Final Exam Flashcards
how steep a river’s slope is
Gradient
how much water does a river hold
Discharge
where a river meets the sea
Delta
straight channels in a narrow valley or slot canyon slopes; prone to flash floods
Young river
gently curved channels in wider floodplains; prone to ice-jam floods
Mature river
extremely curved channels in very wide floodplains; prone to levee-burst floods
Old-age river
made of loose mud that compacts and sink
Deltas
piles of loose sand that wash away in hurricanes
Barrier islands
Sun and Moon both pull tides higher at the same time
King tides
caused by king tides
Sunny-day floods
bulge of water created by hurricanes
Storm surges
shock waves created by undersea earthquakes or landslides
Tsunami
water vapor rises from the ocean
Evaporation
wind moves through the atmosphere
Circulation
water condenses and falls back to the ground
Precipitation
water flows through rocks and soils back to rivers, lakes, and ocean
Groundwater flow
tiny holes in rocks and soil where water flows
Pores
rain soaks into the ground
Recharge
groundwater comes out at the surface
Discharge
how much empty space is present
Porosity
how well are the pores connected to each other
Permeability
any rock or sediment that can carry water (high permeability, high porosity)
Aquifer
may store water, but can’t allow it to move (low permeability)
Aquiclude
wet zone formed when groundwater flows out from a hillside
Seep
groundwater focused in a fracture or bedding plane
Spring
thin zone of wet rocks above the real water table
Perched water table
water table is lowered by pumping from a water well
Cone of depression
boundary between damp rocks (unsaturated zone) and wet rocks (saturated zone)
Water table
area where the water table lies right at the ground surface
Wetland
landscape formed by dissolution of limestone and other soluble rocks
Karst
rivers that flow down into caves
Sinking streams
collapsed cave
Sinkholes
cold air sinks and dries out
High pressure
warm air rises and water condenses out
Low pressure
formed by global bands of high air pressure
Subtropical deserts
cold, dry areas of high pressure at the poles
Polar deserts
caused by mountains blocking rising air (orographic effect)
Rain-shadow deserts
formed in the center of large continents or supercontinents
Interior deserts
caused by cold ocean currents that create fog rather than rain
Coastal deserts
sand-blasted rock formations
Ventifacts
larger pebbles left behind as wind blows dust and sand away
Desert pavements
dry thunderstorms that pick up sand and silt
Haboob
a body of ice that flows downhill
Glaciers
snow that has compacted and becomes solid
Firn
snow piles up at the head (upper end) of a glacier
Accumulation
ice melts and sediment drops out at the toe (lower end) of a glacier
Ablation
glacier grows longer as climate cools
Advance
glacier shrinks as climate warms
Retreat
small ‘baby’ glacier in a mountain hollow
Cirque glacier
river of ice flowing between mountains
Valley glacier
blanket of ice over a mountain range, carving them into sharp ‘horns
Ice caps
valley glaciers that reach a lake or ocean
Fjord glaciers
spread out into an icy fan at the foot of mountains
Piedmont glaciers
enormous blankets of ice that cover large parts of continents
Ice sheets
ridge formed by glacial sediment
Moraine
unsorted, messy sediment dropped by glaciers
Till
any time when large ice sheets exist
Ice age
shorter warm periods between glaciations
Interglacials
times when ice sheets advance to cover wide areas
Glaciations
changes in shape or angle of the Earth’s orbit
Orbital cycles
lower levels of carbon dioxide cool the climate
Reverse greenhouse
dust, ash, and smoke block sunlight
Global dimming
the color of the ground surface either reflects or absorbs light energy
Albedo
long-term average of weather
Climate
warm and mild, no ice, high carbon dioxide levels
Greenhouse climate
poles are cold, lots of ice, low carbon dioxide levels
Icehouse climate
