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The most abundant dissolved constituent of ocean
RAPID DECREASE IN TEMPERATURE WITH DEPTH...
Why the salinity spikes at 25 degrees to 35 degrees North and South of the Equator?
Because the areas are really dry outside the equator.
What are factors that affect seawater density?
Salinity and temperature (the greatest influence)
What are the layers to the ocean?
- Surface mixed zone
- Transition zone
- Deep zone
- Ocean floor
- between surface layer and deep zone
- Thermocline and pynocline
- sunlight never reaches this zone
- Temperatures are just a few degrees above freezing
- Constant high density water
What is Black and Tan?
2 beers put together one with lighter density and one with a heavier density
Under what conditions would you expect to get the densest ocean water?
High Salinity & low temperatures
What are the main oceanic producers?
- Marine algae
- Bacteria- like archaea
- chemical energy stored in the mass of the ocean's algae is transferred to the animal community mostly through feeding
- Each feeding stage is a trophic level
Is trophic levels a good way to transfer energy?
No only about 2% transfer between organisms
- Bottom dwellers
- A great number of species exist on the shallow coastal floor
- Most live in perpetual darkness in deep water
Thermoclines in the ocean are best developed at...
Sea Ice melting...
Decreases surface seawater salinity because the ic that melts contains less salt than the water in which it originally formed.
classification schemes of diving the ocean into life zones
- 1. Light Availability
- 2. Distance From the Shore
- 3. Water depth
- without sunlight
- Deep ocean
How do you describe a marine life zone?
Sources of energy for Oceanic Productivity?
- Photosynthesis (solar radiation)
- Chemosynthesis (chemical reactions)
What region has the highest overall productivity?
What are the 5 main gyres?
- North Pacific
- South Pacific
- North Atlantic
- South Atlantic
- Indian Ocean
What is the Coriolis effect?
an effect whereby a mass moving in a rotating system experiences a force (theCoriolis force) acting perpendicular to the direction of motion and to the axis of rotation. On the earth, the effect tends to deflect moving objects to the right in the northern hemisphere and to the left in the southern and is important in the formation of cyclonic weather systems.
Does the Coriolis effect how water goes down the drain?
Only works on large systems. The design of the sink has more of an effect then the Coriolis effect does.
Coastal upwelling is due to winds that move nearly parallel to the coast and when combined with the Coriolis effect...
Move surface water off shore
the distance between a trough and a crest
The horizontal distance between successive crests (or troughs)
the time interval for one full wave to a pass a fixed position
Area of ocean or lake surface over which the wind blows in an essentially constant direction, thus generating waves. Wave get no bigger with fetch greater then 1600 km (1000miles)
Wave erosion is caused by
- Wave impact and pressure
- Break down rock material and supplies sand to beaches
- Abrasion- sawing and grinding action of water armed wit rock fragments
Which would have the potential for the largest fetch?
The Pacific Ocean
- Bending of a wave
- Wave arrives parallel to shore
- Wave energy is concentrated against the side and end of headland
- Wave erosion straightens an irregular shoreline
A ridge of sand extending from the land into the mouth of an adjacent bay with an end that often hooks landward
a sand bar that completely crosses a bay
A ridge of sand that connects an island to the mainland.
- Mainly along the Atlantic and Gulf Coastal Plains
- Parallel to the Coast
How do Barrier islands originate?
- longshore model (severed spit)
- Storm sand mound model
- Rising Sea level moel
What is a drainage basin?
The land area that contributes to a stream.
What is the largest drainage basin in the United States?
The Mississippi River
What is the gradient of a stream?
The slope of a stream; generally measure in feet per mile
How does the gradient typically change from the head of a stream to the mouth of a stream?
decreases from the head of the mouth.
What three channel characteristics influence the velocity of water in a stream?
In a bend in a river (a meander), where is the zone of highest velocity located?
At the bottom of the river
What does the zone of highest velocity suggest in terms of erosion and migration of the river channel over time?
will wear away faster
What are some common drainage patterns for stream systems?
- • Dendritic
- • Radial
- • Rectangular
- • Trellis
Under what conditions do drainage patterns form?
The nature of drainage pattern can vary greatly from one type of terrain to another, primary in response to the kinds of rock on which the streams developed or the structural pattern of faults and folds.
What are the three ways in which materials are transported in a river?
- - Dissolved load
- • Suspended load
- • Bed load
What size of materials would we expect to be transported in streams?
Sand, silt, clay
What needs to happen for a river to deposit sediments that are within the suspended load?
The speed needs to slow down and whatever is in the water will be deposited on the shore
What is saltation?
Transportation of sediment through a series of leaps and bounds.
What is alluvium?
Unconsolidated sediment deposited by a stream.
What is a delta?
An accumulation of sediment formed where a stream enters a lake or ocean
Where do deltas form and why?
Form where sediment-sharged streams enter the relatively still waters of a lake, an inland sea, or ocean.
Has the position of the Mississippi River delta remained constant over time?
It has moved over time
What is a natural levee and how do they form?
The elevated landforms that parallel some streams and act to confine their water, except during flood stage.
What is a floodplain?
The flat, low-lying portion of a stream valley subject to periodic inundation.
What is base level (both temporary and ultimate?)
The level below which a stream cannot erode.
Why is it important to understand base level to understand stream erosion and incision?
Defined as the lowest elevation to which a stream can erode its channel. Essentially this is the level at which the mouth of a stream enters the ocean, a lake or another stream. BAse level accounts for the fact that most stream profiles have low gradients near their mouths, because the streams are approaching the elevation below which they cannot erode their beds.
What is a meander?
A loop like bend in he course of a stream.
Do meander's remain in the same place over time?
Yes, the migrate across floodplains
What is an oxbow lake?
A curved lake produced when a stream cuts of a meander
What is a braided stream and what conditions do they represent?
- A complex network of converging and diverging channels that thread their way among numerous islands or gravels bars and look to be interwoven. Wide and Narrow.
- Form where a large proportion of the stream's load consists of coarse material (sand and gravel)
What is groundwater and why is it important?
- Water in the zone of saturation.
- Important because it holds most of the water we need to drink.
What is the zone of aeration?
• Unsaturated zone
- • Pore spaces in the material are filled mainly with
What is the zone of saturation?
Zone where all open spaces in sediment and rock are completely filled with water.
What is the water table?
The upper level of the saturated zone of groundwater
What is a groin?
barriers built at a right angle to the beach that are designed to trap sand
What is breakwaters?
barriers built off shore and parallel to the coast to protect boats from breaking waves
what are seawalls?
Armors the coast against the force of breaking waves
What is a Jetty?
Protects a shipping channel from waves energy and keeps longshore current from filling the channel with sand
What is porosity?
The volume of open spaces in rock or soil.
What is permeability?
A measure of a material's ability to transmit water.
What is an aquifer?
Rocks or soil through which groundwater moves easily.
What is an aquitard?
Impermeable beds that hinder or prevent groundwater movement.
What is an artesian well and what conditions are necessary for one to exist?
A well in which the water rises above the level where it was initially encountered.
What are some environmental problems that are associated with ground water?
- Treating it as a nonrenewable resource
- Land subsidence
- Caused by its withdrawal
What percentage of Earth's surface is covered in water?
What percentage of Earths surface is covered in land?
Which hemisphere of the earth contains more water? Which has more land?
- Northern Hemisphere= Land
- Southern Hemisphere= Water
How many ocean basins are there and what are their names?
There are five ocean basins. These basins are the Pacific Ocean, Indian Ocean, Atlantic Ocean, Southern Ocean and the Arctic Ocean basin
What was the HMS challenger and why was it important?
1872-1876, The first major oceanographic study. Went every major ocean except the Arctic. Ocean depths by dropping a weighted line.
When did ocean coring start and how was it done?
- Drillings started in the 60's/
- Allowed us to get rock samples from ocean depths.
What is a passive continental margin, what are their characteristics, and what is an example?
- Features comprising a passive continental margin.
- Found along most coastal areas that surround the Atlantic Ocean.
What is an active continental margin, what are their characteristics, and what is an example?
- Continental slope descends abruptly into a deep-ocean trench
- Located primarily around the Pacific Ocean
- Accumulations of deformed sediment and scraps of ocean crust form accretionary wedges
- Some subduction zones have little or no accumulation of sediments
- 2 types
- Passive and Active
Some areas are mantled by extensive glacial deposits. Most consist of thick accumulations of shallow water sediments.
- Marks the seaward edge of the continental shelf
- Relatively steep structure
- Boundary between continental crust and oceanic crust.
The gently sloping surface at the base of the continental slope.
Very level area of the deep-ocean floor usually lying at the foot of the continental rise
deep sea fan
A cone-shaped deposit at the base of the continental slope. The sediment is transported to the fan by turbidity currents that follow submarine canyons.
A seaward extension of a valley that was cut on the continental shelf during a time when sea level was lower, or a canyon carved into the outer continental shelf slope, and rise by turbidity.
deep ocean trench
An elongated depression in the seafloor produced by bending of oceanic crust during subduction.
What is the continental shelf? Is it part of the continental crust or oceanic crust?
The gentle sloping portion of the continental margin, extending from the shoreline to the continental slope.
part of the continental crust.
Why is the continental shelf important?
They are shallow enough to allow sunlight to reach the bottom, and are the recipients of nutrient-rich sediments from the adjacent
What is turbidity current and what kind of deposits do they create?
- Downslope movements of dense, sediment-laden water
- Deposits are called turbidites
What is a Seamount?
An isolated volcanic peak that rises at least 1000 meters above the deep ocean floor.
What is a guyot?
A submerged flat-topped seamount
What is atoll and how do they form?
A continuous or broken ring of coral reef surrounding a central lagoon.
What are terrigenous sediments?
Seafloor sediments derived from terrestrial weathering and erosion.
What is Biogenic sediments?
Seafloor sediments consisting of material of marine-organic origin.
What are Hydrogenous sediments?
Seafloor sediments consisting of minerals that crystallize from seater. An important example is manganese Modules.
What is Salinity?
- Total amount of solid material dissolved in water.
- Typically expressed in parts-per-thousand.
What is the the average salinity of seawater?
What are the major components of these salts in the ocean?
What is a thermocline and where do we expect to see them? Where would you not expect to see them?
- Rapid decrease in temperature with depth
- Found in lower latitudes but not Higher
What is density?
- is mass per unit volume
- how heavy something is for its size
What two factors affect the density of seawater?
What is pycnocline?
Density increases rapidly with depth because of colder water
Where would you see pycnocline? Where wouldn't you see this?
Seen in lower latitudes but not higher latitudes
How is the ocean layered by density?
- Surface mixed zone (2%)
- Transition Zone (18%)
- Deep zone (80%)
- Ocean floor
What is plankton?
Floaters on the ocean
What is Nekton?
- all animals capable of moving independently of the ocean currents
- They are unable to move throughout the breadth of the ocean.
What are Benthos?
- Bottom dwellers
- A great number of species exist on the shallow coastal floor
- Most live in perpetual darkness in deep water
What is the difference between phytoplankton and zooplankton?
zooplankton eat phytoplankton
What are the types of tidal currents?
- Flood current (advances into the coastal zone)
- Ebb current (seaward moving water)
What is the intertidal zone?
area where land and ocean meet and overlap
What is the neritic zone?
Seaward from the low tide line, the continental shelf out to the shelf break (90% of commercial fisheries work here)
What is the oceanic zone?
Beyond the continental shelf (relatively low nutrients)
What is the photic zone?
- The light zone
- upper part of the ocean
- Euphoric zone is near the surface where the light is strong
What is the Euphotic zone?
near the surface where the light is strong
What is the aphotic zone?
What is the pelagic zone?
open ocean of any depth
What is the benthic zone?
zone includes any sea-bottom surface
What is the Abyssal zone?
- a subdivision of the benthic zone
- Extremely high water pressure
- Low temperatures
What are the two major factor that control the productivity in the ocean?
Nutrients and Sunlight
What limits productivity in tropical oceans?
The thermocline eliminates the supply of nutrients from deeper waters below
What limits productivity in polar oceans?
Low solar energy limits photosynthetic productivity
What are the most productive oceans?
What are the most important elements in weather and climate?
- Air pressure
- Winds speed and direction
When are the most productive oceans being the most productive?
Spring and Fall
What is the largest component in the atmosphere?
What are trophic levels and what do they allow us to understand?
Chemical energy stored in the mass of the ocean's algae is transferred to the animal community mostly through feeding.
Transfere of energy between trophic levels is very inefficient (about 2%)
What are gyres?
a spiral a vortex
How do Gyres form and what influences them?
any large system of rotating ocean currents. Caused by the Coriolis Effect, planetary vorticity and horizontal and vertical friction.
Do gyres behave the same way in the northern and Southern hemisphere?
- Deflected to the right
- Deflected to the Left
What is the Coriolis effect an why is it important?
As Earth rotates different latitudes travel at different speeds. The change in speed with latitude causes the Coriolis effect.
How do currents relate to gyres?
There are Four main current's that generally exist within each gyre.
What is the current that goes along the eastern seaboard of the United States? Why is it important?
Longshore drift currents
What is upwelling, why does it happen and why is it important?
- The rising of cold water from deeper layers.
- Brings greater concentrations of dissolved nutrients to the ocean surface.
What is thermohaline ciruclation?
A response to density differences
What factors cause thermohaline circulation?
Temperature and salinity
What are thermohaline circulation implications for global oceans?
the desner water moves lower and travels the world.
How do we subdivide the coastal zone?
Off shore, Nearshore,Foreshore, backshore, Coastline,Coast
In this classification scheme, where does the ocean bottom begin to be affect by wave activity?
In the open ocean, how do we determine the depth to which wave activity influences water movement?
As the water’s energy moves forward toward the shore and the depth decreases, the diameter of these circular patterns also decreases. When the diameter decreases, the patterns become elliptical and the entire wave’s speed slows. Because waves move in groups, they continue arriving behind the first and all of the waves are forced closer together since they are now moving slower. They then grow in height and steepness. When the waves become too high relative to the water’s depth, the wave’s stability is undermined and the entire wave topples onto the beach forming a breaker.
What causes breakers to form near the shore?
Because thats where the energy has to stop
What is wave refraction and where does it occur? What landforms are created by it?
- The process by which the portion of a wave in shallow water slows, causing the wave to bend and tend to align itself with the underwater contours.
- irregular shoreline create headlands
What is beach drift and why is it important?
- The transport of sediment in a zig zag pattern along a beach caused by the uprush of water from obliquely breaking waters.
- Transports important sediments
What is longshore drift? Why is it important? and what landforms are created by it?
- The movement of the fine suspended sand and roll larger sand and gravel along the bottom.
- Important because creates good quality sand.
- Creates a spit
What influence coastal erosion?
types of rocks exposed along the shore, the intensity of waves, the nature of coastal currents, ad whether the coast is stable, sinking or rising.
What is an emergent coast? What causes it to be emergent?What feature does it have?
A coast where where land that was formerly below seas level has been exposed either because of crustal uplift or a drop in sea level or both.
What is submergent coast?What causes it to be submergent? What features does it have?
A coast with a form that is largely the result of the partial drowning of a former land surface either because of a rise of seas level or subsidence of the crust or both.
What are tide and what causes them to happen?
Periodic change in the elevation of he ocean surface.
What is Spring tide? What arrangement of the Sun, Earth and moon cause it too happen?
- Highest tidal range that occurs near the times of the new and full moons.
- Happens when the earth and sun and moon are aligned
What is neap tide? What arrangement of the Sun, Earth and moon causes it to happen?
- Lowest tidal range, occurring near the times of the first-and-third quarter phases of the moon.
- Occurs when the moon and the sun act on earth at right angles and each paritally off sets the influences of the other.
What is the Bay of Fundy and what is its significance?
In Nova scotia the high tide is more then enough to float a boat while low tide there is not a drop of water. Shows that the extremes of tides are different everywhere.
What is diurnal tidal pattern?
a tidal pattern exhibiting one high tide and one low tide during a tidal day: a daily tide
What is semidiurnal tidal pattern?
A tidal pattern exhibiting two high tides and two low tides per tidal day with small inequalities between successive highs and successive lows; a semi-daily tide.
What is a mixed tidal pattern?
A tidal pattern exhibiting two high tides and two tides per tidal day with a large inequality in high water heights, low water heights or both. Coastal locations that experience such a tidal pattern may also show alternating periods of diurnal and semidiurnal tidal patterns also called mixed semidiurnal.
Why do we get different tidal patterns around the world?
- different orientation to the sun and moon at different times.
- Different amounts of energy coming in from the waves
What is the difference between weather and climate?
- Weather is constantly changing while climate is the average.
- Climate more specifically is the sum of a ll statistical weather information that helps describe a place or region.
What do we measure to determine weather and climate?
- Temperature, time of the year.
- Weather is a daily measure and climate in an accumulation of many different days of weather.
What is the most abundant gas in the atmosphere?
Approximately how much of our atmosphere is oxygen?
Though an important greenhouse gas, carbon dioxide only comprises how much of our atmosphere?
.0389% or 389ppm
How much of the atmosphere is composed of water vapor? Why is it important?
Varies from almost none to 4% by volume
What are aerosols and why are they important and what are some examples?
- Tiny Solid and liquid particles suspended in the atmosphere.
- Works on surfaces which water can then condense on, can absorb,reflect and scatter incoming solar radiation.
- Also creates the colors in a sunset.
What is the ozone?
A molecule of oxygen containing three oxygen atoms.
Why is the ozone important?
Absorb ultra violet rays from the sun
In what subdivision of the atmosphere is the majority of of the ozone concentrated?
stratosphere, about 15-30 kilometers above the Earth's surface
What is air pressure?
The force exerted by the weights of a column of air above a given point.
How does air pressure change with altitude?
The higher up you are, the less air pressure.
What are typical values for air pressure at sea level? (both in milibars and inches of mercury?
- 1013.2 millibars
- 29.92 inches of Mercury
What are the major subdivisions of the atmosphere?
Troposphere, Stratosphere, Mesosphere, and Thermosphere
What are the subdivision of the atmosphere do we live in?
In which subdivision does the majority of our weather occur?
Can airplanes or jets reach the stratosphere?
Yes on long flights
Why do we have season?
- Result of Changing Sun angle (not distance)
- Changing length of daylight
What name do we give to the longest and shortest days of the year?
- June 21-22 Summer Solstice (Longest Day of the year for N. Hemisphere)
- Winter Solstice Dec 21-22 (shortest day for N. Hemisphere)
What name do we give to the days when daytime and nighttime hours are equal?
What are the Tropic of Cancer and the Tropic of Capricorn and why are they so important?
- Cancer 23 degrees above equator
- Capricorn below the equator
Do polar regions receive the same amount of solar energy as equatorial regions? Why?
Polar region receive less intensive solar radiation because the sun's energy arrives at an oblique angle, spreading over a larger area, and also travels a longer distance through the Earth's atmosphere in which it may be absorbed, scattered or reflected, which is the same thing that causes winters to be colder than the rest of the year in temperate areas.
What are the three ways in which heat can be transferred?Which one is the most important for solid substances? Which ones are important in the atmosphere? Which way do we receive energy from the sun?
- Radiation-through a vacuum (the way we get heat from the sun and atmosphere)
What are the basic classifications of electromagnetic radiation?
Governed by basic laws
Do hot radiating bodies tend to emit more long or short wavelength radiation?
How is the "greenhouse" effect related to the transmission and remission of electromagnet radiation?
The green house affect works like a glass ceiling keeping all chemicals inside. Without this we can not survive because it would let out to many chemicals and let in more radiations from the sun.
What are the three main ways that incoming solar radiation is interfered with by the atmosphere?
What is albedo?
- The more reflective something is the more albedo it has
How much energy is typically absorbed by Earth's surface?
How much energy is lost back into space?
How would we expect yearly temperature to differ between a town along the seashore and one in the middle of the continent?
The town in the middle of a continent will have more extremes because it will trap the heat in and make it hotter and also trap in the cold and make it colder. A seashore has more moderate temperatures because the ocean can reflect away the cold and heat. The ocean is a moderator
If we were to look for the coldest and warmest temperatures experienced on Earth, would we look in the Oceans or the Continents?
How do clouds influence the daily temperature range (both low and highs) Why?
- Clouds reduce the daily temperature and create the coldest nights.
- They are blankets, the keep the heat in at night but keep the sun out during the day
What color flame would be the hottest?
What are important controls of temperature?
- Geographic position
- Cloud cover