GTLE Geography key terms

The branch of geography studying natural features and processes of Earth's surface, including landforms, climate, soils, water bodies, and vegetation, apart from human activity.

The branch of geography examining how people organize space, including population distribution, settlement, culture, economic activity, and the human use and alteration of environments.

The art and science of designing, producing, and interpreting maps, including decisions about projection, scale, symbols, and generalization used to represent Earth's surface.

The ratio between distance on a map and the corresponding distance on the ground, shown as a representative fraction, verbal statement, or graphic bar.

A systematic method of transferring positions from the curved Earth onto a flat surface, necessarily distorting some combination of shape, area, distance, or direction.

An angular grid of imaginary lines used to locate points on Earth: parallels of latitude measured north and south of the equator, and meridians of longitude measured east and west of the prime meridian.

Collecting information about Earth's surface from a distance, typically using aircraft or satellite sensors that record reflected or emitted energy across visible, infrared, or radar wavelengths.

A computer system for capturing, storing, analyzing, and displaying spatially referenced data, allowing layers of information to be combined and queried by location.

A map designed to show the spatial distribution of a single theme or variable, such as population density, rainfall, or land use, rather than general reference features.

A thematic map in which predefined areas such as countries or census tracts are shaded or patterned in proportion to the value of a variable, revealing regional patterns at a glance.

A line on a map connecting points of equal value for some continuous variable, such as elevation (contour), temperature (isotherm), or atmospheric pressure (isobar).

An isoline on a topographic map joining points of equal elevation above a datum, whose spacing indicates slope steepness and whose shape reveals ridges, valleys, and depressions.

A large-scale map depicting elevation and terrain through contour lines along with natural and cultural features such as streams, roads, and buildings.

The process of simplifying map detail as scale decreases, selecting and smoothing features so the map stays legible while preserving essential spatial patterns.

The theory that Earth's rigid outer shell is divided into plates that move over the asthenosphere, explaining earthquakes, volcanism, mountain building, and the distribution of continents.

A fracture in rock along which movement has occurred, releasing stored strain as earthquakes; faults are classified as normal, reverse, or strike-slip by the direction of displacement.

Weathering breaks rock down in place through physical, chemical, or biological processes, while erosion transports the resulting debris by water, wind, ice, or gravity.

A recognizable natural feature of Earth's surface, such as a mountain, plateau, plain, valley, or delta, shaped by tectonic uplift and erosional or depositional processes.

The variation in elevation and slope across an area, often described by the difference between its highest and lowest points and depicted on maps by shading or contours.

The long-term average and variability of weather conditions at a place, typically summarized over thirty years and controlled by latitude, altitude, distance from water, and prevailing winds.

The short-term state of the atmosphere at a given place and time, described by temperature, humidity, precipitation, wind, and pressure.

A large body of air with relatively uniform temperature and humidity acquired over a source region, such as polar continental or maritime tropical, whose movement drives weather changes.

The boundary zone where two air masses of different density meet; warm, cold, stationary, and occluded fronts each produce characteristic cloud and precipitation patterns.

A large ecological region characterized by a distinctive climate and dominant plant life, such as tropical rainforest, savanna, desert, temperate grassland, or tundra.

A community of living organisms interacting with one another and with their nonliving environment, exchanging energy and cycling nutrients through food webs.

The variety of life within a place, encompassing genetic variation, species richness, and the diversity of ecosystems, which supports resilience and ecosystem services.

The continuous circulation of water among oceans, atmosphere, and land through evaporation, transpiration, condensation, precipitation, runoff, and groundwater flow.

The entire area of land that drains rainfall and snowmelt to a common outlet such as a river, lake, or ocean, bounded by topographic divides.

A body of rock or sediment that stores and transmits groundwater in usable quantities, recharged by infiltration and often tapped by wells.

The growing share of a population living in cities and towns, accompanied by the physical expansion of built-up areas and shifts in land use and employment.

A metropolitan area with a population exceeding ten million people, often marked by rapid growth, sprawling peripheries, and severe infrastructure and housing pressures.

The number of people per unit area, usually persons per square kilometer, used to compare how crowded or sparsely settled regions are.

The pattern of where people live across Earth's surface, shaped by climate, relief, soils, water supply, economic opportunity, and historical settlement.

Conditions that drive people away from a place, such as conflict or unemployment, and conditions that attract them elsewhere, such as jobs or safety, together explaining migration.

A region, usually about fifteen degrees of longitude wide, that keeps a uniform standard time, with local time advancing eastward and lagging westward from the prime meridian.

A generally north-south line through the Pacific Ocean near the 180th meridian where the calendar date changes by one day when crossing.

A main river together with all its tributaries and distributaries, draining a watershed and shaping valleys, floodplains, and deltas along its course.

The laying down of eroded sediment when transport energy declines, building features such as deltas, floodplains, sandbars, and moraines.

The large-scale removal of forest cover, typically for agriculture or logging, which alters hydrology, reduces biodiversity, and can accelerate soil erosion and carbon emissions.