Slope is a key factor influencing the configuration of Earth’s relief. Its analysis is essential in disciplines such as geomorphology, hydrology, cartography, and land planning.
Slope refers to the inclination of the Earth’s surface between two points at different elevations. It is mathematically defined as the ratio between the elevation difference and the horizontal distance between the two points (Hernández, 1998).
This measurement can be expressed either in degrees or percentage. In ArcGIS Pro, slope maps can be generated using a Digital Elevation Model (DEM) through tools like “Slope” or “Surface Parameters”.
Accessing the Slope Tool
To begin, the DEM file (for instance, “DEM.tif”) should be added using the path: Map > Add Data > Data. Then, the slope analysis is performed using the “Slope” tool, found at:
Geoprocessing > Toolboxes > Spatial Analyst Tools > Surface > Slope
Configuring the Slope Tool
The “Slope” tool calculates the slope from the input DEM. The required parameters are:
- Input raster: Select the DEM layer to be analyzed.
- Raster output: Define the path where the resulting slope raster will be saved.
- Output measurement: Choose between “Degree” for decimal degree output or “Percent rise” for slope in percentage.
- Z factor: Optionally, enter a value to match the vertical (Z) units to the horizontal (XY) units, especially if they differ.
- Target device for analysis: Select whether to perform the computation using the GPU, CPU, or both.
Configuration parameters of the “Slope” tool.
Output and Interpretation
The tool generates a slope raster where terrain inclinations are represented using a color gradient. Areas with lower slopes typically appear in lighter colors (e.g., green), while steeper regions are shown in darker colors (e.g., red).
This type of output is fundamental for topographic analysis, allowing users to visualize and evaluate slope variations across a landscape for diverse applications.
Slope raster in degrees.
