Raster Overlay is used for which data type?

• A. Continuous data such as heat maps and pollution.
• B. Discrete data such as points, lines, and polygons.
• C. Temporal data changes.
• D. Qualitative zoning maps.

Answer: (A)

Raster overlay combines values from multiple raster layers on a cell-by-cell basis, so it works most naturally when the data are numeric and continuous. Each cell has a value you can add, multiply, compare, or weight to produce a new surface. That makes it ideal for things like heat maps and pollution concentrations, where you want to blend or analyze how those continuous surfaces interact across the landscape (for example, estimating overall exposure by weighting pollution and population surfaces).

Discrete data such as points, lines, and polygons are usually handled with vector overlay techniques (intersections, unions, or dissolves) or by converting to raster first, which isn’t the typical use case for raster overlay itself. Temporal data changes can be analyzed over time with raster time series, but overlay is fundamentally about combining layers at a single moment, so time adds an extra dimension rather than changing the primary data type being overlaid. Qualitative zoning maps are often categorical and better suited to vector approaches unless reclassified into numeric rasters, which then becomes a different kind of analysis.

So the best fit for raster overlay is continuous data like heat maps and pollution.