In geography, local relief is the topographic variation of a specific area. Since few areas have a consistent elevation in their topography, a relief map can be used to represent the increases and decreases in elevation.
Relief maps typically differentiate between elevations using either three-dimensional, colored or shaded imaging. Local relief maps are useful for geographers because they provide a scaled image of an area. These scaled images help create an overall understanding of a region that is too large for the naked eye to accurate evaluate. Local relief maps also help geologists over time because water erosion as well as increases and decreases in elevation can be tracked by creating new maps at regular intervals. Establishing how the topography of a region may impact the climate and determining the suitability of an area for farming are other reasons why local relief maps are helpful.
When using relief maps to track geological patterns in elevation, however, it is essential for the area being mapped to remain consistent. Since the scale of a relief map is relevant to the highest and lowest points of a specifically designated region, increasing or decreasing the parameters of the region being measured can significantly change the scale by including topographical areas that vary significantly in elevation.