What is the minimum bit depth commonly required for an elevation raster?

The minimum bit depth commonly required for an elevation raster is 16 bits. This is because elevation data often needs to represent a wide range of values to accurately capture the variations in terrain. A 16-bit raster allows for 65,536 different values, which is essential for differentiating among the nuanced elevations found in larger geographic areas.

With 16 bits, it becomes possible to express detailed elevation information that can accommodate varying topographies, such as mountains, valleys, and plateaus. Using a bit depth of 8 bits, on the other hand, would allow for only 256 values, which is generally insufficient for representing the elevations effectively in most GIS applications. As a result, this limitation could lead to a loss of important detail in the elevation data, impeding analyses and decision-making that depend on precise topographic information.

Although 12 bits could theoretically provide a better depth than 8 bits (allowing for 4,096 values), it still falls short compared to 16 bits when it comes to capturing the complexity of elevation data required for most GIS projects. Therefore, 16 bits is the standard minimum bit depth in this context.