Page 722 - Geosystems An Introduction to Physical Geography 4th Canadian Edition

G-3 Glossary
Canada Soil Survey Committee. Adapted to Canada’s environment, the CSSC consists of 10 soil orders.
Capillary water (9) Soil moisture, most of which is accessible to plant roots; held in the soil by the water’s surface tension and cohe- sive forces between water and soil. (See also Field capacity, Hygroscopic water, Wilting point.)
Carbonation (14) A chemical weathering process in which weak carbonic acid (water and carbon dioxide) reacts with many minerals that contain calcium, magnesium, potassium, and sodium (especially limestone), transform- ing them into carbonates.
Carbon monoxide (CO) (3) An odourless, colorless, tasteless combination of carbon and oxygen produced by the incomplete combus- tion of fossil fuels or other carbon-containing substances; toxicity to humans is due to its affinity for hemoglobin, displacing oxygen in the bloodstream.
Carbon sink (11) An area in Earth’s atmo- sphere, hydrosphere, lithosphere, or biosphere where carbon is stored; also called a carbon reservoir.
Carnivore (19) A secondary consumer that principally eats meat for sustenance. The top carnivore in a food chain is considered a ter- tiary consumer. (Compare Herbivore.) Cartography (1) The making of maps and charts; a specialized science and art that blends aspects of geography, engineering, mathemat- ics, graphics, computer science, and artistic specialties.
Cation-exchange capacity (CEC) (18) The ability of soil colloids to exchange cations between their surfaces and the soil solution; a measured potential that indicates soil fertil- ity. (See Soil colloid, Soil fertility.) Chaparral (20) Dominant shrub formations of Mediterranean (dry summer) climates; characterised by sclerophyllous scrub and short, stunted, tough forests; derived from the Spanish chaparro; specific to California. (See Mediterranean shrubland.)
Chemical weathering (14) Decomposition and decay of the constituent minerals in rock through chemical alteration of those miner- als. Water is essential, with rates keyed to temperature and precipitation values. Chemi- cal reactions are active at microsites even in dry climates. Processes include hydrolysis, oxidation, carbonation, and solution. Chernozemic (18) A CSSC soil order with well- to imperfectly-drained soils of the steppe–grassland–forest transition in Southern Alberta; Saskatchewan; Manitoba; Okanagan Valley, BC; and Palouse Prairie, BC. Accumulation of organic matter in sur- face horizon.
Chinook wind (8) North American term for a warm, dry, downslope airflow; characteris- tic of the rain-shadow region on the leeward side of mountains; known as föhn or foehn winds in Europe. (See Rain shadow.) Chlorofluorocarbons (CFCs) (3) A manufac- tured molecule (polymer) made of chlorine, fluorine, and carbon; inert and possessing remarkable heat properties; also known as one of the halogens. After slow transport to the stratospheric ozone layer, CFCs react with ultraviolet radiation, freeing chlorine atoms that act as a catalyst to produce reactions that destroy ozone; manufacture banned by inter- national treaties.
Chlorophyll (19) A light-sensitive pigment that resides within chloroplasts (organelles) in leaf cells of plants; the basis of photosyn- thesis.
Cinder cone (13) A volcanic landform of pyroclastics and scoria, usually small and cone-shaped and generally not more than 450 m in height, with a truncated top.
Circle of illumination (2) The division be- tween light and dark on Earth; a day–night great circle.
Circum-Pacific belt (13) A tectonically and volcanically active region encircling the Pacific Ocean; also known as the “Ring of Fire.”
Cirque (17) A scooped-out, amphitheater- shaped basin at the head of an alpine glacier valley; an erosional landform.
Cirrus (7) Wispy, filamentous ice-crystal clouds that occur above 6000 m and appear in a variety of forms, from feathery hairlike fibers to veils of fused sheets.
Classification (10) The process of ordering or grouping data or phenomena in related classes; results in a regular distribution of information; a taxonomy.
Climate (10) The consistent, long-term be- haviour of weather over time, including its variability; in contrast to weather, which is the condition of the atmosphere at any given place and time.
Climate change science (11) The interdisci- plinary study of the causes and consequences of changing climate for all Earth systems and the sustainability of human societies.
Climate feedback (11) A process that either amplifies or reduces a climatic trend toward either warming or cooling.
Climatic region (10) An area of homogenous climate that features characteristic regional weather and air mass patterns.
Climatology (10) The scientific study of cli- mate and climatic patterns and the consistent behavior of weather, including its variability and extremes, over time in one place or re- gion; includes the effects of climate change on human society and culture.
Climograph (10) A graph that plots daily, monthly, or annual temperature and precipi- tation values for a selected station; may also include additional weather information.
Closed system (1) A system that is shut off from the surrounding environment, so that it is entirely self-contained in terms of en- ergy and materials; Earth is a closed material system. (Compare Open system.)
Cloud (7) An aggregate of tiny moisture droplets and ice crystals; classified by alti- tude of occurrence and shape.
Cloud-albedo forcing (4) An increase in albedo (the reflectivity of a surface) caused by clouds due to their reflection of incoming insolation.
Cloud-condensation nuclei (7) Microscopic particles necessary as matter on which water vapour condenses to form moisture droplets; can be sea salts, dust, soot, or ash.
Cloud-greenhouse forcing (4) An increase in greenhouse warming caused by clouds be- cause they can act like insulation, trapping longwave (infrared) radiation.
Col (17) Formed by two headward-eroding cirques that reduce an arête (ridge crest) to form a high pass or saddlelike narrow depression.
America.
Cold front (8) The leading edge of an ad- vancing cold air mass; identified on a weather
map as a line marked with triangular spikes pointing in the direction of frontal move- ment. (Compare Warm front.)
Community (19) A convenient biotic subdi- vision within an ecosystem; formed by inter- acting populations of animals and plants in an area.
Composite volcano (13) A volcano formed by a sequence of explosive volcanic eruptions; steep-sided, conical in shape; sometimes re- ferred to as a stratovolcano, although com- posite is the preferred term. (Compare Shield volcano.)
Conduction (4) The slow molecule-to- molecule transfer of heat through a medium, from warmer to cooler portions.
Cone of depression (9) The depressed shape of the water table around a well after active pumping. The water table adjacent to the well is drawn down by the water removal.
Confined aquifer (9) An aquifer that is bounded above and below by impermeable layers of rock or sediment. (See Artesian wa- ter, Unconfined aquifer.)
Constant isobaric surface (6) An elevated surface in the atmosphere on which all points have the same pressure, usually 500 mb. Along this constant-pressure surface, isobars mark the paths of upper-air winds.
Consumer (19) Organism in an ecosystem that depends on producers (organisms that use carbon dioxide as their sole source of car- bon) for its source of nutrients; also called a heterotroph. (Compare Producer.)
Consumptive use (9) A use that removes water from a water budget at one point and makes it unavailable farther downstream.
Continental divide (15) A ridge or elevated area that separates drainage on a continental scale; specifically, that ridge in North Ameri- ca that separates drainage to the Pacific on the west side from drainage to the Atlantic and Gulf on the east side and to Hudson Bay and the Arctic Ocean in the north.
Continental drift (12) A proposal by Alfred Wegener in 1912 stating that Earth’s land- masses have migrated over the past 225 mil- lion years from a supercontinent he called Pangaea to the present configuration; the widely accepted plate tectonics theory today. (See Plate tectonics.)
Continental effect (5) A quality of regions that lack the temperature-moderating effects of the ocean and that exhibit a greater range of minimum and maximum temperatures, both daily and annually, than do marine sta- tions. (See Marine effect, Land–water heating difference.)
Continental landmass (13) The broadest category of landform, including those masses of crust that reside above or near sea level and the adjoining undersea continental shelves along the coastline; sometimes synonymous with continental platforms.
Continental shield (13) Generally, old, low- elevation heartland regions of continental crust; various cratons (granitic cores) and an- cient mountains are exposed at the surface.
Convection (4) Transfer of heat from one place to another through the physical move- ment of air; involves a strong vertical motion. (Compare Advection.)
Convectional lifting (8) Air passing over warm surfaces gains buoyancy and lifts, ini- tiating adiabatic processes.
Convergent lifting (8) Air flowing from dif- ferent directions forces lifting and displacement of air upward, initiating adiabatic processes.
Cold desert and semidesert (20)
A type of desert biome found at higher latitudes than warm deserts. Interior location and rain shadows produce these cold deserts in North