What defines a continuous raster?

A continuous raster is defined by data that reflects a continuous surface, which is the underpinning characteristic of this type of raster dataset. Continuous rasters represent phenomena that can take on an infinite number of values across a surface, such as elevation, temperature, or precipitation. These values vary smoothly from one location to another, which distinguishes continuous rasters from discrete rasters that categorize data into distinct classes or types.

For instance, in a digital elevation model (DEM), the elevation values change gradually across the landscape, creating a smooth and continuous representation of terrain. This is different from classified categories, which group data into specific classes and do not reflect variations across a surface. Similarly, composite layers combine different datasets but do not inherently describe continuity in the values they represent. Specific land uses pertain to the classification of areas based on human activities or types of cover and do not embody the continuous nature of surface data. Therefore, the defining feature of a continuous raster lies in its ability to depict a gradual change in value over space.