Geovisualization Developer's Guide

Heat Maps

A heat map is a two-dimensional representation of geographically-related data that applies color to the map according to interpreted values. Heat maps are powerful visual aides that can immediately imply differences or activity across geographical areas. They are especially suited for presentations to show an indicative trend at a high level. Patterns can be identified quickly and relevance determined for even the largest datasets.

Figure 1. Heat map with and without alpha mask by density

Typical use cases for heat maps are large datasets containing geographical coordinates (latitude and longitude) and thousands or millions of records that are best represented as a distribution of data on a map. For example, heat maps can be used to represent data as varied as:

  • weather patterns over time for a specific region
  • language usage across countries
  • mobile network usage in cities

Geovisualization allows you to create powerful heat maps with a fine degree of control over the data representation; see Heat Maps for details.

The following are examples of heat maps created with Geovisualization. Click the images to view the full code for these examples.

Figure 2. A heat map showing distribution of mobile network signal strengths (click the image to go to the code example)
Figure 3. A heat map using client-side data filtering (click the image to go to the code example)