Maps are visual representations of an area – a symbolic depiction highlighting relationships between elements of that space such as objects, regions, and themes. Cartographers create various types of maps, broadly categorized as general reference and thematic maps, each serving unique purposes. Understanding “What Is Maps” requires exploring these categories and their applications, including the modern use of Geographic Information Systems (GIS).
General Reference Maps
General reference maps provide a broad overview of geographic information. They show the locations of cities, boundaries, roads, mountains, rivers, and coastlines. These maps are designed to offer a comprehensive understanding of the spatial arrangement of features in a given area. A key example of organizations producing these maps is the U.S. Geological Survey (USGS).
Topographic maps are an important subset of general reference maps. These maps display changes in elevation, illustrating hills and valleys. Contour lines connect points of equal elevation, enabling users to visualize the terrain’s shape and steepness. This information is valuable for hikers planning routes and engineers determining locations for infrastructure projects like highways and dams. Furthermore, geologic maps fall under general reference maps, showing bedrock formations, sediment deposits, and geological structures.
Thematic Maps
Thematic maps focus on specific distributions or patterns across the Earth’s surface. They emphasize a single theme or topic, such as population density, average income, or language distribution. Thematic maps are designed to communicate information about people, other organisms, or the environment.
Historically, Sanborn maps were created for fire insurance companies. These maps provided detailed information about buildings, including outlines, size, shape, construction materials, heights, and functions. This allowed insurers to assess the risk associated with insuring properties accurately.
GIS Maps: A Modern Approach
Many thematic maps are now created using Geographic Information System (GIS) technology. GIS are computer systems that capture, store, and display data related to geographic positions. This technology combines map information with diverse data sets, including information about people, land, climate, farms, houses, and businesses. Displaying multiple data layers on a single map enables complex analysis and informed decision-making.
GIS technology is utilized across various industries and government sectors. For example, officials use GIS data to identify streams at high risk of pollution. Businesses use GIS to determine optimal locations for new stores, considering factors like demographics and accessibility.
Topographic Maps in Detail
Topographic maps are distinguished by their use of elevation contour lines, which depict the shape of the Earth’s surface. These imaginary lines connect points with the same elevation above or below a reference surface, typically mean sea level.
Contour lines enable topographic maps to represent the height and shape of mountains, the depth of ocean floors, and the steepness of slopes, offering a detailed depiction of terrain. This level of detail makes topographic maps essential tools for various applications, from recreational activities to professional engineering projects.
In conclusion, understanding “what is maps” involves recognizing the diverse types available, their specific purposes, and the impact of modern technologies like GIS. From general reference maps providing broad geographic context to thematic maps highlighting specific patterns and distributions, maps are invaluable tools for understanding our world.
