MR.GREEN - Oceanography
Terms in this set (52)
Why do water molecules have a bent shape?
Water molecules have a bent shape because the oxygen's bonded electrons push the hydrogens to one side.
What do polar molecules, such as water, act like?
Because they have a positive and a negative end, water molecules act like little magnets.
A hydrogen bond is...
...the attraction between oppositively charged ends of different molecules.
What does it mean for a compound, such as water, to have a high specific heat?
It takes a lot of heat (energy) to make it change temperature.
It takes a lot of what to break the attractions of hydrogen bonds?
It takes a lot of energy.
Why is water a great solvent?
Water is a hydrogen bond, and hydrogen bonds rip apart ionic compounds, like salts.
Does water expand or compact when it freezes? Why?
Water expands when it freezes, because the molecules must push themselves apart to gain the proper spacing to form the crystal lattice.
How many grams of dissolved "stuff" in an average liter of seawater?
How do rivers and stream affect the salinity in oceans?
Rivers and streams carry small amounts of dissolved "stuff" to the oceans, where it accumulates.
How do plankton affect the salinity in oceans?
Plankton regulate the salinity in oceans, by using the dissolved "stuff" to build their exoskeletons.
List the effects of salinity.
- lowers the freezing point
- increases the boiling point
- higher specific heat
- increases the density
What's the "stuff"?
- 55 chlorine ions Cl-
- 30.6 sodium ions Na+
- 7.7 sulfate radical SO4 (2-)
- 3.7 magnesium Mg (2+)
- .3 other
Current is the...
...flow of water along a path.
What are surface current driven by?
Global wind patterns are influenced by...
...atmospheric convection, and the earth's rotation.
Surface currents move in circular patterns within ocean basins, in what direction?
Clockwise in the northern hemisphere, and counter-clockwise in the southern hemisphere.
How do surface current help regulate global temperature?
Surface currents distribute huge amounts of thermal energy (heat) toward the poles.
How does denser water act?
Denser water sinks and spreads.
What can make water more dense?
Diffident temperature and salinity can make water more dense.
How many high tides are occurring on Earth at once? How many hours apart?
There are two high tides occurring on earth at once, and they are twelve hours apart.
Explain what causes both high tides to occur at once.
One high tide is cause by the Moon pulling on the Earth, the other is caused by water being swung around behind the Earth, as the Earth dances with the Moon.
What to the earth sun and moon have to do to create a big tidal range? What is the name of this big tidal range?
To create a SPRING TIDE, the Earth, Sun, and Moon have to line up, by doing this the effects of the Sun and the Moon combine.
What do the Sun, Earth, and Moon have to do to create a small tidal range? What is the name of this small tidal range?
To create a NEAP TIDE, the Sun, Earth, and Moon have to form a right angle, although the Sun fights for the Earth's water, because the Moon is closer to the Earth, it wins.
The amount of dissolved stuff in water (more stuff = higher salinity)
Device that floats at different heights, depending on water density (salinity)
The amount of heat that must be added to or take away from a material in order to change its temperature by a given amount.
- water has a high specific heat, meaning that a lot of energy must be added to it or taken away from it in order to change its temperature
- stated most simply, water's high specific heat makes it difficult to change its temperature
The attraction between the positive ends of water molecules and the negative ends of other water molecules.
A bond between atoms in which electrons are shared. Bonds between hydrogen atoms and oxygen atom in water are covalent.
A substance that does a good job of dissolving things. Water is sometimes called the "universal solvent" because its hydrogen bonds rip apart some substances.
Driven by wind; move in the upper 1000m of water.
- move in circular patterns within ocean basins; clockwise in the northern hemisphere and counterclockwise in the southern hemisphere.
- take warm water away from the equator and regulate global temperature by carrying toward the poles.
Driven by differences in density between different masses of water.
- the coldest, saltiest masses of water will sink and spread across the ocean bottom.
- the worldwide patterns of density currents is known as the Great Ocean Conveyor Belt.
When wind moves surface water away from a coastline, cold, deep water is pulled upward to replace it in a process called upwelling.
Normal surface current flow east to west in the Pacific Ocean just south of the equator, resulting in upwelling off South America (good fishing) and warm water building up near Indonesia and northeastern Australia.
- in an El Niño year, the current flows west to east, and piles up the warm water on the opposite side of the Pacific.
- the total amount of heat carried by the water is equivalent to more than a million atomic bombs; enough to affect global weather patterns.
A warm current that runs along the east coast of the USA and swings out across the northern Atlantic Ocean.
Shallow (generally less than 500ft) offshore area; parts of it were above water during previous ice ages.
Shallowly sloping (think movie theater side) part of the sea bed that begins at the edge of the continental shelf and descend to several thousand meter.
Exists at passive continental margins, connecting the continental slope to the abyssal plain.
- barely detectable slope.
Vast, flat area that covers more than 50% of the Earth's surface.
- deepest part of the ocean (except for trenches).
Vast mountain ranges in the middle of the abyssal plain.
- built by volcanic activity from divergent boundaries.
HYDROTHERMAL VENT (BLACK SMOKER)
Vents emitting super-hot water (750˚F) and a mix of gases including hydrogen sulfide.
- found at mid-ocean ridges.
- support ecosystems that are based on bacteria that can survive in the total absence of light.
DEEP SEA TRENCH
Formed by an oceanic plate subsiding.
ACTIVE CONTINENTAL MARGIN
Edge of a continent where there is a tectonic plate boundary.
PASSIVE CONTINENTAL MARGIN
Edge of a continent where there is no tectonic plate boundary.
A mountain built upward from the seafloor, usually by a volcanic activity.
A flat-topped seamount which has been weathered away and no longer reaches the surface of the ocean.
Microscopic photosynthetic organisms (plants and algae).
- base of the food chain in the ocean.
- largest source of oxygen for the planet.
- feed on phytoplankton (and each other).
- help regulate ocean salinity by using dissolved stuff to build their hard body parts.
There are two occurring on Earth at any one time; twelve hours apart; opposite from each other.
- one high tide is nearest the Moon, caused by the Moon's gravitational pull.
- one high tide opposite the Moon, slung out behind the Earth by the rotation of the Earth-Moon system (the "dance").
Low tidal range, caused by the Moon, Earth, and Sun forming a right angle.
- Sun and Moon fight for the Earth's ocean and do a good job canceling each other.
High tidal range caused by the Moon, Earth, and Sun lining up.
- Moon and Sun pull in unison, causing high high tides and low low tides.
A tidal wave caused by a mass of water piling into a bay or river mouth all at once.
BAY OF FUNDY
Bay in Canada between Nova Scotia and New Brunswick; largest tidal ranges in the world (difference of more than 50ft sometimes).