1
Q
Define proton, neutron, electron, and nucleus
A
Atoms are composed of:
– Nucleus – the center of the atom consisting of:
*Protons - positively charged particles
*Neutrons - neutrally charged particles
– Electrons – negatively charged particles that orbit the nucleus in discrete electron shells.
2
Q
Define atoms
A
the smallest unit that displays all the
properties of the material.
3
Q
Define ion and describe the difference between a cation and an anion.
A
Ions are atoms with either more or fewer
electrons than protons
-Ions are electrically charged
-Cations are positively charged ions while anions are negatively charged ions
4
Q
Define isotope and describe how it’s different from an ion
A
- Isotopes are atoms containing the same number of protons, but different numbers of neutrons.
– Therefore, they have different atomic weights
Ions are charged atoms that result from the loss or gain of electrons, while isotopes are variations of the same element that differ in the number of neutrons.
5
Q
Define molecule and identify what type of bonds they form
A
Molecules are chemically combined compounds formed by two or more atoms.
They form covalent bonds.
6
Q
Define organic and inorganic molecules. Be sure to give an example of each.
A
Organic molecules have chains of carbon atoms covalently bound to other carbon and hydrogen atoms.
-EX. Glucose (C6 H12 O6)
Carbon atoms in inorganic molecules are not covalently bound to other carbon or hydrogen atoms.
-EX. Carbon Dioxide (CO2)
7
Q
At the atomic scale, kinetic energy can be referred to as ____________ . Kinetic energy is the energy of ______________.
A
-Heat energy
-Motion
8
Q
Describe what happens on an atomic scale when heat is applied to a solid, liquid, and a gas.
A
- In solids, atoms or molecules:
– Vibrate weakly
– Are rigidly held in place - In liquids, atoms or molecules:
– Vibrate more rapidly
– Move farther apart
– Are free to move relative to each other - In gases, atoms or molecules:
– Are highly energetic
– Move far apart
– Are largely independent
9
Q
Define melting, freezing, evaporation, and condensation
A
-melting: the transition from solid to liquid
-Freezing: the transition from liquid to solid
-Evaporation: the transition from liquid to gas
-Condensation: the transition from gas to liquid
10
Q
What factor controls the density of freshwater?
A
- Temperature
– As temperature increases:
*Atoms or molecules move farther apart
*Density (mass/volume) decreases,
because there is less mass (fewer
atoms) in the same volume
11
Q
What are the four attributes water has due to its hydrogen bonding? Explain each
A
- H2O is sticky (i.e., adhesion & cohesion)
- H2O can absorb a lot of energy (i.e., heat capacity)
- H2O has a large liquid range (freezing at 0 degrees C; boiling at 100 degrees C)
- H2O as a solid is less dense than as a liquid (i.e., ice floats!)
12
Q
Explain why ice floats (be specific and use terminology discussed in class)
A
- Ice floats in water because all of the molecules in ice are held in hexagons.
– The center of the hexagon is open space, making ice 8% less dense than water.
– Liquid water can have many hydrogen bonds (depending on the temperature), making it denser than ice, especially
at lower temperatures. - Because of the open-crystal structure of solid water, ice is less dense than liquid water.
13
Q
Why is water considered to be a universal solvent?
A
- The asymmetry of a water molecule and distribution of electrons result in a dipole
structure.
– The oxygen end of the molecule is negatively charged.
– The hydrogen end of the molecule positively charged.
14
Q
Define salinity and identify the units used to measure it. What is the average salinity of seawater?
A
- Salinity is the total amount of salts dissolved in the water.
– It is measured in parts of salt per thousand
parts of salt water and is expressed as ppt
(parts per thousand) or abbreviated as o/oo. - Average salinity of the ocean is about 35 o/oo.
15
Q
Identify the salt ions that primarily make up 99% of seawater. Explain why they are a conservative property.
A
-Sodium (Na+)
– Chloride (Cl–)
– Sulfate (SO4–2)
– Magnesium (Mg+2)
– Calcium (Ca+2)
– Potassium (K+)
Because the major chemical constituents of seawater display little variation over time
16
Q
Identify the major nutrients found in seawater. Explain why they are a nonconservative property.
A
– Nitrogen
– Phosphorus
– Silicon
Because Concentration of nutrients vary greatly over time
17
Q
Identify the three major gases found in seawater. Which is most abundant?
A
In order of decreasing abundance, the major gases in the sea are:
– Nitrogen
– Oxygen
– Carbon dioxide
18
Q
Explain why salinity of the ocean is in a steady state condition. Where are most of the salt ions coming
from? What removes salt ions from the seawater?
A
- Salinity in the ocean is in a steady-state condition
*This is because the amount of salt added to the ocean (input from source) equals the amount removed (output into sinks).
- Rivers dissolve salts from the earth and are the main source of salt ions to the ocean
- Sea spray from waves removes ions from the ocean and deposits a film of salts on the land.
19
Q
What factors control the density of air
A
– Temperature
– Pressure
– Moisture content
20
Q
Define wind. How are winds named?
A
- Movement of air across a pressure gradient parallel to
Earth’s surface is called a wind. - Winds are named for the direction from which they come
21
Q
What factor determines the pattern of global winds?
A
Global winds blow in response to variation in pressure related to uneven solar heating (insolation) of Earth’s surface
22
Q
Describe Coriolis deflection.
A
the apparent deviation of objects
moving across Earth’s surface
– Objects are deflected to the right of the direction of travel in the Northern Hemisphere.
– Objects are deflected to the left of the direction of travel in the Southern Hemisphere.
23
Q
Because of the Coriolis Effect, identify the three major convection cells, where they are located and identify the winds they produce.
A
- The Hadley cell extends from the equator to about 30˚ latitude. Produce the westerlies
- The Ferrel Cell extends from 30˚ to about 50˚ latitude. Produce the easterlies
- The Polar Cell extends from 90˚ to about 50˚ latitude. Produce trade winds
24
Q
How are wind-driven currents produced?
A
Wind-driven Currents Are Produced by the
Interaction Between the Wind and the Water
* As wind moves across the water, air molecules collide with water molecules.
* When they collide, energy is transferred from the air to the water.
* This energy transfer is inefficient:
– Water moves at about 3%–4% of the wind
speed.
25
Define gyre and explain what it is caused by.
* A gyre is a circular current caused by:
– Westerly driven ocean currents in the trade winds
– Easterly driven ocean currents in the westerly wind belts
– Coriolis effect (Eckman Flow) on the moving water
– Deflection of the ocean currents by the continents
26
What direction do gyres in the Northern Hemisphere circulate? Southern Hemisphere?
Northern Hemisphere- clockwise
Southern Hemisphere- counterclockwise
27
Explain how mounds and depressions form on the sea surface
* Mounds on the ocean’s surface are caused by converging currents.
* Depressions on the ocean’s surface are caused by diverging currents.
28
Define Wave period
The time it takes to complete one wave cycle
29
Identify the 6 classes of waves based on wave period
–Capillary Waves
-Chop
– Swell
– Seiches
– Tsunamis
– Tides
30
What factors control the size and type of wind-generated waves?
– Wind velocity
– Wind duration
– Fetch - distance over which the wind blows
– Original state of the sea surface
31
What happens to the wavelength, period, and height of a wave as wind velocity increases?
All increase, but only if wind duration and fetch are sufficient
32
Define fetch and a fully developed sea.
-Uninterrupted distance over which the wind blows without significant change in direction.
- A fully developed sea means the wind-generated waves are as large as they can be under current wind velocity and fetch conditions.
33
Define significant wave height. What is it a good indicator for?
Significant wave height is the average of the highest one-third of the waves present.
– It is a good indicator of potential for:
* Wave damage to ships
* Erosion of shorelines
34
Define and describe progressive waves.
* Progressive Waves – waves that travel across the sea surface
* As waves pass across a surface, wave forms and wave energy move rapidly
forward, but not the material (water, in this case) through which the wave is moving.
* The material moves very little or not at all.
35
Identify the two types of ocean wave motion. What happens to the diameter of the orbit when wave size increases? When depth below the surface increases
1) Forward motion of the wave form
2) Orbital motion of water molecules & particles as the wave passes.
– The sum of all motions experienced by the molecule is ~0, so there is no net motion of the water particles.
– Diameter of orbit:
* Increases with increasing wave size
* Decreases with depth below the water surface
36
Describe Stoke’s Drift and its significance
Stoke’s Drift - a net displacement of water, which is insignificant compared to
the speed of a wave in deep water, but significant in shallow water where it causes
nearshore currents
37
Define wave base and describe what happens when water is deeper than the wave base. Shallower than the wave base?
* Wave base - the depth to which energy related to a surface wave can be measured (below this depth, there is no orbital motion of water molecules), about ~1/2 the wavelength
* If the water is deeper than wave base:
– Orbits are circular
– There is no interaction between the seabed and the wave
* If the water is shallower than wave base:
– Orbits are elliptical
– Orbits become increasingly flattened toward the bottom
38
Identify and describe the three types of waves defined by water depth.
– Deep-water wave – a wave moving through water deeper than its wave-base (1/2 wavelength), so bottom interactions are absent
– Intermediate-water wave – wave moving through water ½-1/20th the wavelength)
– Shallow-water wave – wave moving through water less than 1/20th the wavelength
39
Define celerity and explain how to calculate it. What units are used to measure celerity?
* Celerity - the velocity of the wave form, not of the water (speed is used for mass, which celerity is not concerned with)
* Celerity = wavelength/period
* The celerity of a group of waves all traveling at the same speed in the same direction is less than the speed of individual waves within the group
Units are distance per time
40
Identify and describe the three types of waves based on wave interference.
* Chaotic seas – The chaotic patterns of
seas are produced by waves of many sizes
interfering with one another.
* Ocean swells – A regular ocean swell is
produced by dispersion that separates waves on the basis of their celerity
* Breakers – Breakers dissipate their
energy at the shoreline by wave collapse.
41
Define wave interference, constructive wave interference, destructive wave interference, and complex wave interference
* Wave interference - the momentary interaction between waves as they pass through each other
* Constructive wave interference- deepens the wave troughs and raises the wave crests, producing a larger wave.
* Destructive wave interference-reduces the height of the larger wave.
* Complex Wave Interference- both construction and destructive wave interference occur simultaneously
42
Near shore, wave height ____________ , as wave length ____________.
increases
descreases
43
What happens to wave speed, wavelength, and wave height when water depth decreases (becomes shallower).
– Wave speed decreases
– Wavelength decreases
– Wave height increases
44
Define refraction
the bending of a wave crest into an
area where it travels more slowly.
45
Identify and describe the three types of breakers.
* Spilling breaker - the crest of the wave becomes over steepened, breaks, and cascades down the front of the wave as it proceeds through the surf zone.
* Plunging breaker – the crest curls over the front of the advancing wave and evolves into the classic “pipeline” shape
* Surging breaker – the wave does not break, because it never attains a critical wave steepness.
45
How do you calculate wave steepness? What happens to wave steepness in shallow water? When will the wave become unstable and break?
* Wave steepness =
wave height /wavelength
* In shallow water:
– Wave height increases
– Wavelength decreases
* When H/L ≥ 1/7, the wave becomes unstable and breaks.
46
Define and describe storm surge and explain how storms affect the shores.
*Storm surge – sudden changes in coastal water levels due to storms
*The deeper water is at the shore, the farther waves can progress inland.
*Storm surge is especially severe when it occurs during a spring high tide.
*Storms affect the shore in two main ways:
– Water surface rises due to low atmospheric pressure
– Strong onshore winds drive water shoreward
47
Define internal wave. Where are they found? How are they different from surface waves?
* Any disturbance to the pycnocline can generate internal waves, including:
– Flow of water related to the tides
– Flow of water masses past each other
– Storms
– Submarine landslides
Internal Waves Form Within the Water Column Along the Pycnocline
* There is small density difference between the water masses above and below the pycnocline.
– Therefore, properties of internal waves are different from
surface waves.
* They travel more slowly.
* They can be much larger.
48
What disturbances can generate internal waves?
* Any disturbance to the pycnocline can generate internal waves, including:
– Flow of water related to the tides
– Flow of water masses past each other
– Storms
– Submarine landslides
49
Define and describe tsunami. Where do they originate from?
* Tsunamis were previously called tidal waves but are unrelated to tides.
* Tsunamis consist of a series of long-period waves characterized by:
– Very long wavelength (up to 100 km)
– High speed (up to 760 km/hr) in the deep ocean
* Because of their large wavelength, tsunamis are shallow-water waves as they travel across the ocean
basin.
* They only become a danger when reaching coastal
areas where wave height can reach 10 m or more.
Originate from earthquakes in the ocean basin
50
Define tides and explain what they are caused by.
* Tides – periodic raising and lowering of ocean sea level
– Occurs daily
* Tides have a wave form.
* They differ from other waves, because they are caused by the interactions between the ocean, Sun, and Moon.
51
Explain how to calculate tidal range.
You subtract the low tide level from the high tide level.
Tidal range= High tide level- low tide level
52
Define and describe spring tides.
– Earth, Moon, and Sun are aligned in a straight line
– The tidal bulges display constructive interference, producing high high tides and low low tides
* Spring tides coincide with the new and full Moon.
53
Define and describe neap tides.
– Earth, Moon, and Sun are aligned forming a right angle
– Tidal bulges display destructive interference, producing low high tides and high low tides
* Neap tides coincide with the first and last quarter Moon.
54
Due to both the Earth and Moon revolving eastward, what happens to the timing of tides?
This causes the tides to occur 50 minutes later each day.
55
Identify and describe the three basic types of daily tides defined by their period and regularity.
– Diurnal tides - one high and one low each day
– Semidiurnal tides – two high and two low each day
– Mixed tides – high and lows of unequal shape twice daily
56
Define tidal period. The crest and troughs of the wave represent what types of tides (high/low)?
* Tidal period is the time between consecutive high or low tides varies between 12 hours 25 minutes and 24 hours 50 minutes.
* The crest of the wave form is high tide
* The trough is low tide
57
Explain how to calculate gravitational force. What happens to gravitational force if you increase mass or decrease distance between the two objects?
F = G (M1*M2)/r^2
G: gravitational constant
M1: mass 1
M2: mass 2
F: force of gravity
r: distance between M1 and M2
gravitational force increases
58
Where can we feel the greatest gravitational force from the moon? Least?
* Greatest force at zenith – closest to moon
* Least force at nadir – furthest from moon and opposite zenith
59
Define centripetal force and resultant force. What happens due to resultant force?
* Centripetal Force -a force that acts on a body moving in a circular path and is directed toward the center around which the body is moving
* Resultant force - the single force and associated torque obtained by combining a system of forces and torques acting on a rigid body
due to resultant force--- torque
60
Explain tidal bulges. Which creates larger tidal bulges, sun or moon? Why?
Gravitational attraction and centrifugal force produce two tidal bulges of
water of about the same size, positioned on opposite sides of the Earth.
The moon creates larger tidal bulges because it is much closer to each and has a stronger gravitational force.
61
Define flood tide and ebb tide.
* Flood tide – water moves toward shore
* Ebb tide – water moves away from shore
62
According to the dynamic model of tides, the movement of tides across ocean basins is based on what two factors?
* In the dynamic model of tides, movement of tides across ocean basins is:
– Deflected by the Coriolis effect
– Blocked by continental landmasses
63
Describe rotary wave and amphidromic systems.
– Each day, it completes:
* Two cycles around the basin, if the tide is
semidiurnal
* One cycle around the basin, if the tide is diurnal
* A rotary wave is part of an amphidromic system
(rotary standing wave).
64
Describe cotidal lines and co-range circles.
* Cotidal lines connect points on the rotary wave that experience high tide at the same time.
– Cotidal lines are not evenly spaced.
* This is because tides are shallow-water waves, and their celerity depends upon water depth.
* Corange circles are lines connecting points that experience the same tidal range.
– The lines form irregular circles that are concentric about the node.
– Tidal range increases outward from the node
65
Identify how amphidromic systems rotate in the Northern Hemisphere. Southern Hemisphere?
Southern Hemisphere- clockwise
Northern Hemisphere - counterclockwise
because of Coriolis deflection.
66
Explain how tides operate in long and narrow basins. Define tidal resonance and tidal bore.
Tides Cannot Rotate
* Currents in these basins simply reverse direction between
high and low tide.
* Cotidal and corange lines are nearly parallel to each other.
* Tidal ranges increase if a bay tapers landward because water is funneled toward the basin’s narrow end.
* Tidal resonance- occurs if the period of the basin is similar to the tidal period.
-Resonance can greatly enhance the tidal range.
* A tidal bore- is a wall of water that surges upriver with the advancing high tide.
67
Define flood current and ebb current.
Flood Current- the flow of water toward the land with the approaching high tide.
Ebb Current- the flow of water away from the land with the approaching low tide.
68
Define residence time. Compare and contrast inert and reactive ions. Be sure to include examples of each.
* Residence time - the average length of time that an ion remains in solution in the ocean
- Inert- ions with long residence times, tend to accumulate seawater
EX- Noble gases
-Reactive- ions with short residence times, tend to be removed by biological processes
EX- Fe
69
Explain how changes in salinity, temperature, and pressure affect the density of seawater.
* Density increases as temperature decreases and as salinity and pressure increase
* The addition of dissolved ions to
water lowers the initial freezing point
temperature of the solution.
70
Explain why ocean surface temperature strongly correlates with latitude.
because insolation – the amount of sunlight
striking Earth’s surface – is directly related to latitude.
71
Define isotherm
– lines of equal water temperature – generally trend east-west, except where deflected by currents
72
Define thermocline and mixed layer. Explain how the thermocline differs between the tropics, temperate regions, and the poles.
* Mixed Layer – a nearly homogenous
layer of nearly equal density
* Thermocline - a layer in which water temperature and density change rapidly
with water depth.
- Tropical and subtropical oceans are permanently layered with warm, less-
dense surface water separated from cold,
dense deep water by a thermocline.
- Temperate regions have a seasonal thermocline
-polar regions have none.
73
Explain what causes salinity to change with latitude. Is salinity higher or lower at the tropics compared to the temperate regions? Why?
Salinity Changes with Latitude Due to
Variations in Precipitation and Evaporation
* Highest ocean salinity is between 20 ° to 30° north and south of the equator, because evaporation exceeds precipitation.
* Salinity at the equator and poleward of 30° is low because evaporation is less than precipitation.
74
Define halocline and isohalines
* Halocline - a zone of rapid change
of salinity with water depth
*Isohaline- line or surface on a map that connects points of equal salinity in the ocean
75
Explain how pressure, salinity, and temperature change with depth. Can you have a water mass with a higher salinity rest above a water mass with a lower salinity? If so, explain how.
* Pressure increases regularly with depth
* Temperature and salinity are more variable.
* Higher salinity water can rest above lower salinity water if:
– The higher salinity water is sufficiently warm
– The lower salinity water is sufficiently cold
76
Define pycnocline. What does it coincide with in the tropics? In the temperate regions?
* Pycnocline is a layer within the water column where water density changes rapidly with depth
* Transition between the surface and deep layers.
* Comprises 18% of the ocean basin.
* In the low latitudes, the pycnocline coincides with the thermocline.
* In the mid-latitudes it coincides with the halocline.
77
Define solubility. Explain how decreases in temperature, decreases in salinity, and increases in pressure affect solubility and saturation values of gases
measure of a substance’s tendency to dissolve and go into solution.
* The solubility and saturation values of gases in seawater increase as:
– Temperature decreases
– Salinity decreases
– Pressure increases
78
What layers of the ocean is oxygen most abundant? Where is oxygen least abundant? Why? Explain.
* highest in surface layer and deep layer, and lowest in the pycnocline.
* The surface layer is rich in oxygen because of photosynthesis and diffusion
from the atmosphere.
* The oxygen minimum layer occurs at about 150 to 1,500m below the surface and
coincides with the pycnocline
79
Explain why there is an abundance of oxygen in the deep layer?
* The deep layer is rich in oxygen, because its water is derived from cold surface waters that sank to the bottom.
* Oxygen consumption by respiration is low, because there are fewer organisms in the deep layer.
80
identify the 3 forms dissolved carbon appears in seawater
– Carbon dioxide (CO2)
– Bicarbonate (HCO3^–)
– Carbonate (CO3^2-)
81
Carbonate dominates __________ solutions. Carbon dioxide dominates __________solutions.
Basic
Acidic
82
What factors determine the amount of light that enters the oceans?
– The height of the sun above the horizon
– The smoothness of the sea surface
83
Define photic and aphotic zone.
Photic- The part of the water column penetrated by sunlight
Aphotic- the part of the water column below light penetration
84
Where does light penetrate further? Inshore waters or offshore waters? Why?
Offshore water because Inshore waters have more turbidity, which limits light penetration to a depth of no more
than 20 meters.
85
As salinity, temperature, and pressure increase, what happens to the speed of sound?
The speed of sound increases
86
What happens to the speed of sound in the pycnocline? What is this zone referred to as? What organisms utilize this zone?
Within the pycnocline, the speed of sound
decreases rapidly, because of the rapid
decrease in temperature and only a slight increase in pressure. This zone is referred to as the SOFAR channel (located where sound speed is at a minimum). Whales utilize this zone
87
What is a Niskin bottle?
* The Niskin bottle has valves at each end.
– They automatically close when a weight
(called a messenger) is sent down the
cable and causes the bottle to flip over
and seal itself.
88
Describe what happens to the flow of water from wind-driven surface currents as you increase in depth. Define Ekman spiral.
* With time, wind-driven, surface-water motion extends downward into the water column.
– Speed decreases
– Direction changes because of Coriolis deflection
* Ekman Spiral is the pattern caused by changes in
water direction and speed with water depth
89
Describe Ekman transport and what it can induce along coastal areas
* Ekman transport is the net transport of water by wind-induced motion.
– Net transport of the water in an Ekman spiral has a Coriolis deflection of 90˚ to the direction of the wind.
* Along coastal areas, Ekman transport can induce:
– Downwelling by driving water towards the coast, or
– Upwelling by driving water away from the coast
90
Describe Langmuir circulation. What feature on the sea surface indicates Langmuir circulation?
a complex horizontal helical (spiral) motion that extends parallel to the wind.
Sea stripes
91
Describe geostrophic flow (drawing a diagram may help).
The Coriolis effect deflects water into the center of the gyres forming a low mound of water. As the height of the mound increases, the pressure gradient steepens, pushing the water outwards (downhill) to level the mound. When the pressure gradient equals the Coriolis deflection, the current flows parallel to the wind around the mound- this is called geostrophic flow.
92
Compare and contrast the western and eastern boundary currents of gyres.
– Narrow, deep, and swift currents along the basin’s western edge
– Broad, shallow, and slower currents along the basin’s eastern edge
93
The Guld Stream is an example of a ___________ boundary. These can form warm-core and cold-core rings called ___________.
-meandering
-meanders
94
Define thermohaline circulation and explain what water at the surface is exposed to.
– A density-driven flow of water
– Generated by differences in salinity or temperature
exposed to changes in:
– Salinity, through evaporation or precipitation
– Temperature, through cooling
or heating
– Sea ice formation is especially
important.
95
Where do most deep/bottom waters originate? How did they become deep/bottom waters?
* Most deep/bottom waters originate at the surface where increased salinity and/or lowered temperature raised the water density, due to evaporation, cooling, or ice formation, until these waters sank.
* The water sinks to a density-appropriate level and then slowly flows
equatorward across or along the ocean basin.
* Deep water gradually mixes with other water masses and eventually
rises to the surface
96
What drives inter-ocean basin circulation and the exchange between surface and deep water?
driven mostly by waters of the North Atlantic
97
Describe how water moves from the deep oceans to the surface, from the poles to the equator, etc.
AT the poles, the water is downwelling- as the temperature is decreasing and as the salinity is increasing, the density is increasing (therefore the water sinks to the deep oceans). The water then slowly moves across the ocean floor towards the equator. This is until it starts upswelling due to it running into a continent or because temperature increases and salinity decreases both causing density to decrease. This is the water moving up towards the surface waters.
98
Which of the three oceans (Atlantic, Pacific, Indian) is the most stratified? Least stratified?
Atlantic is the most stratified
Pacific is the least stratified
99
Compare and contrast the Mediterranean Sea and the Black Sea.
Mediterranean-
*Atlantic Ocean water flows in through the Straits of Gibraltar at the surface.
*Warm, highly saline Mediterranean Sea water flows out through the
Straits at the bottom.
Black Sea-
*The surface water is brackish because of high levels of precipitation and river inflow.
*The bottom water is anoxic.
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