Physical Geography - Maps, Scales, and Projections

Vocabulary flashcards generated from Physical Geography Chapter 2 notes, detailing map projections, scales, elements, survey systems, and spatial data types.

International Date Line

The line where the calendar day begins, located exactly 12 hours ahead of Greenwich time and 12 hours behind; at the exact moment of midnight on this line, it is the same calendar day all over the world.

Township & Range Survey System

A survey system established in 1785 used to locate land areas in much of the U.S., especially west of Pennsylvania.

Map

A generalized view of an area, as seen from above and reduced in size, serving as a core tool for geographers to understand human and environmental patterns.

Scale

The ratio of map units to ground units.

Map Projection

A method or process of transforming Earth's curved spherical surface onto a flat map using mathematical models or projection techniques (e.g., planar, conic, cylindrical).

Cartography

The art and science of mapmaking, facing the challenge of creating flat maps out of a spherical world.

Planar Projection

A map projection best for polar regions that shows one hemisphere from a top-down view.

Conic Projection

A map projection ideal for mid-latitudes like the U.S. that features minimal distortion in those regions.

Cylindrical Projection

A map projection (e.g., Mercator) that maintains true compass directions but distorts size, especially near the poles.

Conformal Maps

Maps that preserve correct shapes (e.g., Mercator projection) while distorting area, causing Greenland to appear much larger than it really is.

Equal-Area Maps

Maps that preserve the relative size of land areas.

Gnomic Projection

A map projection useful for navigation where straight lines between 2 points portray great circle routes and distortion increases outward.

Mercator Projection

A projection designed for navigation that uses straight lines for both meridians and parallels crossing at right angles, where a straight line represents a line of true compass bearing.

Title (Map Element)

A key map feature that explains the subject and location of the map.

Date (Map Element)

A key map feature that shows when data was collected.

Legend (Map Element)

A key map feature that explains symbols and color codes.

Direction (Map Element)

A key map feature that usually includes a north arrow.

Verbal Scale

A scale expressed as a statement like "1 inch = 1 mile" that is easy to read, but not reliable if the map is resized.

Graphic Scale (Bar Scale)

A scale that acts like a ruler and remains accurate even if the map is resized.

Representative Fraction (RF)

A scale expressed as a ratio like $1:63{,}360$, meaning 1 unit on the map represents $63{,}360$ units on the ground.

Small-Scale Map

A map showing a large area with less detail, such as $1:100{,}000$.

Large-Scale Map

A map showing a small area with more detail, such as $1:24{,}000$.

Discrete Data

Spatial data that exists at specific locations rather than everywhere (e.g., hot springs, rivers, tornado paths, earthquake faults) and appears as points, lines, or areas on maps.

Point Symbols

Map symbols used to depict discrete data at specific points, such as earthquake locations and lightning strikes.

Line Symbols

Map symbols used to depict linear discrete data, such as hurricane paths, rivers, and fault lines.

Area Symbols

Map symbols used to depict discrete spatial areas, such as burned land, watersheds, and storm impact zones.

Reference Maps

A type of map that displays both human and natural objects with an emphasis on location.