Surface Analysis
Definition
Surface analysis in Geographic Information Systems (GIS) refers to the process of interpreting and understanding the topographical features of a terrain represented in a digital format. It includes the examination and analysis of elevation data to discern physical characteristics of the Earth's surface, such as hills, valleys, slopes, and aspects. This analysis is fundamental in a wide range of applications, from environmental management and urban planning to resource exploration and agricultural assessment.
What is Surface Analysis?
Surface analysis involves the use of digital elevation models (DEMs) or triangulated irregular networks (TINs) to model continuous surfaces. The objective is to derive and culminate various metrics and visualizations that represent physical geographic features and enable the assessment of spatial trends and patterns.
The core components of surface analysis include:
- Elevation Models: DEMs and TINs represent the surface heights and are crucial for evaluating elevation-related features.
- Slope: This metric evaluates the steepness or incline of a surface, calculated between neighboring cells in a grid-based elevation model.
- Aspect: Aspect analysis determines the compass direction that a slope faces, which is essential for understanding sunlight exposure and radiation.
- Hillshade: This visualization simulates the path and effect of sunlight over the terrain, providing a shadowed relief map for greater terrain visualization.
- Contour Lines: Used to represent the elevation at constant intervals, aiding in the interpretation of terrain shape.
- Viewshed Analysis: Determines visible areas from a specific point, taking into account surface obstructions.
Surface analysis is instrumental in decision-making for land use planning, environmental protection, and infrastructure development.
