Marine Biology Dr. McKay
During the Northern Hemisphere's summer solstice, the sun stands above
23½°N.
The Tropic of Capricorn is at ____ latitude.
23½°S
How long does it take for the Earth to make one rotation on its axis?
24 hours
The westerlies lie between which latitudes?
30 degrees and 60°N and S
On December 15th, which of the following locations will receive the highest value of solar radiation?
30°S
Earth's age is estimated at ____ years.
4.6 × 10^9
Light and sound are _______ by seawater.
All of these are correct.
Manganese nodule mining has not developed because of
All of these are correct.
Which ocean basin is the largest?
Pacific
Approximately what percentage of incoming solar radiation is absorbed by the surface of the Earth?
47%
The maximum penetration of visible light in clear seawater is about ______ meters.
1000
What percent of a parent radioactive element would remain after three half-lives of decay to its daughter isotope?
12.5
A time zone is approximately ____ degrees wide.
15
The density of the inner core reaches a maximum of about ____ grams/cm3.
16
The mean surface temperature of Earth is about
16°C.
During the next magnetic reversal, the magnetic force field surrounding Earth will shift by about
180°.
The present oceans have been created during the last
225 million years.
Fresh water has its maximum density at
4°C.
Major deposits of silicous oozes from the radiolaria are found centered on which latitudes?
5°N
One fathom is equal to
6 feet and roughly 2 meters.
A parcel of air from the South Pole moves due north along the prime meridian; its motion is independent of Earth's rotation. Over what longitude will it be found four hours later?
60°W
The International Hydrographic Organization defined the northern boundary of the Southern Ocean to be
60⁰S.
What is the approximate length of the mid ocean ridge system that extends around the globe through all of the major ocean basins?
65,000km
Approximately what percentage of gas emitted by volcanoes is water vapor?
70%
If the salinity of ocean water is 36‰, there are ______g of salt left from evaporating 2kg of seawater.
72
Which circle of latitude or longitude has the smallest circumference?
80°S
Which of the following are found along subduction zones?
All of these are correct
Earth's surface is protected from extreme temperature change and water loss by
All of these are correct.
Eddies
All of these are correct.
Heat energy gained at low latitudes is redistributed to higher latitudes by
All of these are correct.
In areas of downwelling, there is not likely to be a near-surface
All of these are correct.
Sea surface color observed by satellite instruments is affected by
All of these are correct.
The coldest, deepest, densest water in the oceans
All of these are correct.
The trailing margin of a continental landmass ______ than its leading margin.
All of these are correct.
Which of the following occurred during the Paleozoic era?
All of these are correct.
Which of the following chemicals is commercially extracted from seawater?
Bromine
The current at the eastern boundary of the Sargasso Sea is the ______ Current.
Canary
Which gas has the highest concentration throughout the entire ocean?
Carbon dioxide
Which substance has the greatest density?
Cold salt water
Which method best transmits heat through water?
Convection
Which of the Earth's layers has the greatest density?
Core
Which of the following is least likely to be a major component of marine sediments?
Cosmogenous materials
Which of the following is NOT true about the influence of Ekman Transport on surface currents?
Each subsequent layer of water moves more quickly than the one above it.
Sources of the oceans' salts are believed to include
Earth's crust, Earth's early atmosphere, and volcanic eruptions
Which of the following help us believe that Earth's mass is distributed spherically and uniformly around Earth's center?
Earth's spherical shape and lack of rotational wobble
The low pressure area near the equator is known as the
Intertropical Convergence Zone.
Which ion has the shortest residence time in the oceans?
Iron
Which statement(s) about El Niño is(are) true?
It produces warm surface water along the Peru-Ecuador coast, it interrupts the southeast tradewinds and displaces the doldrums, and it is associated with a displacement of the jet stream
Which current flows north to south along the northeast coast of the United States?
Labrador
When talking about plate tectonics, which of the Earth's layers comprises the plates?
Lithosphere
The first scientific voyage to use an echo sounder on a large scale was the
Meteor expedition.
The North Atlantic prevailing westerlies drive the
North Atlantic and West Wind Drift.
The Arctic Ocean receives
North Atlantic water from the Norwegian current and North Pacific water through the Bering Strait
Which layer is believed to behave most like a liquid?
Outer Core
Which ocean basin is the deepest on average?
Pacific
Which desalination process requires the least energy?
Reverse osmosis
Which method is being used to investigate the structure of the mantle?
Seismic tomography
Which of the following is NOT an example of a hydrogenous sediment?
Tektites
Why are meteorites used to establish an age for the Earth?
They are believed to be the same material from which Earth formed and rocks on Earth have been recycled since the Earth was formed and are not believed to be as old as the Earth itself
At what latitude is the sun directly overhead on the June Solstice?
Tropic of Cancer
Which latitudinal area tends to have the highest average surface salinity?
Tropics (25o-30o)
Which phase change reaction requires the most energy?
Vaporization
Which of the following materials has the highest specific heat?
Water
Throughout time, continents break apart and collide and ocean basins open and close. This cyclical process is known as the
Wilson cycle.
The long red wavelengths of visible light are
absorbed in the first meter.
The floor of a major ocean basin is called a(n)
abyssal plain.
The effect of ozone destruction is most severe
at polar latitudes.
The dissolving ability of water is related to
attraction between the water molecule's positive and negative charges and charges on other atoms.
The motion between the two sides of a transform fault is greatest
between the adjacent ridge axes.
The pH of seawater is regulated by
carbon dioxide
The total change in concentration of carbon dioxide with depth is small because
carbon dioxide combines with water to form carbonic acid and bicarbonate
The depth at which the rate of photosynthesis balances the rate of plant respiration is known as the
compensation depth.
Salinity may be measured by checking the water's
conductivity
Water heated from below distributes the added heat by _____, whereas the still surface of water heated from above distributes the added heat by ______
convection; diffusion and conduction
Volcanic activity occurs at all of the following except
convergent boundaries between two continental plates.
The polarity of water molecules is responsible for all of the following, EXCEPT
covalent bonding.
A fathom is a unit of
depth.
The silica rich oozes of the Pacific Ocean are due to _______ at high latitudes and ______ at low latitudes.
diatoms, radiolarians
Nutrients are non-conservative constituents of seawater because they
do not maintain constant ratios to each other and are recycled into plants and animals.
The single most important source of deep water to all of the world's oceans is
downwelling in the North Atlantic.
Currents are less intense on the ______ side of the North Pacific and North Atlantic oceans.
east
Electrodialysis produces ________ from low-salinity seawater.
fresh water
A great circle can be described as
having its center at Earth's center and being the shortest path between two points on Earth's surface.
Seawater taken from an area with a large, growing plant population has a
high O2 and low nutrient content.
El Niño events are associated with
high pressure in the eastern Pacific.
If ocean water were incompressible, sea level would be _____ its present level.
higher than
What type of material is thought to explain the larger size of the outer planets relative to the inner planets?
ice
The addition of salt to fresh water to form salt water
increases the density of the water.
The east coast of South America
is a passive continental margin and has a relatively wide continental shelf.
The Equatorial Counter current
lies between the North and South Equatorial currents.
A Secchi disk is used to measure the attenuation of
light.
The crust and the mantle are divided into the following layers in order of increasing depth:
lithosphere, asthenosphere, mesosphere
A storm tide is due to the
low atmospheric pressure at a storm's center and strong winds creating a surface flow toward the shore.
In the middle latitudes of the Northern Hemisphere, a _____ pressure cell develops over the ocean in winter and a ____ pressure cell develops in summer
low; high
Hurricanes derive their energy from _______ pressure zones in the ______ latitudes.
low; tropical
A doppler current meter shows an increase in sound frequency if the water flow is
moving toward the meter.
Higher seafloor heat flow values are found
near ocean ridge systems.
Deep-ocean water in the Atlantic Ocean flows mainly
north-south
A south wind produces a _____ surface current in the Northern Hemisphere.
northeast
Prevailing ________ winds are needed to provide the net movement of surface water seaward along the west coast of North America.
northerly
A local shore wind controlled only by daily temperature variation between land and water will blow _____ during the night.
offshore
Along the west coast of India, the prevailing wind during the winter blows ______ and produces the _______.
offshore; dry monsoon
The oceans' oldest sediments are found
on top of the basalt layer, far from spreading centers.
Wind-driven surface currents move at a speed that is ________ the average driving wind speed.
one one-hundredth
During the Indian wet monsoon, the prevailing winds blow ____ in the _____
onshore; summer
The area north of 66½°N is in darkness when the sun is directly
over 23½°S.
Manganese nodules are
pelagic hydrogenous sediment.
The winds that begin the polar high pressure zones are called
polar easterlies.
Covalent bonds link a water molecule's
positively charged hydrogen atoms and negatively charged oxygen atom.
The sediments of the central deep-ocean basins of the North Pacific are formed chiefly from
red clay particles.
Side scan sonar images are the product of the
reflectivity of the material, depth of the water, and angle at which the sound strikes the object.
Carbon dioxide is added to seawater by
respiration, decomposition and transfer from the atmosphere.
Thinning of Earth's crust and the resulting faulting is called
rifting.
The coriolis effect deflects objects in the Northern Hemisphere to the _________ relative to their direction of motion.
right
Submarine canyons are associated with
river systems and turbidity currents.
Density of seawater increases as
salinity and pressure increase and temperature decreases.
Electrical conductivity readings at a known temperature measure
salinity.
The seabed is presently being mined in the U.S. for
sand and gravel.
The continental rise is a product of
sedimentation.
Carbon dioxide in seawater keeps the water's pH
slightly alkaline.
A current meter measures water
speed and direction.
Magnetic stripes on the seafloor are created at
spreading centers.
Atmospheric pressure is greatest in the
stratosphere.
The process of changing ice directly to water vapor is known as
sublimation.
Turbidity currents produce some
submarine canyons.
The rate at which the oceans absorb carbon dioxide is controlled by
temperature, salinity and pressure, pH, and mixing and circulation processes
Close to shore on the continental shelf at high-temperate latitudes, _______ deposits are most likely to predominate.
terrigenous
The maximum actual solar radiation that reaches Earth's surface is slightly less than the solar constant because
the atmosphere absorbs some energy and the atmosphere reflects some energy.
Sources of oxygen in the open sea include
the atmosphere and photosynthesis.
Above a salt content of 24.7 g/kg, as temperature decreases
the attenuation factor of light increases.
Red clay obtains its characteristic color from
the oxidation of iron.
The annual range of surface temperature is greater on land than at sea because
the specific heat of water is greater than that of land
A rapid change in temperature with depth is called a
thermocline.
Earth is the ____ planet from the sun
third
A sediment deposit close to the continental rise having a coarse material overlaid by successively finer materials of nonmarine origin is called a
turbidite.
An area drawn on a hypsographic curve equates to a(n)
volume of land or water
Above a salt content of 24.7 g/kg, as temperature decreases
water density increases to the freezing point and the freezing temperature decreases as salt content increases.
The Gulf Stream forms eddies, or rings, with cold water cores at the _______ edge of the Gulf Stream current.
western
The surface tension of pure water will increase
when salt is added and if the temperature decreases
The thermocline found in water above 500m at temperate latitudes disappears and the water column becomes neutral in
winter.
