit the symbology style using any of the attributes found in the data. This dataset contains the rate in 2000 and the rate in 2015, but it does not contain the change between the two years. You'll first create a custom attribute expression using Arcade to show the change in trends from 2000 to 2015. Then you'll configure the pop-ups to include a bar chart showing the rise and decline of incidence for each year.
Arcade is an expression language created by Esri that is compatible across the ArcGIS platform. The language provides a simple scripting syntax that allows users to control how features are rendered, control label text, and more. You can read more about the Arcade language on the ArcGIS for Developers website.
- In the Change Style pane, for Choose an attribute to show, choose New Expression.
The Script Editor appears. In the editor, you can create custom attributes by combining globals, which are attributes in the data, and basic scripting functions, which are statements that will perform a task or calculate a value. You'll copy a preconstructed expression into the editor.
- Delete the text in the Script Editor and copy the following expression: var y2000 = $feature.Incidence2000 var y2015 = $feature.Incidence2015 when(y2015 > y2000, "Increase", y2015 < y2000, "Decrease", "No Change")
Alternatively, you could construct the expression by selecting the same code from the Globals and Functions tabs.
The expression measures if there was an increase or decrease from 2000 to 2015. The first two lines create variables for each year and assign them to the corresponding feature attribute. Then, a function is written that compares the years and assigns the comparison outputs one of three labels: Increase, Decrease, or No Change. The expression below reads: "When incidence rates in 2015 were greater than 2000, return 'Increase', when incidence rates in 2015 were less then 2000, return 'Decrease', all other results will return 'No Change'.
Now you'll name the custom expression.
- At the top of the Script Editor, click Edit.
- In the text box, type Incidence Change.
The expression title will be shown in the legend.
- Click Save.
- Click OK.
The map symbology changes to show to the custom attribute expression you just coded, which automatically symbolizes the data using the Types (Unique symbols) style.
The change in incidence rate is symbolized as a choropleth map that displays either decreasing (red) or increasing (blue) from 2000 to 2015. Color is useful to show the direction of change, but you can do more by showing the amount of change using proportional symbols.
- In the Change Style pane, for Choose an attribute to show, click Add attribute.
By adding a second attribute you can display two variables in your map using different cartographic techniques.
- For the second attribute, choose New Expression.
The Script Editor saves all expressions you create. Since you want to visualize the same variables, you'll edit the expression you previously created.
- In the Script Editor window, click the Existing tab.
The Existing tab lists all Arcade expressions you have built for the current web map. You can see the Arcade expression you built for the first attribute.
- Click Incidence Change (Color Style) to select the Arcade expression.
- Rename the expression to Incidence Change (Rate per 100,000 people).
- In the Script Editor replace when(y2015 > y2000, "Increase", y2015 < y2000, "Decrease", "No Change") with abs(y2015-y2000).
- Click OK.
The map symbology changes to show size as a secondary visual variable that represents the amount of change. This is useful to distinguish between regions such as Bandundu which experienced a large decrease in malaria incidence, and Katanga which experienced a small decrease. You can also see that the two regions with increased rates, Maniema and Kinshasa, only experienced small increases.
- In the Change Style pane, under Select a drawing style, for Types and Size, click Options.
- In the next pane, for Types (Unique symbols), choose Options.
In the Change Style pane, you will edit the color scheme to better highlight change in the regions.
- Next to Decrease, click Change symbol.
- In the Editing window, choose the Fill tab, and select a mid-range blue color (#00C5FF). Click OK.
- Change the Increase symbol fill color to a mid-range orange color (#FFAA00).
The circles on the map have changed colors to show areas with a decrease in malaria incidence in blue and areas with an increase in orange.
- Click OK and click Done twice to close the Change Style pane.
Now that your map is styled, you'll configure pop-ups for the layer to display a chart graph that shows incidence for every year. The map displays long-term trends from 2000 - 2015, but the chart graph will allow insight into rates for years in-between.
- In the Contents pane, under the DRC Admin layer, click More Options, and choose Configure Pop-up.
The Configure Pop-up pane appears. Here you can edit the title of the pop-up, choose which attributes to display, write custom Arcade expressions, or add media. The pop-up title is already set to the NAME attribute.
- For Pop-up Contents, change Display to No attribute information.
- In the Configure Pop-up pane, under Pop-up Media, click ADD and choose Column Chart.
- In the Configure Column Chart window, replace any text in the Title text box with Malaria Incidence Rate 2000-2015.
- Under Chart Fields, ensure only the following fields are checked: IncidenceRate2000, Incidence Rate2005, IncidenceRate2010, and IncidenceRate2015.
- Click OK to close the window and click OK again to close the Configure Pop-up pane.
- Click any administrative region on the map to test your pop-up configuration.
The new pop-up window displays the name of the administrative region and four columns for each incidence year. If you hover your pointer over a column, a tooltip appears displaying the specific incidence rate. Also notice the right-pointing arrow in the upper right of the pop-up window. This indicates that the point where you clicked has more than one pop-up, as may be the case when you are displaying multiple overlapping layers. In this map, the Sources layer also has a pop-up for the entire country.
- Click Next feature to view the Sources pop-up.
Now that your web map is complete, you'll save and share it.
- Above the Map pane, click Save and choose Save.
- Above the Map pane, click Share.
The Share window allows you to control who you map will be shared with and provides a link to the web map. Additionally, you can choose to embed the map into your website with various configurations for map element settings.
- Copy the url under Link to this map and paste it in a new tab to view your map.
In these lessons, you calculated malaria incidence rates; created maps to visualize incidence trends over time; and edited, updated, and exported a spreadsheet containing the calculated rates. By creating these maps and spreadsheets, you can visually communicate whether trends are increasing or decreasing and understand where aid and resources are needed most. While the maps are a visual communication tool, you can also share your calculated analysis through the spreadsheet.
You have now learned to how to use spatial analysis and data to calculate the Sustainable Development Goal (SDG) indicator 3.3.3 malaria incidence per 1,000 population. The workflow you used here can be used in future SDG 3.3.3 reporting and can be adapted to include updated data as well. Finally, the maps you created can be shared to gain valuable insight into incidence trends throughout the country.
You can find more lessons in the Learn ArcGIS Lesson Gallery.