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Earth and the Environment
Final
206
Geology
Undergraduate 1
05/09/2010

Additional Geology Flashcards

 


 

Cards

Term
mass wasting
Definition
the downslope movement of rock, regolith, and soil under the direct influence of gravity
Term
gravity
Definition
has a component parallel and a component perpendicular to the surface
Term
angle of repose and how it changes for different materials
Definition
has a component parallel and a component perpendicular to the surface
- Dry materials usually 30-37 degrees, increasing with increasing grain size
-Slightly wet materials have a very high angle
-Saturated in water has a very low angle of repose
Term
rock falls
Definition

often aided by frost wedging in joints, fastest movement and rock can become air born, results in talus

[image]

Term
rock slides
Definition

occur when blocks of bedrock break loose and slide down a slope. Usually occur where rock strata are inclined or where joints and fractures exist parallel to the slope, and often aided by rain or melting snow that decreases friction, leads to scarp surfaces above and hummocky rocks below

[image]

Term
debris flow
Definition

a relatively rapid type of mass wasting including mud, earth, and debris, more fluid to preponderance of water, often channelized masses speeding at around 50 mph, frequent in southern California

[image]

Term
debris slide
Definition

like a rock slide except debris is largely unconsolidated

[image]

Term
slump
Definition

ike slides, but involve coherent masses, most common along beach cliffs and stream valleys

[image]

Term
creep
Definition

slowest and most widespread form of slope failure, almost imperceptible downhill movement caused by swelling and shrinking of soil in response to freezing and expanding of water in pores (soliflunction) and absorption of water and expansion of clay materials

[image]

Term
scarp
Definition
at top of a landslide, hollowed out from rapid escape of rocks
Term
hummocky ground
Definition
below landslide, lots of little hills up and down from debris
Term
subsidence
Definition
ground surface sags gently or drops catastrophically as voids in rocks close, creates sinkholes
Term
7 main indications for landslides
Definition
steep slopes, soft rocks, fractures, water, dip-slope conditions, loss of vegetation, prior history (scarps and hummocky ground
Term
methods of landslide mitigation
Definition
anchors, soil removal, steel “piles” used to tie the landslide mass with the rocks below, surface drainage ditches designed to collect and remove rain water
Term
watershed
Definition
the area in which all the water drains into a specific river, ocean, etc
Term
dendritic drainage
Definition
most common, horizontal or uniformly dipping beds
Term
radial drainage
Definition
water is draining radially around mountains, from the top down
Term
rectangular drainage
Definition
occurs do to jointed, fractured rocks, rivers move at sharp angles
Term
trellis drainage
Definition
a system of streams in which nearly parallel tributaries occupy valleys cut in folded strata
Term
drainage density
Definition
due to permeability of the rocks
Term
dissolved load
Definition
sediment is in solution, usually acquired by groundwater and dispersed throughout the flow, velocity has no effect on a streams ability to carry a dissolved load, and the quantity of the load is highly variable
Term
suspended load
Definition
small particles in suspension, type and amount of material carried controlled by velocity of the water and the settling velocity of each sediment grain (larger particles settle faster)
Term
bed load
Definition
solid materials moving along the bottom of the stream, has an important effect on erosion of stream beds
Term
deposition vs transportation vs erosion (what controls it
Definition
Level of water depth and velocity and particle size controls deposition vs transportation vs erosion, during flood stage erosion, transportation at normal levels and deposition at low river levels
Term
turbulent water
Definition
eddies, particles of water move in all directions
Term
laminar water
Definition
all particles move in the same direction straight down river
Term
water velocity at different points in a stream
Definition
maximum at deepest part of river, faster around cut banks (outside of turns) then at point bars (inside of turns)
---More erosion at cut bank and deposition at point bar
Term
meandering rivers
Definition
low gradient and unconsolidated sediment – erode
Term
braided river
Definition
steep slopes, lots of bed load (coarse material), erodible banks, variable discharge
Term
flood plain
Definition
the flat, low-lying portion of a stream valley subject to periodic inundation
Term
longitudinal stream profile
Definition
a cross section of a stream channel along its descending course from the head to the mouth
--High on the profile – more youthful streams, v-shaped walls, high velocity
--Low on profile - mature streams, large flood plains (wide river valleys), U shaped walls if at all, often meandering or braided, deposition matches erosion
Term
base level
Definition
the level below which a stream cannot erode
Term
delta
Definition
an accumulation of sediment formed where a stream enters a lake or an ocean
Term
alluvial fan
Definition
a fan shaped deposit of sediment formed when a stream’s slope is abruptly reduced
Term
cutoff/oxbow lake
Definition
formed when a meandering stream cuts of a loop over time, leaving a shorter path and a loopy lake not connected to anything
Term
causes and types of floods
Definition
--Local thunderstorm – flash flood lasting a few hours
--Rainfall over weeks – regional floods lasting weeks, building and dissipating slowly, often also do to snow melt
--Dam breaks – short lived natural dams (landslide, log and ice jam, lahar) cause flooding up stream, and then flash floods downstream when they break, human built levees or dams fail in floods
Term
hydrograph
Definition
flood occurs some time lag after rainfall occurs because it takes time for runoff to reach river
Term
impact of dams
Definition
--Pros – clean energy, water, farming, recreation
--Cons – sediment trap, impact on beaches and wildlife (salmon)
--Can break unexpectedly causing huge disasters
Term
flood recognition
Definition
--Recent – debris, sand bars, gravel/boulders
--Historical – gravel and sand intervals (date with carbon), flood hazard maps
Term
Levees
Definition
artificial mounds built on the banks of a river to increase the volume of water the channel can hold
Term
channelization
Definition
altering a stream channel in order to speed the flow of water to prevent it from reaching flood height
Term
darcy's law
Definition
An equation stating that groundwater discharge depends on the hydraulic gradient, hydraulic conductivity, and cross sectional area of an aquifer
Term
what is groundwater flow dependent on
Definition
permeability and slope of water table surface
Term
porosity
Definition
% of open space
Term
permeability
Definition
how well the space is connected allowing groundwater to flow
Term
ground water table
Definition
upper limit of where groundwater exists
Term
perched water table
Definition
a localized zone of saturation above the main water table, created by an impermeable layer (aquiclude)
Term
confined aquifer
Definition
between two aquitards (impermeable layers)
Term
aquifer
Definition
rock or sediment through which groundwater moves easily
Term
aquitard
Definition
an impermeable bed that hinders or prevents groundwater movement
Term
vadose zone
Definition
unsaturated zone, above the water table
Term
gaining or losing stream
Definition
streams that gain water from the inflow of groundwater through the stream bed, or that lose water from the to the groundwater system by outflow through the stream bed
Term
cone of depression
Definition
a cone shaped depression in the water table immediately surrounding a well
Term
artesian well
Definition
groundwater under pressure rises above the level of the aquifer. Usually occurs where a confined water table is at an incline, so there is pressure at the bottom which pushes the water up
Term
springs
Definition
where water table intersects land surface, often on faults or at a raised groundwater table
Term
how do groundwater properties change with depth
Definition
gets harder, hotter, older, and less abundant with depth
Term
how is water hardness measured
Definition
by quantities of Ca and Mg in ppm
Term
caverns
Definition
created at or just below the water table where acidic groundwater follows lines of weakness in the rocks such as joints and absorbs water
Term
karst topography
Definition
areas that typically have irregular terrain punctuated with many sinkholes, often lack streams bc water is funneled straight underground
Term
formation of sinkholes
Definition
caverns collapse under their own weight or limestone slowly dissolves the rock from the surface
Term
hot springs
Definition
due to volcanic rocks, or formed deep where the earth is naturally very warm so water is heated
Term
geysers
Definition
hot rocks underground create steam from water which raises pressure
Term
travertine
Definition
platforms formed by hot springs and geysers
Term
groundwater mining
Definition
hen excessive wells make a noticeable effect on the water table, creating a cone of depression
Term
excessive wells
Definition
cause the drying of lakes and streams and a drop in the level of the water table
Term
contaminants in groundwater pollution
Definition
feedlots, food processing spills, septic tanks, sewage spills, heavy metals, acid mine waste toxic compounds
Term
eutrophication
Definition
excess nutrients leads to excessive plant growth which decreases oxygen content of the water
Term
accumulation
Definition
requires not only cool summers but also precipitation
Term
ablation
Definition
melting, iceberg calving, sublimation, wind erosion
Term
glacial flow
Definition
rotation, melting and refreezing, sliding
--Upper layer is brittle so it forms cracks and crevices
--Lower layer is ductile so it folds and flows continuously
Term
valley glacier
Definition
relatively small glaciers existing in mountain areas, usually flowing in valleys previously occupied by streams
Term
continental glacier
Definition
much larger then valley glaciers, cover a whole continent, only 2 exist today, Antarctica and Greenland
Term
medial moraine
Definition
a ridge of till formed when lateral moraines from two coalescing alpine glaciers join
Term
lateral moraine
Definition
a ridge of till along the sides of a valley glacier composed primarily of debris that fell to the glacier from the valley walls
Term
end morain
Definition
a ridge of till marking a former position of the front of a glacier
Term
horn
Definition
a pyramid like peak formed by glacial action in three of more cirques surrounding a mountain summit
Term
arete
Definition
a narrow knifelike ridge separating two adjacent glaciated valleys
Term
cirque
Definition
an ampitheatre shaped basin at the head of a glaciated valley produced by frost wedging and plucking
Term
tarn
Definition
a small lake in a cirque
Term
glacial striations
Definition
scratches or grooves in a bedrock surface caused by the grinding action of a glacier and its load of sediment
Term
glacial till
Definition
unsorted sediment deposited directly by a glacier
Term
glacial erratic
Definition
ice transported boulders that were not derived from the bedrock near their present site
Term
kame
Definition
a steep sided hill composed of sand and gravel, originating when sediment collected in openings in stagnant glacial ice
Term
kettle hole
Definition
depressions created when blocks of ice become lodged in glacial deposits and subsequently melt, called a kettle lake when this is below the water table
Term
varve
Definition
coupled markings in rocks that show seasons during glaciations
Term
permafrost
Definition
rock or soil frozen for at least 2 years, destabilizes manmade/natural structures
Term
desertification
Definition
as glaciers are shrinking, the earth’s deserts are growing
Term
causes of desertification
Definition
global warming, overgrazing, groundwater depletion, irrigation induced soil salinization, deforestation, urbanization, mining without reclamation, wind as an agent of erosion and deposition
Term
polar desert
Definition
perpetual snow cover but low precipitation (Antarctica and Greenland)
Term
sub tropical desert
Definition
latitudes around 25 degrees, pressure pushes moisture towards the equator, Sahara, Arabian, and Sonora deserts
Term
deep interior desert
Definition
Gobi of China and Mongolia
Term
coastal desert
Definition
downwind of mountain ranges, eastern Washington, Oregon, California (Mojave)
Term
rain shadow desert
Definition
similar to rain shadow, except winds off the continent are stripped of moisture by mountains, Ex. Atacama desert of Chile
Term
deflation
Definition
the lifting and removal of loose material by wind
Term
desert pavement
Definition
a layer of coarse pebbles and gravel created when wind removes the finer material
Term
ventifact
Definition
a cobble or pebble with flat abraded surfaces polished and shaped by the sandblasting effect of wind,
Term
desert varnish
Definition
coating of rocks caused by water evaporating off the surface of the rock and depositing minerals that were in solution
Term
causes of the southern dustbowl
Definition
o Deep plowing of the topsoil killed natural grasses that helped hold topsoil in place and trapped moisture even during droughts and high winds
Term
Inselberg
Definition
an isolated mountain remnant characteristic of the late stage of erosion in a mountainous or arid region
Term
Pediment
Definition
broad, slightly sloping bedrock surface at base of steeper slope, often covered with interlocked, loosely cemented gravel
Term
alluvial fan
Definition
a fan shaped deposit of sediment formed when a stream’s slope is abruptly reduced
Term
bajada
Definition
an apron of sediment along a mountain front created by the coalescence of alluvial fans
Term
playa
Definition
the flat central area of an undrained desert basin
Term
barchan dune
Definition

a solitary sand dune shaped like a crescent with its tips pointing downwind

[image]

Term
transverse dune
Definition

a series of long ridges oriented at right angles to the prevailing wind; these dunes form where vegetation is sparse and sand is very plentiful

[image]

Term
longitudinal dune
Definition

long ridges of sand oriented parallel to the prevailing wind; these dunes form where sand supplies are limited

[image]

Term
parabolic dune
Definition

a sand dune similar in shape to a barchans dune except that its tips point into the wind. These dunes often form along coasts that have strong onshore winds, abundant sand, and vegetation that partly covers the sand

[image]

Term
star dune
Definition

an isolated hill of sand that exhibits a complex form and develops where wind directions are variable

[image]

Term
cross bedding
Definition

form bc of wind carrying sand particles, as wind directions change the direction of particle motion changes, creating layers of different sloping dunes --wind is pointing in direction of slope of cross bedding

[image]

Term
waves
Definition
traveling energy, formed by some transfer of energy that may happen far out at sea, often by wind
Term
how does water move
Definition
in a circular motion
Term
wave base
Definition
where there is negligible water movement, usually below a depth of ½ wavelength
Term
break
Definition
When waves “feel bottom” (depth is equal to wave base) they begin to move slower allowing faster waves out at sea to catch up, thus decreasing speed and wavelength and increasing height. When wave can no longer support itself it breaks
Term
wave refraction
Definition
the bending of waves, leads to stronger wave impact against the sides and ends of headlands, and lower impact in bays
Term
longshore drift
Definition
even with wave refraction, waves typically hit beaches at some angle, which can move sand and sediment downshore
Term
groin
Definition
a short wall built at a right angle to the seashore to trap moving sand
Term
breakwater
Definition
a structure protecting a nearshore area from breaking waves, built further out in the water not right on shore
Term
jetties
Definition
a pair of structures extending into the ocean at the entrance to a harbor or a ricer that are built for the purpose of protecting against storm waves and sediment deposition
Term
wave cut cliffs
Definition
originate by the cutting action of the of surf against the base of coastal land
Term
marine terrace formation
Definition
wave cut bench is uplifted above sea level by tectonic forces
Term
sea arches
Definition
formed when softer or more highly fractured rocks erodes in a headland at a faster rate creating an arch
Term
sea stacks
Definition
forms when the arch collapses leaving an isolated remnant
Term
submerged shoreline
Definition
water level rises so shoreline moves up
Term
estuary
Definition
sea flooded river valley
Term
spit
Definition
an elongated ridge of sand that projects from the land into the mouth of an adjacent bay
Term
barrier island
Definition
low ridges of land parallel to the coast at distances from 3-30 km offshore
Term
tombolo
Definition
a ridge of sand that connects an island to the mainland or to another island, forms in the same manner as a spit
Term
bay mouth bar
Definition
a spit that closes a bay
Term
composition of the atmosphere
Definition
78% N2, 20% CO2, trace amounts of CO2, H2O is variable
Term
greenhouse gases responsible for temperature change
Definition
CO2, H2O, CH4, etc
Term
layers of the atmosphere
Definition
[image]
Term
uneven heating of the earths surface
Definition
at poles: rays strike surface at low angle and heat us diffuse
at equator: rays are perpendicular, maximum heating occurs
Term
where does maximum precipitation and evaporation happen
Definition
precipitation is greatest at equator, evaporation is greatest 10-40 degrees above and below equator
Term
properties of ocean water
Definition
temperature, salinity/composition, density, stratification
Term
near surface circulation
Definition
caused by the wind and the continents
Term
deep surface circulation
Definition
driven by density because cold and +/- saline water sinks at high latitudes, important for earths climate
Term
cyclicity of climate
Definition
approx one ice age event every 100,000 years
Term
insolation
Definition
INcoming SOLar radiation, varies with season, earths axis inclined with respect to elliptic orbit
Term
milkanovich cycle
Definition
occur every 20,000-40,000 years, with accelerated diminished solar radiation every 100,000 years
Term
How do temperature and greenhouse gas concentration interact
Definition
as T increases, GHG concentration also increases
Term
sea floor sediment
Definition
numbers and types of organisms living near sea surface, and thus later in sediment, change with the climate
Term
oxygen isotope analysis
Definition
during periods when glaciers are extensive, concentration of O18 increases in water, and during warmer periods there are less glaciers so O18 concentration drops compared to O16
--We can look at this ratio over time in the record of shells of microorganisms
Term
ice core analysis
Definition
air bubbles record variations in atmospheric composition, changes in CO2 and CH4 are linked to fluctuation temperatures, also include atmospheric fallout such as wind-blown dust, volcanic ash, pollen, and pollution
Term
tree rings
Definition
a new ring is formed each year, characteristics of each ring such as size and density reflect environmental conditions that prevailed during the year when the ring formed
Term
causes of global warming
Definition
pollution, 2 types, combustion (pollutant is a direct product of reaction) and photochemical (sunlight is needed)
Term
Greenhouse effect
Definition
radiation is reflected by the earth’s surface, and sometimes it is trapped by greenhouse gasses and re-emitted in all directions instead of exiting the atmosphere as it normally would
Term
how are greenhouse gases produced
Definition
by industry, automobiles, etc
Term
effects of global warming
Definition
sea level rise and loss of shorelines, increased severe weather, increased disease, animal extinction and people not being able to grow the crops they are used to
Term
carbon sources
Definition
animal respiration, industry, volcanic eruptions
Term
carbon sinks
Definition
plant respiration, oceans, carbon stored in rocks over millions of years
Term
renewable energy
Definition
wind, solar, hydroelectric, biomass, fusion
Term
non-renewable energy
Definition
fossil fuels and nuclear
Term
fossil fuels
Definition
derived from past life forms, organic material
Term
when did shift from wood to coal to oil happen
Definition
o Wood used originally, shift to coal after widespread deforestation during industrial revolution, ~1940 widespread shift to oil and gas began
Term
worlds largest coal reserves
Definition
in the US, next largest in China and Russia, enough coal to last until 2300
Term
worlds largest oil reserves
Definition
mostly found in the middle east, the US imports around 45% of the oil it uses and this number will increase
Term
formation of coal
Definition
many giant plants died in swamps, over time plants were buried over water and dirt, and eventually heat and pressure turn the plants into coal
Term
formation of oil and natural gas
Definition
in deep seas where millions of microorganisms die and settle into deeper cold water where they cannot be oxidized. As they become heated and buoyant and rise until they reach a trap rock where “black gold” forms. Natural gas always rises above oil bc its less dense
Term
gas hydrates
Definition
ice like solids that consist of gas molecules which are enclosed in the structure of water molecules
Term
obtaining coal
Definition
--Surface coal (less then 200 ft deep) mined by removal of topsoil and rock
--Underground coal – elevators to deep mine shafts where machines dig coal
Term
obtaining oil
Definition
drill wells pump oil to the surface, and then secondary recovery includes thermal, chemical, and fluid mixing, injection wells, and extraction wells
Term
Obtaining natural gas
Definition
found using seismic surveys, and obtained by drilling, then gas flows up through well and into pipelines easily
Term
source rock
Definition
where the fossil fuel is originally formed
Term
reservoir rock
Definition
rock that the fuel moves throught before reaching trap rock
Term
trap rock
Definition
oil traps often occur in anticlines or along a fault, the rock must be an aquiclude, impermeable to the flow of liquid and gas, like shale for example
Term
types of mines
Definition
deep mines, surface excavation (countour, area, mountain top, dredging, open pit)
Term
processing of ore
Definition
by gravity, leaching with cyanide, mercury, sulfuric acid, electromagnetic, and smelting
Term
waste produced
Definition
1 ton of copper leads to 110 tons of waste rock and 200 tons of earth moved, similar and larger numbers for other precious metals
Term
recycling
Definition
it takes 5% as much energy to produce aluminum from scrap metal as it does to process it from ore
Term
hydrologic cycle
Definition
Evaporation and transpiration -> condensation -> wind -> precipitation -> runoff -> Oceans and Lakes, also groundwater
Term
what drives the hydrologic cycle
Definition
Driven by the sun promoting evaporation and transpiration, which leads to humidity in the air and eventually rain
Term
humidity (saturation and relative)
Definition
--Saturation humidity – maximum amount of water an air mass can hold (increases with increasing temperature)
--Relative humidity – ratio of absolute humidity to saturation humidity
Term
dew point
Definition
when relative humidity reaches 100% excess water vapor condenses to liquid water, this is called the dew point
Term
vertical movement of air
Definition
flows from a higher to a lower pressure, which is upward in the atmosphere if it can overcome gravity. As hot air rises it expands due to lower pressure
Term
lightning
Definition
top of clouds net positive charge seeks to balance with bottom of clouds excess negative charge. Charge imbalance is partially induced by the downdrafts and updrafts opposite eachother
Term
thunderstorms
Definition
air temperature normally decreases upward from surface
--Rising warm, moist air may begin condensation, releasing latent heat and providing energy for severe weather
--Early stage requires a continuous supply of warm moist air
--Mature stage – precipitation begins when mass of ice crystals and water droplets too heavy for drafts to support. Falling rain causes down drafts, and the 2 opposing drafts together create winds, heavy rain, thunder, lightning, and hail
Term
why are thunderstorms common in southern and central US
Definition
warm moist air comes from gulf of mexico and is necessary for thunderstorms
Term
hail
Definition
comes from storms with buoyant hot air rising from the ground, upper level cold air creating large temperature contrasts, strong updrafts keeping hailstones aloft while layers are added
Term
microbursts
Definition
violent downdrafts of cold air during the mature stages of a thunderstorm, especially dangerous to airplanes
Term
tornado formation
Definition
air from gulf of Mexico (warm, humid), Canadian/Rocky Mountain (cold and dry), Jet stream winds (fast, high altitude) give thunderstorms shear
--Creates a corkscrew effect with warm air rising on one side and cool air falling on the other
--Rotation eventually develops with downward moving air in the center surrounded by upward spiraling funnel
Term
urban heat island
Definition
cities are up to 10 degrees C warmer then surrounding areas, warm air rising can create thunder clouds, and make cities more prone to tornadoes
Term
causes of global and regional climate change
Definition
--Change insolation, overall heat budget, global distribution of heat (oceanic circulation, continental distribution, location of mountain ranges)
Term
albedo
Definition
fraction of insolation reflected – Ice has high albedo, water has low albedo, land is intermediate depending on surface, high albedo = cool, so as icebergs melt in speeds up the heating of the planet
--Location of continents vs water effects climate change (in relation to equator)
Term
millenial oscillations
Definition
large millennial oscillations during the glacial period but not during interglaciation (at this scale)
--Greenland ice core and North-Atlantic marine sediment records correlate to orbital-scale changes slow cooling and then rapid warming
Term
D-O events
Definition
slow cooling followed by rapid warming
--25 of these during the last glaciations period
Term
Heinrich events
Definition
major episodes of ice rafting every 5,000 to 15,000 years, each rafting event followed by rapid warming
--Mess with the thermohaline conveyor, which is slowed down/shut off due to freshwater input=might trigger subsequent warming
--Come after D-O event
Term
sea level rise and associated problems
Definition
happens because the glaciers melt bc of global warming, and it is a problem because then the shorelines retreat
Term
extent of air pollution
Definition
local, regional, global effectsshould the EPA be enforced to limit CO2 emissions?
Term
role of inversion layer
Definition
--Cold air is heavy and under warm air cannot rise/is trapped; such cold air can be derived from the ocean of the mountains
--Warm layer acting like a cap leads to pollution
Term
bad versus good ozone
Definition
bad - photochemical smog; acts as a UV filter
good - high in the atmosphere
Term
greenhouse gases
Definition
Water vapor (greatest effect depending on humidity, only greenhouse gas not increasing), Carbon dioxide (largest contributor),Not very absorbent but is most important b/c of its volume and release into atmosphere through human activities,Methane, Nitrous oxide, Sulfur hexafluoride
Term
cause of seasonal cyclical change in CO2 levels
Definition
Seasonal variation of the growth of vegetation (boreal forests) from the Northern Hemisphere
--Atmospheric concentrations decrease starting in spring because respiration increases for trees
--Growth ceases starting in the fall through the spring=concentrations increase again
Term
CFC's and the Ozone hole
Definition
--Chlorofluorocarbons
--Once in the atmosphere, stay for a while
--Have enough time to rise to stratosphere and mesosphere and effect ozone layer
Term
flood recurrence interval
Definition
--Probability of a 100-year flood is 1%; 50-year flood is 2%
--Can construct flood-frequency curve by plotting flood discharge volumes vs. recurrence interval
Term
salt water incursion
Definition
occurs when overdraw freshwater on top of saltwater that is beneath=ruins well permanently
Term
glacial movement
Definition
upper flow is brittle, forms cracks and crevaces
lower flow is ductile, has folds and continuous flow
Term
drumlins
Definition
markings from movement of glaciers
Term
drumlins
Definition
markings from movement of glaciers
Term
swash and backwash
Definition
upper (swash) and lower (backwash) part of each wavefront
Term
wave cut benches
Definition
long, narrow strip of relatively level or gently inclined land that is bounded by distinctly steeper slopes above and below it
Term
atmospheric circulation
Definition
trying to reach equilibrium between temperatures
Term
coriolis effect
Definition
deflection of water or air because of earth’s rotation
--Arrows in above diagram indicate direction of the storms
--Earth’s rotation is fastest at the equator—rotation of the Earth causes angled movement of particles
Term
coastal upwelling
Definition
brings up nutrients
Term
El Nino
Definition
disruption/variation of the ocean-atmosphere system in the equatorial Pacific3 to 7 year cycle with weird Southern Surface Temperatures
--Southern oscillation=high and low pressures switch over Australia
--Easterly winds weaken, warm water sloshes east, Southern Surface Temps are higher off of Peru, no upwelling, rain/flooding in South America, drought in Australia, India, Indonesia
Term
La Nina
Definition
abnormally cold Southern Surface Temperatures
--Warm water further west than usual
--(compared to El Nino) usually stormier, cool SST in central Pacific, rain like normal conditions but sometimes stronger
Term
normal condition
Definition
winds push tropical waters west=warm Western Pacific and 0.5m higher sea level in Indonesia than Ecuador, cold water upwells in Eastern Pacific
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