Nearly all of Earth's surface water is contained in
The oceans represent far less water than the water (H2O) that is bound to minerals in Earth's interior
Water on Earth (and hence ocean water) most likely formed
(A&B) -During the first 0.5 x 10^9 (half billion) years of Earth's history -From emission (degassing) of volatiles from Earth's interior
The Scientific Method
Is an emperical approach based on observations and facts
It is easier to prove a theory or hypothesis than it is to disprove a theory or hypothesis
The "Goldilocks Principle," in part, suggests that Earth has just the right position in the solar system to allow retention of liquid water and habitability for life
The course web site has an article about a violent storm in 1992 that tossed 20 containers of rubber duckies overboard
Extreme variation in the ocean's temperature is prevented by water's
Key physical properties of water include:
(B&C) -Surface tension, which the property that makes water form into droplets when it's raining -Heat capacity, which is a measure of the heat required to change the temperature of water
Latent heat is the
(A&C) -Energy required to change ice to liquid water -Important in energy transfer from the ocean to atmosphere
Heat capacity is a measure of temperature of water
Land heats and cools more rapidly than bodies of water
Latent Heat is
The energy needed to change the phase of a substance (i.e ice to liquid water)
It takes more heat to warm up water than it does to warm up rocks and soil
The density of liquid water is
higher than that of ice, which is why ice floats in water
Seawater salinity is
(A&B) -35 ppt on average -35 g/kg on average
One important connection between seawater chemistry and Earth's surface is rock weathering
The chemistry of ocean water is the same as river water
The latent heat of fusion (melting) for water is 80 cal per gram. How much heat energy is required to melt 10 grams of ice? a) 80 calories
Seawater salinity is the same in all parts of the world ocean
The water cycle involves
All the above: evaporation, precipitation, condensation
Ocean Chemistry is influenced by
All the above: Inputs such as river water and volcanic gases, outputs such as evaporates and interaction of seawater with the seafloor, rock weathering, marine life including plants and animals
Residence time of an element in seawater can be calculated from the total amount of the element and the input rate
A water molecule may evaporate from the ocean, become part of a cloud and then become a rain drop that becomes part of a river and flows back into the Ocean. The average "residence" time for a molecule to make this trip is ~ 4,000 years
The residence time of an element in seawater is an indication of how rapidly it is cycled. Long residence times indicate low demand and/or infrequent precipitation as a mineral
Gases dissolve more readily in cold seawater than in warm seawater
The ocean is
Stratified into layers, such that shallow water has different properties than deep water
Marine animals break down water molecules to obtain O2
The density of seawater
Increases as temp. falls and salinity increases
Freshwater reaches max density at the freezing point
Water in the world ocean came from Earth's interior
A&C -This is a falsiﬁable, scientiﬁc hypothesis! -This is reasonable, based on what we know about Earth's composition and internal structure
Which is the best answer
Viscosity is a measure of resistance to shear motion
Consider: two identical pots, filled with equal masses of fluid, on identical burners on a stove. Pot A is filled with a fluid of low heat capacity Pot B is filled with a fluid of high heat capacity After a time.....
The material in Pot A has reached higher temp.
It's game day, and you want to keep your Pepsi cold as long as possible! You should ﬁll your cooler with:
A material with high heat capacity
Hurricanes strengthen and gain energy by
Release of latent heat at high elevation within the eye, which causes air to warm-up and rise
Ocean chemistry is a balance between inputs and outputs
Seawater salinity: Which is/are true?
A&B -The most abundant element dissolved in water is Cl -The element sodium is present in table salt and it is dissolved in seawater
Which of the following are true:
Mineral deposits, such as halite and gypsum represent outputs for chemicals in the ocean
Solubility of Gases in Seawater:
B&C -Cold freshwater can dissolve more gas than warm saltwater -Fishes need oxygen to live and they get that by breaking O molecules
The concentration of dissolved oxygen in seawater is, in part, determined by
All of the above: water temp., water salinity, relative amount of respiration, relative amount of photosynthesis
Which go together
Salinity & Halocline, density & pycnocline, temp. & thermocline
Which of the following are correct
All of the above: -If more solar energy is retained by earth than reflected or reradiated, earth atmosphere will warm -On avg. about 30% of incoming solar radiation is reflected back to space without an impact on earth surface temp. -The sun radiates mostly short-wave energy (visible light) whereas the Earth radiates long-wave energy (infrared) -So-called greenhouse gases absorb lopng-wave energy in the atmosphere and cause temp. to increase
Which of the following statements is correct about the Earth?
All the above -Incoming energy from the sun is the primary means of heating the tropics -Heat transfer from low to high latitudes plays an important role in the pattern of ocean currents and large scale winds -Ocean currents and winds transfer heat from low to high latitudes
Why is there generally low pressure over the equator and high pressure at 30 degrees N and 30 degrees S?
All the above -Lots of solar energy reaches the equator and warms up the air, causing it to rise -The equator receieves a surplus of energy relative to polar regions and this causes winds, in the upper atmosphere that blow N and S away from the equator -Downward winds at 30 degrees N and 30 degrees S cause high pressure below them
Why don't the tropics boil and the poles freeze over?
Heat is transferred from the tropics to the poles
Solar energy received at Earth's surface is high in the zones centered around the zones centered about 20 degrees N and S because
These areas are generally clear and not covered by clouds
Which statement is correct about this plot?
B&C -Heat is required to change ice to water and this is known as latent heat -Once the ice melts heat will cause temp. to rise this is known as sensible heat
Most of the earth's surface water is
In the ocean, glaciers & ice caps
What is the residence time of deep water in the large basins
10 coconuts fall on the beach each day. There are about 20 on the beach. Calculate the residence time.
When scientists carry out investigations they typically
All the above: -Construct one of more hypothesizes -Make observations and collect data -Test the hypothesis by trying to just prove it -Evaluate or change hypothesize on the basis of results
Which of the following list of elements or molecules represents the correct rank order from highest to lowest concentration in sea water
None of the above
The Goldilocks principle as applied to the origin of water on Earth suggests that one earth has just the right position in the solar system not too close to the sun and not too far away and two when it was forming it had just the right mass large enough to retain water vapor
Rachel Carson suggested that rain and other factors weather the continents and that rivers delivered dissolved rock to the world ocean which would cause changes in ocean chemistry through time
Water molecules have polar (unequally distributed) charge that leads to many of waters unusual characteristics
Goldilocks and water on Earth. Recently a team of astronomers announced that
They had detected 2 earth size planets circling very close to a star called Kepler-20
Seawater chemistry is influenced by rock weathering
The thermocline, halocline, and pycnocline
Are names for the region between ocean surface water and deep water
Phosphate has a shorter residence time than most major elements in seawater b/c
It is cycled very rapidly by organisms b/c it is essential to their metabolism
Which is greater - the average depth of the ocean, or the average elevation of the continents?
The avg. depth of the ocean
Why do we say there's one world ocean?
Because all the oceans are connected
How is ocean deep water different from shallow water?
It has different salinity, temperature, chemical composition, and density. Deep water is colder, saltier, and therefore, denser than surface water
What did Rachel Carson suggest about how ocean chemistry may have changed over geologic time?
Due to rain and other factors, bringing other sources of water back to the ocean. Pollution would also be a factor
How did geosc040 get it's name: "The Sea Around Us" ?
Rachel Carson's book of the same title
How to calculate residence time of an element in seawater
(amount of element in the ocean) divided by (the rate at which element is added to/removed from the ocean)
Why does ice float?
The density of liquid water is higher than that of ice so it floats
How do temperature and salinity influence the solubility of gas in seawater?
Solubility decreases with increase in temp. and increase in solubility
Names of ocean's density zones
Surface Zone, Pycnocline, and Deep Zone
How is the ocean stratified by density?
The least dense water on top and the most dense water on the bottom. Because water has low viscosity, denser water masses sink to the bottom, whereas less dense water masses lie nearer the surface.
Sensible heat describes temperature changes via heat capacity, is the detectable increase or decrease in heat.