Have you ever seen a map? If you have, then you’ve seen an example of a geospatial visualization. These kinds of diagrams showcase data in relation to its physical location.
Many resources classify geospatial visualizations as a subgroup of charts. This glossary considers them separate. This makes it easier to explore and discover new ways of performing visual analytics. We do not intend to create a new taxonomy through this approach. Check out the examples below and the information on what makes geospatial visualizations so important to analyzing data to learn more.
What is a Geospatial Visualization?
These visualizations focus on the relationship between data and its physical location to create insight. Any positional data works for spatial analysis. What makes geospatial visualizations unique is the scale. A diagram of circuits on a microchip explores position, but it is not geospatial. It does not map to Earth or another planetary body. A map of the stars is also not considered geospatial, but a map of the surface of Mars is. Geovisualization overlays variables on a map using latitude and longitude to foster insight.
Maps are the primary focus of geospatial visualizations. They range from depicting a street, town, or park or subdivisions to showing the boundaries of a country, continent, or the whole planet. They act as a container for extra data. This allows you to create context using shapes and color to change the visual focus. They help identify problems, track change, understand trends, and perform forecasting related to specific places and times.
Geospatial visualizations highlight the physical connection between data points. This makes them susceptible to a few common pitfalls that may introduce error:
- Scaling - Changes in the size of the map can affect how the viewer interprets the data
- Auto-correlation - A view may create an association between data points appearing close on a map, even for unrelated data
Geospatial visualizations can tell stories about human existence. Historically, doctors and scientists have used this kind of presentation to map illness, resources, and even simple navigation. Charles Minnard, a French civil engineer, created a geospatial visualization that told the story of dictator Napoleon Bonaparte’s defeat at Waterloo, including several different details like temperature, environment, and army size. In recent years, the most prevalent use of geospatial visualizations is likely through Google Maps and similar apps. They allow us to find the fastest way to travel from point A to point B or to identify where something is on Earth.
Key Types of Geospatial Visualizations
The table below contains a brief description for the most common types of geospatial visualizations. As the Reference Library expands in depth and breadth more types will be added and each will have a page dedicated to showing practical examples and explaining when to use them.
Proportional Symbol Maps
Symbols placed at locations represent events of interest. Measures are represented by shapes using size and color to display values.
Choropleth, Isopleth, Area Maps
These area maps represent values by different shades of color over a geographic region. Choropleths rely on boundaries, while isopleths rely on density to display the data.