When a layer contains a large number of point features, showing each feature individually on the map is often not useful. In this scenario, point features often overlap, making it difficult to distinguish between features. Even when they do not overlap, it is usually difficult or impossible to visually extract meaningful information when hundreds or thousands of points are shown all at once.
One approach to resolving this issue is to create a heat map. A heat map represents the geographic density of point features on a map by using colored areas to represent those points. The areas will be largest where the most points are concentrated.
Heat map layers and layers that are clustered cannot be shared to ArcGIS as a layer, but they can be shared as part of a map. In the map viewer on ArcGIS.com, the heat map layer displays as a point layer instead of rendering as a heat map.
- Click the Contents tab to display the Contents pane.
- On the Contents pane, click the settings icon to the right of the point layer for which you want to configure a heat map.
- Click Heat map.
The Heat map item will be disabled if Clustering is turned on. You must first turn off clustering before applying and configuring a heat map.
- Click the On/Off selector under the layer to turn on the heat map for the layer.
To turn off clustering, click the On/Off selector again.
- Click Heat map.
- To change the way the heat map appears on the map, from the Contents pane, click the arrow to the right of the heat map layer and click Configure heat map.
- To change the way the heat map appears on the map, do any of the following to configure it:
- Choose a color scheme from the Color scheme menu.
- Adjust the intensity of the heat map using the Radius slider or by typing a number between 10 and 100 in the text box beside the radius slider.
- Click OK when you are finished.
A new heat map layer appears in the Contents pane. The map automatically displays the heat map under the original points layer.