lecture 3 cards Flashcards
Coriolis effect
Points at different latitudes on the earth’s surface rotatee at different velocities, currents in N. hemisphere move clockwise and in s. hemisphere move counterclockwise
Prevailing winds, north to south
Polar easterlies, westerlies, northeast trade winds, southeast trade winds, westerlies, polar easterlies
Air cells, from north to south
Polar cell, Ferrel cell, Hadley cell, Hadley cell, Ferrel cell, Polar cell
Eckman spiral
wind drives the surface water in a direction 45 degrees to the right of its path. Deeper waters continue to deflect to the right but move at a slower speed. **net water movement is at right angles to the wind direction
Low pressure system spirals
in Northern Hemisphere, cyclonic circulation around low pressure system, anticyclonic circulation around a high pressure system
Cyclonic
counter-clockwise
Anticyclonic
clockwise
Upwellings
Water moving vertically upwards under areas of low pressure. Brings nutrients to the surface, creates areas of high primary productivity.
Downwellings
Water moving vertically downwards under areas of high pressure. Restrict the supply of nutrients and cause areas of very low productivity.
Gyres
Large circular patterns of water movement because of coriolis effect, upwellings in the middle so there is water piled up in the center, gravity pulls the water downhill, creating a geostrophic current
Oligotrophic
Not much food available
Langmuir circulation
Small scales of circulation, mixes plankton organisms in the surface region, driven by the wind
Coastal upwellings
Upwellings along continental margins, on scales of 100s of kilometers
Ekman transport
Carries surface water away from continental margins, upwelled water replaces the water that moved away
Equatorial upwellings
created by the coriolis effect, drives water away from the equator and creates upwelling
Gulf Stream Eddies
large eddies formed by the gulf stream. North of the stream, eddies are warm and rotate clockwise, south they are cold and rotate counterclockwise
NADW
North Atlantic Deep Water, cold and salty, very dense, sinks and travels south
ABW
Antarctic Bottom Water, more dense than NADW, forces NADW to the surface
MOC
Meridional Overturning Circulation, thermohaline circulation or conveyor belt
Spring tides
When sun and moon are aligned, highest highs and lowest lows
Neap tides
When sun and moon are at 90 degree angles to each other, producing lower than average amplitudes of tides.
Semidiurnal tidal cycles
Twice per day
Diurnal tidal cycles
Typical, once per day
Mixed tidal cycles
Large land effect. One higher high water, a lower high water
Perihelion
When the earth is closest to the sun
Perigee
When the moon is closest to the earth
King tides
Occur when the moon and sun are aligned at the perigee and periholion
Fetch
Length of open ocean over which the wind blows
Crest
Highest point of the wave
Height
Vertical distance from crest to trough
Wavelength
Distance between crests
Period
Time it takes for a wave to go past a point
Capillary waves
Light winds over water causing ripples less than 1.74 cm in length
Gravity waves
Waves caused by wind greater than 4mph causing larger waves. Continue until water becomes shallow and they break in the surf
Tsunamis
Seismic sea waves, caused by seismic activity on the seafloor, earthquakes, landslides, volcanoes. Very long and very fast moving
ENSO
El Nino Southern Oscillation. Change in surface currents of southern oscillation over Pacific and Indian oceans
La Nina
Opposite extreme of El Nino
Divisions of the marine environment
Pelagic, benthic, neritic, oceanic
Pelagic
Open ocean environment
Benthic
Ocean bottom environment
Neritic
From the shore out to 200m depth
Oceanic
Area beyond the 200m contour
Mesopelagic zone
Middle of the pelagic, oxygen minimum caused by decomposition. O2 minimum zone has expanded over the years because of global warming
Plankton
Organisms that drift with ocean currents, classed by size
Nekton
Organisms that move independently of currents
Benthos
Organisms that live on or in bottom sediments
Epifauna
Benthic organisms that live on the bottom sediments
Infauna
Benthic organisms that live in the bottom sediments
Classification of common dolphin
Metazoa, chordata, mammalia, odontocete, delphinidae, Delphinus delphis
Classification of giant kelp
Protista, Phaoephyta, Phaeophycae, Laminariales, Lessoniaceae, Macrocystis pyrifera
