Chapters 4- 8 Exam Questions
Sigma - t is the oceanographer's short hand for the density of seawater. It is defined as (density -1.0) x 10^3. If the density of seawater is 1.02825 g/cm^3, the sigma t value is a. 0.2925 b. 29.25 c. 0.02529 d. 25.29
29.25
Trade Winds
30 N- 30S; towards equator to the west (Northeasterlies and southeasterlies)
On December 15th, which of the following locations will receive the highest value of solar radiation? a. 30 N b. 0 c. 60 N d. 30 S e. 60 S
30 ˚S
Westerlies
30- 60 N/S; blow to the east away from equator
If a surface water wave has a wavelength of 200m and a 5 second period, its speed is a. 100m/ sec b. 10m/ sec c. 400 cm/sec d. 4000 cm/ sec e. 40 cm/ sec
4000 cm/sec (use C= L/T)
How many calories must be removed from 5g of pure water at 10˚C to convert water to ice? a. 20 b. 8000 c. 450 d. 1200 e. 80
450
If a sound pulse is sent vertically downward into the sea and its reflected echo from the seafloor returns 6 seconds later, the depth of the water is __________ meters (the average speed of sound in seawater is 1500m/sec). a. 3000 b. 12,000 c. 9000 d. 6000 e. 4500
4500
What causes high and low pressure?
uneven heating
The orbital motion of deep water wave extends to a depth equal to a. one half the wavelength b. one half the wave's height c. twice the wavelength d. the seafloor depth e. the wave's height
1/2 the wavelength
A water wave reaches an unstable breaking point when the steepness ratio, H/L, reaches a. 1:2 b. 1:7 c. 1:5 d. 1:10 e. 1:8
1:7
Polar Easterlies
60-90 N/S; blow to the west towards equator
The average movement of all water affected by the wind is __________ degrees to the _________ of the wind motion in the southern hemisphere a. 45; right b. 180; no direction c. 90; right d. 90; right e. 45; left
90˚; left
Shallow water speed formula
C= (gD)^(1/2)
Deep water speed formula
C= L/T
The pH of seawater is regulated by a. oxygen b. pressure c. temperature d. CO2
Carbon Dioxide
Low Productivity
Convergence- downwelling
What causes windbands?
Coriolis Effect
High productivity
Divergence - upwelling
The highly productive seas along the equator are the result of the tropical convergence located here (T or F)
False
Downwelling is produced by diverging surface currents (T or F)
False (convergent)
When waves arrive at monitoring stations set up long distances from the storm center, which waves arrive first? a. long period waves b. capillary waves c. steeper waves d. internal waves e. short- period waves
Long period waves
A storm tide is due to the a. low atmospheric pressure at a storm's center b. strong offshore winds c. low atmospheric pressure at a storm's center and strong winds creating a surface flow toward the shore d. strong winds creating surface flow toward the shore e. all
Low atmospheric pressure at a storm's center and strong winds creating a surface flow toward the shore
North Pacific Gyre Currents
North Pacific, California, North Equatorial, Kuroshio
During the Indian wet monsoon, the prevailing winds blow __________ in the ____________. a. onshore; summer b. onshore; summer and winter c. onshore; winter d. offshore; winter e. offshore; summer
Onshore; summer
Which processes cause the surface seawater to increase in density? a. sea ice melting and surface water evaporations b. sea ice melting c. sea ice formation and surface water evaporation d. sea ice formation e. surface water evaporation
Sea ice formation and surface water evaporation
South Atlantic Gyre Currents
South Equatorial, Benguela Current, Brazil Current, (Antarctic Circumpolar?) - counterclockwise
South Pacific Gyre Currents
South Equatorial, Easy Australian, Antarctic Circumpolar, Peru- counterclockwise
Which latitudinal area tends to have the highest average surface salinity? a. Tropics (25˚- 30˚) b. Midlatitudes (60) c. Polar areas (80-90) d. equatorial areas (0-10) e. none
Tropics (25˚- 30˚)
Antarctic bottom water has a very narrow range of both salinity and temperature; this water is nearly homogenous (T or F)
True
Upwelling occurs along the coast of California when winds blow from the North (T or F)
True
Usually temperature, salinity, and pressure distributions cause ocean water density to increase with depth (T or F)
True
Which phase change reaction requires the most energy? a. cooling b. freezing c. each requires the same amount of energy d. melting d. vaporization
Vaporization (540 cal/g)
Changes in water density in the oceans create a. the sofar channel b. light refraction c. sound shadows d. all e. non
all
Clouds___________ radiation. a. radiate longwave b. intercept longwave c. reflect shortwave d. absorb shortwave e. all
all of these
The coldest, deepest, densest water in the oceans a. is Antarctic bottom water b. is formed around Antarctica c. flows north d. All e. none
all of these
The arrangement of the hydrogen and oxygen atoms in a water molecule causes the water molecule to a. lose heat rapidly b. slide past other water molecules c. be polar d. have a lattice arrangement in the gaseous state e. orient in only one direction
be polar
The _________ wavelengths of light penetrate deepest into the ocean a. blue b. black c. ultraviolet d. infrared e. red
blue
Water heated from below distributes the added heat by __________, whereas the still of surface of water heated from above distributes the added heat by ________ a. conduction; convection b. convection; diffusion and conduction c. conduction; diffusion d. diffusion; diffusion e. diffusion; convection
convection; diffusion and conduction
Langmuir Cells
convergent and divergent zones - bring plankton to surface
Thermohaline circulation is driven by changes in a. convection b. surface tension c. pressure d. viscosity e. density
density (temperature and salinity)
The restoring force of a fully developed wind wave is a. density b. solar heat c. surface tension d. gravity e. viscosity
gravity
North Atlantic Gyre Currents
gulf stream (S--> N); North Atlantic current (W--> E); Canary Current (N--> S); North Equatorial current (E--> W)
The average energy of a wave is related to the square of its a. wavelength b. period c. height d. speed e. all
height (E^2 = 1/8 p g H)
A water type having both high salinity and warm temperature but dense enough to be found at about 1000m in the central North Atlantic has been formed a. Near Greenland b. in the equatorial regions c. in the Mediterranean sea d. in the Red Sea e. in the Caribbean Sea
in the Mediterranean Sea
Waves occurring at the interface between layers of seawater and fresh water are called a. density waves b. interference waves c. surface waves d. internal waves e. freshwater waves
intertidal waves
Sofar Channels
is a horizontal layer of water in the ocean at which depth the speed of sound is at its minimum - depth is approximately 1000m
Hurricanes derive their energy from ________ pressure zones in the ___________ latitudes a. high; mid b. high; tropical c. low; mid d. low; tropical e. none
low; tropical
Trace elements in seawater are a. significant component of the total salt content of sea water b. toxic to marine life forms c. in higher concentrations at lower salinities d. necessary for many marine life forms e. found in concentrations suitable for commercial use
necessary for many marine life forms
A local shore wind controlled only by daily temperature variation between land and water will blow __________ during the night a. onshore b. parallel to the shore c. 45 degrees to the left d. 45 degrees to the right e. offshore
offshore
The refraction of waves tends to concentrate wave energy ___________ and disperse energy __________ a. along coasts; behind breakwaters b. on headlands; in bays c. along coasts; in bays d. in bays; on headlands e. along coasts; on headlands
on headlands; in bays
The concentration of carbon dioxide in surface water is low, whereas the concentration of oxygen is high because of the a. conversion of carbon dioxide to bicarbonate b. exchange of gases between the atmosphere and the ocean c. respiration of plants and animals d. photosynthetic processes e. difference in solubility of the gases
photosynthesis process
The Coriolis effect deflects objects in the Northern Hemisphere to the _________ relative to their direction of motion a. west b. right c. east d. north e. left
right
Water transported shoreward in the surf zone is returned seaward by a. rip currents b. reflected waves c. refracted waves d. internal waves e. shallow water waves
rip currents
The Coriolis effect arises primarily from the a. rotation of the earth around the sun b. curvature of the Earth's surface c. motion of the oceans in their basin d. rotation of Earth around its axis e. effect of the winds high in the atmosphere
rotation of Earth around its axis
Extreme variation in the ocean's temperature is prevented by seawater's a. viscosity b. density c. compressibility d. transparency e. specific heat
specific heat
Layering in the ocean occurs because a. surface processes form water layers of differing combination of salinity and temperature b.surface processes form water layers of differing combination of salinity and temperature and atmospheric processes control conditions at the surface c. processes at depth add and subtract salt and heat d. atmospheric processes control conditions at the surface e. all
surface processes form water layers of differing combination of salinity and temperature and atmospheric processes control conditions at the surface
If extremely cold fresh water is aded on top of seawater a. the cold water will sink and move rapidly out of the area b. an overturn will begin immediately c. the wind will control the surface mixing d. the cold water will float at the surface e. the cold water will sink to the bottom and stagnate
the cold water will float at the surface
The speed of shallow water wave varies with a. its period b. its steepness c. its height d. its depth of the water e. its amplitude
the depth of the water
A rapid change in temperature with depth is called a a. midwater current b. halocline c. thermocline d. pycnocline e. photic level
thermocline
In a closed basin, a single- node standing wave oscillation tends to have a wavelength that is _______ the basin length a. twice b. the same as c. four times d. one quarter e. one half
twice
The speed of deep water wave varies with
wavelength
Wave height of wind waves depends on a. windspeed and duration b. windspeed and duration and fetch c. wavelength d. wavelength and windspeed and duration e. fetch
windspeed and duration and fetch
The thermocline found in water above 500m at temperate latitudes disappears and the water column becomes neutral in a. fall b. winter c. spring d. summer e. none
winter