Lecture Notes on Coordinate Systems, Map Projections, and Surveying

Vocabulary flashcards for key terms and concepts from the lecture notes.

Geoid

A model of mean sea level used as a vertical datum for measuring elevation.

Orthometric Height (H)

Height above the geoid.

Ellipsoid

A smooth mathematical approximation of the Earth (flattened sphere) used for calculating latitudes and longitudes.

Ellipsoidal Height (h)

Height above the ellipsoid.

Geoid Undulation (N)

The difference between the ellipsoid and geoid at a location.

Map Projection

A way to project lat/lon onto an (x, y) plane because the Earth is curved (3D) and maps are flat (2D).

Mercator Projection

A cylindrical map projection that preserves angles, making it good for navigation, but distorts area near the poles.

Transverse Mercator (T-M)

A cylindrical map projection where the cylinder is turned sideways (transverse), making it more accurate for narrow N-S zones.

UTM (Universal Transverse Mercator)

A global coordinate system that uses 60 zones, each 6° wide, based on the Transverse Mercator projection, giving (x, y) coordinates in meters.

Azimuth

Angle measured clockwise from true North, ranging from 0° to 360°.

Bearing

Angle within a quadrant (0° < α < 90°) labeled with direction (e.g., N45°E), indicating the direction from North/South.