BGCSE Geography (Botswana General Certificate of Secondary Education) key terms

A group or chain of many islands scattered across a sea, such as The Bahamas, where hundreds of cays and islands lie spread over shallow banks rather than forming one continuous landmass.

A small, low-lying sandy island, often formed on a reef or sandbar, common throughout The Bahamas and usually too small or dry for permanent settlement.

A broad, shallow submarine plateau of carbonate sediment, such as the Great Bahama Bank, whose depth and pale turquoise water separate the islands and shape local currents and fishing grounds.

A ridge of living coral and limestone built up in warm, clear, shallow tropical seas; it shelters coastlines, supports fish stocks and underpins much Bahamian fishing and tourism.

Salt-tolerant trees with tangled roots that grow in sheltered coastal mudflats and creeks, stabilising sediment, sheltering juvenile fish and buffering the land against storm waves.

A powerful tropical cyclone with sustained winds of at least 119 km/h, forming over warm ocean water and bringing destructive winds, heavy rain and coastal flooding to Bahamian islands.

An abnormal rise in sea level driven ashore by a storm's winds and low pressure, which floods low-lying coastal settlements and causes most hurricane deaths and damage.

A rotating low-pressure system over tropical seas with organised thunderstorm activity and sustained winds of roughly 63 to 118 km/h, one stage below hurricane strength.

Steady winds blowing from the subtropical high-pressure belts towards the equator, arriving in The Bahamas from the northeast and strongly influencing temperature, rainfall and sailing routes.

The drier leeward side of a upland area, where descending air warms and holds more moisture, producing lower rainfall than the windward slopes that receive the rising, cooling air.

The upper surface of saturated rock or soil beneath the ground, which rises and falls with rainfall and determines where wells can supply fresh water on limestone islands.

A body of permeable rock or sediment that stores and transmits groundwater, such as the freshwater lens held within porous Bahamian limestone and tapped by wells.

A sedimentary rock made mainly of calcium carbonate, often formed from compacted shell and coral debris; it underlies most Bahamian islands and dissolves to create caves and sinkholes.

A landscape formed when slightly acidic water dissolves soluble rock such as limestone, producing caves, sinkholes, disappearing streams and uneven bare rock surfaces.

The breakdown of rock in place by physical, chemical or biological processes, such as salt crystallisation and solution, without the material being carried away.

The wearing away and removal of rock or soil by moving agents such as waves, wind, rivers and ice, which shapes coasts and strips exposed land of its fertile layer.

The movement of sand and pebbles along a coast by waves striking the shore at an angle, carrying sediment in a zigzag path and building spits and beaches downdrift.

A gently sloping strip of loose sediment at the shoreline, deposited and reworked by waves and tides, which protects the land behind and attracts tourist development.

The theory that Earth's rigid outer shell is broken into large plates that move slowly over the mantle, causing earthquakes, volcanic activity and the building of mountain belts.

A sudden shaking of the ground caused by the release of built-up stress along a fault or by volcanic activity, measured by magnitude and intensity.

A fracture in the Earth's crust along which rock masses have moved relative to each other, often marking a plate boundary and the source of earthquakes.

The number of live births per 1,000 people in a population in a given year, a key measure of natural increase and of demand for schools and health services.

The number of deaths per 1,000 people in a population in a given year, influenced by healthcare, diet, age structure and living conditions.

The surplus of births over deaths in a population, usually expressed as a rate per 1,000; when positive it causes population growth independent of migration.

A paired bar graph showing the number or percentage of males and females in each age group, revealing a population's age structure and its past fertility and migration history.

The proportion of people too young or too old to work compared with the working-age population, showing how many dependants each worker must support.

The permanent or semi-permanent movement of people from one place to another, driven by push factors such as unemployment and pull factors such as jobs and family ties.

A negative condition at a place of origin, such as unemployment, poor services, drought or insecurity, that encourages people to leave and settle elsewhere.

An attractive condition at a destination, such as higher wages, education, healthcare or family links, that draws migrants towards that place.

The act of leaving one's own country to settle permanently in another; for The Bahamas it describes citizens departing for work or study abroad.

The arrival and settlement of people from another country into a destination country, affecting labour supply, cultural mix and demand for housing and services.

The rising proportion of a country's population living in towns and cities, driven by rural-to-urban migration and natural growth, and bringing pressure on housing and infrastructure.

An area of housing built illegally on unoccupied land without secure title or basic services, often on marginal sites, reflecting a shortage of affordable formal housing.

Development that meets present needs without preventing future generations from meeting theirs, balancing economic growth, social welfare and protection of the environment.

Low-impact travel focused on experiencing and conserving natural environments, designed to fund protection of habitats and benefit local communities rather than degrade them.

The largest population or level of use an area can support without lasting damage to its resources, environment or facilities, a key idea in managing tourism and parks.

The total market value of goods and services produced within a country in a year, used to compare national output and to measure economic growth over time.

The total income earned by a country's residents, including income from abroad, often reported per head to compare living standards between countries.

A composite measure combining life expectancy, education and income per person to rank countries by overall human development rather than by wealth alone.

The ratio between a distance on a map and the same distance on the ground, shown as a statement, representative fraction or linear bar and used to measure real distances.

A set of numbers locating a point on a map by its eastings and northings within the grid squares, quoted with a fixed number of digits to show precision.

A line on a map joining points of equal height above sea level; the spacing of contours shows the steepness of slopes and their pattern reveals valleys and hills.

A straight line drawn across an area along which observations or measurements are recorded, used in fieldwork to show how features change with distance.

Selecting a representative portion of a site or population to measure, using random, systematic or stratified methods, so that findings can be generalised without surveying everything.

The cultivation of crops on ploughed or prepared land, as opposed to rearing livestock, and dependent on soil quality, rainfall and growing season.

A crop grown mainly for sale rather than for the farmer's own consumption, such as pineapples or onions, exposing growers to world price changes.

The artificial supply of water to farmland through channels, pipes or sprinklers, allowing crops to grow where rainfall is insufficient or unreliable.