AICE Marine Science Study Guide for Exam+

Erosion

the removal of rock/particles moved by action of waves/wind/rain

Deposition/Sedimentation

the dropping/depositing/accumulating of rock/particles by waves/wind

Plate Tectonic Theory

-Earth's crust/lithosphere is made of plates

-Continents lie on plates

-Plates are moving slowing on top of asthenosphere

-Plates move do to convection currents in the asthenosphere

-Plates meet at boundaries; convergent divergent and transform

-Plate movement causes earthquakes, mountain building, and volcanic eruptions

Divergent Boundary

two plates moving apart from one another

Convergent Boundary

where two (or more) tectonic plates or fragments of the lithosphere move toward one another and collide, one forming on top of the other.

Transform Boundary

two or more plates sliding past each other

Littoral Zone

Area between high and low water mark/areas submerged at high tide and exposed at low tides

Rocky Shore

-Cold temperature

-Erosional

-pebble substrate

-snail (attach) crab (hide/camo) bacteria (burrow)

Muddy Shore

-Flat slope

-Depositional

-Sand/clay substrate

-bacteria, worms (burrow) algae (attach)

Sandy Shore

-Depositional

-Fine to coarse substrate

-only burrowing organisms (Plankton, jellyfish, and mollusks)

Estuary

-Blackish Water

-Low dissolved oxygen

-Low wave action

-Depositional

-Fine, muddy silt substrate

-Seaweed, fish algae

Delta

-Blackish Water

-Movement of sedimentation

-Fine to silt substrate

-Worms (burrow) crabs fish

Mangrove

-5-20 degrees celcius, tropical climate, low dissolved oxygen, low wave action, deep sediment

-Muddy to silt sediment

-Depositional

-Bacteria, snails, ferns (burrow/attach)

Larger; Smaller

Particle size on sandy shore is _____________ in particle size and _________________ for a muddy shore.

Thermocline

interface between two layers, where the temperature decreases abruptly as the depth increases.

Halocline

A significant change in salinity as the depth increases.

Salinity

the measure of all the salts dissolved in water.

Solubility

a chemical property referring to the ability for a given substance, the solute, to dissolve in a solvent.

Tidal Range

the difference in height between the highest high and lowest low tides

Geomorphology

The shape of the shoreline/coastline, the shape of the tidal basin.

Upwelling

vertical movement of cold deep water that reaches the surface caused by costal slope or mid ocean ridge and brings nutrients to the surface

35 ppt

Average salinity of the oceans

Sodium and Chloride ions

What are the two most abundant ions which make up the salt found in seawater

Factors which affect the chemical composition of seawater

-Dissolution of atmospheric gases from either mixing of air or volcanic eruptions

-Carbon dioxide, sulpher dioxide, chlorine dissolve with water and change the pH more acidic

List and explain the sources of salts in the oceans

Weathering of rocks, volcanic eruptions and decomposition of marine organisms

The factors which affect salinity changes throughout the year (from winter to spring)

-temperature increasing evaporation rate of water, salinity increasing

-rainfall/precipitation dilutes water, salinity decreases

How surface salinity varies with distance from land (& know why this happens)

Salinity decreases the closer to the shore from runoff/river outflow diluting water.

What is the relationship between surface salinity and latitude?

-Salinity increases from 300 degrees N and S of the equator due to temperature

-Salinity decreases at the poles due to ice forming and melting of ice particularly at the surface but brine denser colder water is usually below

Explain how volcanoes and runoff affect the chemical composition of seawater

Volcanoes release carbon dioxide, sulfur dioxide, chlorine from hydrochloric gas, flourine gas

Decreases

As temperature increases, density ____________.

Increases

As salinity increases, density _______________.

Know how the levels change as you go deeper into the ocean and know why levels of dissolved oxygen in the oceans fluctuate.

-Oxygen increases at the surface due to wave action/wind/mixing of air.

-Oxygen increases by the presence of photosynthetic phytoplankton producing oxygen

-Oxygen is used up by marine organisms during respiration decreasing oxygen

-Oxygen increases as depth increases due to solubility of gases is greater when temperature decrease.

Biological factors for why the concentration of oxygen in seawater varies.

Photosynthetic phytoplankton producing oxygen and marine organism using oxygen during respiration

Physical factors for why the concentration of oxygen in seawater varies.

-Pressure decreasing then oxygen decreases, temperature decrease then oxygen increases, salinity increases then oxygen decreases

-Turbulence from mixing of air/wind/wave action then oxygen increases

Differences between the oxygen concentrations in fresh water and in sea

-Fresh water is higher in oxygen concentration than sea water

-In a normal freshwater stream, one wants to ideally have a dissolved oxygen (DO) concentration of at least 6 ppm or greater. One does not want to have less than 4 ppm DO in the water because at this concentration range, fish can normally not survive.

Differences between the oxygen concentrations in fresh water and in sea

-Oxygen is more easily dissolved into water with low levels of dissolved or suspended solids. Waters with high amounts of salt, such as the ocean (which contains about 35 grams of salt for each 1000 grams of water) have low concentrations of DO. As the amount of salt in any body of water increases, the amount of dissolved oxygen decreases. An increase in salt concentration due to evaporation of water from an ecosystem tends to reduce the dissolved oxygen available to the ecosystems inhabitants.

Increases

As temperature decreases, solubility _________________

Atmospheric dissolution

mixing of air from wind/wave action (oxygen and carbon dioxide can enter oceans from dissolution)

Describe how atmospheric gases get into seawater

-Atmospheric dissolution

-Volcanic eruptions release sulfur and chloride gas when enter oceans combine with water to form access and change salinity

How are tides caused

-the gravitational pull between the Sun, Earth and Moon

-Moon's gravity pulls on the Earth, pulling the ocean waters toward the Moon

-This pull creates a bulge of water on Earth

-The bulge on the exact opposite side of the Earth is created by centrifugal forces as Earth rotates

-These bulges create high tides and on side of Earth with no bulge is low tides

Factors that affect tidal range

-Alignment of the Earth, Sun and Moon

-Geomorphology (shape of the coast)

-Wind

-Air pressure

-Size of the body of water

Neap tides

-When Sun, Earth and Moon from a right angle

-Occurs during 1st and 3rd quarter moon

-Not a strong gravitational pull

Spring tides

-large tidal range

-When Sun, Earth and Moon form a straight line, 180 degrees

-Occurs during full and new moon

-Greatest gravitational pull

Ocean Current

Movement of water in one direction

Explain how wind and the shape of the sea bed produce ocean currents and upwelling

-Upwelling is the process that occurs when wind blows across the ocean surface, pushing water away (displacement of surface water). The deeper colder water then rises up from beneath the surface to replace the water that was pushed away. Upwelling areas are regions where significant vertical movement of water occurs. This can happen near shore because of the slop of the land or in the open ocean. A mid-ocean ridge cause upwelling by deflecting deep water currents upwards. Upwelling brings nutrients to the surface.

East to West

Normall winds blow from ________ to _________, during El Nino year the trade winds are weakened and sometimes reversed

Lack

Normally winds blowing east to west allow for upwelling to occur of coast of South America, during El Nino year because of the weakening of the winds, there is a ______________ of upwelling

Increase

Normally water off coast of South America is cool, during El Nino year the winds weakening and lack of upwelling, _______________ warmer waters of the coast of South America.

Rise; rougher seas

Normally strong upwelling produce smoother seas off the coast of South America, during El Nino year the winds weakening cause surface water to __________ off the coast of south America creating ______________ _________.

Explain how El Nino conditions affect the fish populations near the coast of South America

Weakening of winds causes lack of upwelling

Lack of upwelling means less nutrients

Less nutrients, less phytoplankton growth

Less phytoplankton, less food for fish

Less food for fish, less fish population and/or fish die

Explain why India experiences a wet summer monsoon

In the summer months, from May until August, the land heats up quickly and there is relatively large temperature difference between Central Asia and the Indian Ocean. Air over the land warms, becomes less dense and rises. this draws in air saturated with water vapor from the Indian Ocean, from a south-westerly direction. The summer monsoons bring thunderstorms and exceptionally heavy rain. It has been estimated that these summer monsoons bring over 80% of India's annual rainfall.

Features of a cyclone

A large, low-pressure centre and many thunderstorms with strong winds and heavy rain

Describe conditions necessary for the formation of a tropical cyclone

Must be over warm sea water (with a temp of at least 26.5 degrees Celsius) and must be in a low pressure area where evaporation of water occurs. As the water vapor rises, it condenses and releases large amounts of heat energy (latent heat of condensation). This heat energy further increases evaporation, driving the development of the cyclone. As a result of the rotation of the Earth and the Coriolis Effect, the whole cyclone system starts to spin.

Possible effects of cyclones on coastal communities

-High winds cause structural damage to property&homes

-Damage to roads and habitats

-Reduced protection to shores affecting mangroves

-Storm surges cause flooding

-Coastal wetlands become flooded with salt water

-Death and disease

One beneficial effect that may occur when a cyclone reaches land

-Rain to dry areas

-Replenish nutrients to areas that were drought

- See dispersal

-Destroys/removes nonnative plant

Monsoon

Wind systems that exhibit a pronounced seasonal reversal in direction

Land breeze

-Occurs during night time

-Water is warmer than land due to waters high heat capacity

-Wind direction blows from land to sea

-Area of low to high air pressure

Sea breeze

-Occurs during the day

-Land is warmer than sea from the sun

-Wind direction blows from sea to land

-Area of high to low air pressure

Evaporation

Process that provides the latent energy for the development of the cyclone

Decreases

Air pressure __________________ as air rises during a cyclone

How a mid-ocean ridge is formed

an underwater mountain range, formed by plate tectonics. This uplifting of the ocean floor occurs when convection currents rise in the mantle beneath the oceanic crust and create magma where two tectonic plates meet at a divergent boundary.

Subduction

How is a deep ocean trench formed

Explain why sandy shores a low biodiversity has compared to rocky shores.

-unstable / shifting, sands / substrate. few species adapted to live there / few species can live there;

-must eat anything available / few producers / less food available ;

-species burrow to survive / refrence to infauna ;

-few / no suitable substrate for attachment ;

State three conditions that are suitable for tropical reef-building coral growth on the Great Barrier Reef.

1) warm waters (within stated range of 16–35°C / 60–95°F) ;

2) shallow ; clear water / low turbidity / low nutrient ;

3) high light penetration ; high light intensity ;

In late summer of 2016 around 30% of the Great Barrier Reef coral polyps died.

This was particularly noticeable on the northern end of the reef.

Suggest three causes for the death of the corals.

1) disease ; acidification ;

2) air exposure ; natural disaster (tsunami / earthquake) ;

3) water pollution ; rising sea temperature ;

Explain why coral reefs the region with the highest mean primary productivity are.

coral reefs contain many zooxanthellae / many photosynthetic organisms ;

(warm) temperatures 16–35 °C ;

shallow waters; (for) maximum (sun)light penetration ; higher rate of photosynthesis

Weathering and erosion affect the type and morphology of shorelines that develop in the

littoral zone.

Explain how erosion can affect the morphology of the different types of shore. In your

answer include reference to the four main types of erosion.

1) ice / glaciers move, material / rocks ;

2) water / run-off carries sediment ;

3) wind / blows particles to new areas ;

4) gravity – particles tumble from high areas to low

5) rocky shore – high levels of erosion (carrying material away quickly)

6) sandy shore – low erosion levels ;

7) deposits small sand particles (on shore) ;

8) muddy shore or estuary – low(est) erosion levels

Describe the features of a sandy shore ecosystem and outline how the organisms that live there are adapted to cope with the abiotic factors in this environment.

1) low food availability ;

2) easily moves / subject to wind erosion / subject to water erosion, e.g. longshore drift ;

3) low productivity ;

4) no substrate for attachment ;

5) small particles ;

6) gentle slopes ;

7) low biodiversity ;

Mangrove forests develop in the littoral zone of some tropical and subtropical coasts.

Explain how the red mangrove, Rhizophora mangle, is adapted to this environment.

1) tough / leathery leaves ;

2) that reduce evaporation ;

3) prop roots ;

4) provide stability on, muddy / unstable, substrate ;

5) due to high salinity of the water ;

🌎 Ocean Zones
1. By Depth (Vertical Zones)

• Sunlight (Photic) Zone – Top layer, sunlight reaches, photosynthesis happens.

• Aphotic Zone – No sunlight, very dark, no photosynthesis.

🌎 Ocean Zones
2. By Distance from Shore

• Intertidal Zone – Between high and low tide.

• Neritic Zone – Shallow water near coast (very productive).

• Oceanic Zone – Deep open ocean.

🌎 Ocean Zones
3. By Ocean Floor

• Continental Shelf – Shallow edge of continent.

• Continental Slope – Steep drop-off.

• Abyssal Plain – Deep, flat ocean floor.

🌡 Salinity & Temperature

• Salinity = Amount of salt in water.

• Average ocean salinity = 35 ppt.

• Higher salinity = water is more dense.

• Cold water = more dense than warm water.

• Density differences cause ocean currents.

🌊 Ocean Currents

Surface currents caused by:

• Wind

• Earth’s rotation (Coriolis Effect)

🌊 Ocean Currents

Deep currents caused by:

• Differences in temperature + salinity

• Called thermohaline circulation

🌙 Tides

• Caused by gravity of:

  • Moon (main cause)

  • Sun

• High tide – Water rises

• Low tide – Water falls

• Spring tide – Biggest tidal range (sun + moon aligned)

• Neap tide – Smallest tidal range

🌊 Waves: What is it?

• Caused by wind.

• Crest – Top of wave.

• Trough – Bottom of wave.

• Wavelength – Distance between crests.

• Tsunamis caused by underwater earthquakes.

🐠 Marine Ecosystems

1. Coral Reefs

• Warm, shallow water.

• Very biodiverse.

• Coral has symbiotic algae (zooxanthellae).

🐠 Marine Ecosystems
2. Estuaries

• Fresh + salt water mix.

• Very productive.

• Important nursery for fish.

🐠 Marine Ecosystems
3. Mangroves

• Trees in coastal areas.

• Protect shoreline.

• Prevent erosion.

🌿 Food Web

• Producers – Phytoplankton (make food using sunlight).

• Primary consumers – Eat producers.

• Secondary consumers – Eat primary consumers.

• Apex predator – Top of food chain.

Energy decreases as you move up the food chain.

🐡 Adaptations

• Camouflage – Blend in.

• Countershading – Dark top, light bottom.

• Bioluminescence – Make their own light.

• Streamlined bodies – Swim faster.

⚠ Limiting Factors

• Sunlight

• Nutrients

• Temperature

• Oxygen

• Salinity

If one is too high or too low → organisms struggle to survive.

🌍 Human Impact

• Overfishing

• Pollution (plastic, oil spills)

• Ocean acidification (caused by CO₂)

• Climate change (warmer water, coral bleaching)

describe how sodium chloride dissolves in water

Sodium chloride (table salt) dissolves in water because the water molecules pull apart the sodium (Na⁺) and chloride (Cl⁻) ions, surrounding them and keeping them separated so they spread out evenly in the water.

define the term salinity

Salinity is how much salt is dissolved in water.

describe the importance of ice floating to the marine ecosystem

Ice floats because it is less dense than liquid water, and this is important to the marine ecosystem because floating ice creates habitats for animals (like polar bears, seals, and penguins), helps keep the ocean from freezing solid, and reflects sunlight to regulate Earth’s temperature.

|Subatomic particle :electron:

|Charge:-1|Number present in a sodium atom:11|

|Subatomic particle : proton:

|Charge: +1|Number present in a sodium atom: 11|

|Subatomic particle : neutron:

|Charge: 0|Number present in a sodium atom: 12|

state the chemical formula of calcium carbonate

The chemical formula of calcium carbonate is CaCO₃.

describe how calcium carbonate from animals can become part of rocks

Calcium carbonate from animals, like shells and skeletons, can pile up on the ocean floor after the animals die. Over time, the layers get pressed together and harden, turning into rock like limestone.

Algae require magnesium for growth Explain why a lack of magnesium can limit the growth of algae

Algae need magnesium to make chlorophyll, which they use for photosynthesis. Without enough magnesium, they can’t make enough chlorophyll, so they can’t make food properly, and their growth slows down.

describe how sodium chloride dissolves in water

When sodium chloride (table salt) is put in water, the water molecules pull the sodium and chloride ions apart. The positive part of water attracts the negative chloride ions, and the negative part of water attracts the positive sodium ions. This separates the salt into ions and makes it disappear in the water.

explain how this ionic structure forms from sodium atoms and chloride atoms

A sodium atom loses one electron to become a positively charged ion (Na⁺), and a chlorine atom gains that electron to become a negatively charged ion (Cl⁻). The opposite charges attract, so they stick together to form the ionic structure of sodium chloride (NaCl).

A fish may swim throughout the water column in this estuary explain how changes in abiotic factors from increasing depth could affect the availability of oxygen for fish

As a fish swims deeper in the estuary, abiotic factors like light, temperature, and pressure change. Deeper water is usually colder and has less light, and sometimes less movement. This can make less oxygen available for the fish because oxygen levels often drop as depth increases.

explain why dissolved oxygen concentration is high in the surface waters of the ocean

Dissolved oxygen is high in the surface waters of the ocean because the water is in contact with the air, so oxygen from the atmosphere can mix in, and sunlight allows plants and algae to make oxygen through photosynthesis.

suggest why it is unusual for fish that live at depths of over 800m to be found in surface water

It is unusual because fish that live deeper than 800 m are used to very cold, high-pressure, and dark conditions, so they usually cannot survive near the warm, low-pressure, bright surface water.

describe and explain the effects of evaporation and precipitation on the salinity of sea water

• Evaporation: When water from the sea turns into vapor and leaves, it takes only water, not salt, so the salt stays behind. This makes the sea water saltier.

• Precipitation (rain or snow): When fresh water falls into the sea, it adds water but no salt. This makes the sea water less salty.
  In short: evaporation increases salinity, and precipitation decreases salinity

explain how the concentration of dissolved oxygen varies with depth in the open ocean

In the open ocean, the concentration of dissolved oxygen is usually high near the surface because of air contact and photosynthesis by plants and algae, then it drops in the middle depths because organisms use oxygen as they decompose organic matter, and finally it can increase slightly in the deep ocean where cold water holds more oxygen and there is less decomposition.