Exam 2 Flashcards
What makes up the water molecule?
1 oxygen atom, 2 hydrogen atoms bonded together
What is the basic atomic structure for water (molecule)?
- nucleus made up of protons (+) and neutrons (neutral)
- electrons (-) on rings that orbit nucleus
What is the Octet rule?
it is the tendency of atoms to have stability with their electrons, all atoms/molecules ultimately want 8 electrons in their outer shell (valance)
What is h2o’s bond angle?
105 degrees
Whats unique about the h2o molecule?
- universal solvent
- electromagnetic
- three phases (solid, liquid, gas)
What type of bond holds h2o together?
Covalent bonds
What kind of charge does oxygen carry? hydrogen?
O2 has a negative charge, H has a positive charge
What are the type of bonds in the water molecule?
Covalent bonds hold elements together and form when two or more atoms share electrons to fill their outermost electron shells.
Hydrogen bonds occur when the partial positive charge of a hydrogen atom bonds to an electronegative molecule, usually oxygen and creates surface tension
Which is stronger covalent or hydrogen?
covalent
What is cohesion?
when water wants to “stick” and the “glue” is a hydrogen bond. This leads to surface tension that is at the top (water creates a surface).
Water is a ____ molecule? (in terms of polarity)
dipolar
What is dipolar?
an electrically neutral molecule carrying a positive and a negative charge
why is water a polar molecule?
It behaves as an electromagnet where the Hydrogen end has a (+) charge which attracts to a (-) side of another molecule and the O2 has a (-) charge attracting to a (+) end of another molecule
What is the result of water being a polar molecule?
the process of polarity in water dissolves substances that is why water is a universal solvent.
What happens to NaCl in water?
NaCl dissolve because sodium (Na) has a + charge which attracts to oxygens (-) and chloride (Cl) has a - charge which attracts to hydrogens (+) charge.
T/F NaCl individually is dangerous, sodium is a metal and chloride is a gas
True, as individual elements they are very dangerous but together they make up salt
How do water phases change?
One must either remove/add heat energy. If you add heat, molecules move at a faster rate and change from either solid to liquid or (at a much higher temp) from liquid to gas. If you remove heat energy, the opposite occurs the liquid will turn into a solid.
Explain the structure of solid water (ice)
They are hydrogen bonds holding a 3D crystalline structure. The molecules in this state are locked in place and all H bonds are connected
Explain the structure of liquid water
Most molecules/ H bonds are connected in this phase.
Explain the structure of vapor (gas)
In this phase, the molecules are independent “zooming around” and have no H bonds.
What is heat capacity?
the amount of heat required to raise temp of one gram (of any substance) by 1 degree celsius
What does it mean when a substance has a high heat capacity
takes alot of heat to change the substance
What is water’s heat capacity? (is it low or high)
water has a very high heat capacity, due to thermal inertia (hydrogen bonds)
What is an example of water’s heat capacity?
oceans absorb/release huge amounts of heat with very little change in temperature.
What is sand’s heat capacity? (high or low)
Sand has a low heat capacity because it requires less heat in order to make it hot. That is why sand turns very hot while ocean doesnt.
How are coastal climates influenced by heat capacity?
The heat capacity of the ocean is much greater than that of the atmosphere or the land. As a result, the ocean slowly warms in the summer, keeping air cool, and it slowly cools in winter, keeping the air warm.
How does Salinity and temperature affect density?
As temp decreases, density increases and as temp increases, density decreases. When we add salt, density is also increased.
So, cold salty waters are going to be denser than warm and cold (non salty) water.
What is Density?
Density is mass over volume and in pure watter, density is 1 gm (mass) OVER cm^3
What happens to cold salty water in terms of thermal contraction? How about warm waters? (thermal expansion)
Cold salty water sinks to the bottom and contracts.
Warm water floats because they are less dense and therefore thermally expand.
what happens to water at the poles (salinity, temp, density)
At the poles/high latitudes, cold salty waters sink
What two types of energy are related to water?
Kinetic and Heat Energy
T/F only oceans produce hurricanes
True
What is the average salinity of seawater?
35 (parts per thousand-ppt) or 3.5 percent
What are the most abundant salt ions?
Chloride and sodium (most abundant in surface salinity)
Where are the highest salinity points (latitude)
highest at mid-latitudes
example: Mediterranean Sea
Surface Salinity is _______ where precipitation is _________
(lowest/highest), (highest/lowest)?
highest, lowest
T/F Rivers increase salinity.
False, they decrease salinity because they bring out a lot of sediment
At poles salinity is ________.
1. (low) or (high)
The reason is because there is ____ precipitation and ____ evaporation.
(high/low) or (low/high)
At poles, salinity is ___low___. The reason is because there is __high__ precipitation and __low__ evaporation.
At subtropical regions there is ______ precipitation, and ______ evaporation. (Deserts are found in this region)
(low/high) or (high/low)
Low/high
T/F At equator, salinity is in between, there is a balance of high precipitation and high evaporation.
true
What is the temperature of the max density of water?
4 degrees celsius
How does the density of water change with freezing temp?
At 0 degrees ice forms and density decreases however as water cools, it gets denser only up to about 4 degrees celsius, after that density starts decreasing as ice is forming.
Why does ice float?
water is denser than ice and ice is less dense because molecules are spread further apart.
How do we know the Mediterranean Sea starts drying up 6 MYA?
It dries up due to evaporation (latitude) and we know this because layers of solid rock salt are found.
At around which latitude is the Mediterranean Sea found? Is it dry/humid? What about salinity (higher/lower than average)?
The MS is at about 35 degrees latitude which means it is very dry. Salinity is about 38 PPT, which is above average
T/F Deserts only occur on land.
False they occur on land as well as oceans
Where do Salt ions come from? (3 main sources)
- Continental rocks (travel to ocean by rivers. The erosion of rocks push sediment into the bottom of ocean (sodium)
- Volcanic Activity- chloride comes from volcanic eruptions both on land and under oceans
- Hydrothermal Vents- stuff that comes out can provide oceans with salts
What is the density structure of oceans?
0-200m we have the surface layer (about 2% of ocean)
Least Dense
200- 1000m we have the Thermocline (about 18 percent of ocean)
1000- 4000m we have the Deep Zone (about 80% of ocean)
Most Dense
- we have an exception of hydrothermal vents in the deep zone because they are extremely hot and less dense.
Briefly explain the surface layer.
(0-200m depth) and it is a warm mixed layer (current/waves) driven by wind.
Briefly explain the thermocline’s temperature.
(200-1000m depth) and it has a rapid temperature decrease with depth
Briefly explain the Deep Zone.
(1000-4000m depth) and it is very dark, cold, salty therefore the densest (avg temp- 4 degrees C)
Do we have a thermocline at polar regions?
no, its oceans are already very cold and they dont get sun for about 6 months of the year. We mainly have cold, salty water sinking all the time.
Cohesion only exists in which two forms?
water and ice
What is water’s sound transmission?
Very fast (1500m/second)
What drives the weather?
Sun (heat) Oceans (coastal climates) - sun heats up oceans, oceans release heat into atmosphere Atmosphere Rotation of Earth Uneven Solar Absorption The Hydrologic Cycle (water cycle)
What process is evaporation (what two phase changes)
Turns a liquid to a gas ex: ocean water turning to water vapor
In evaporation, heat is _______. In condensation heat is __________.
(absorbed/released) or (released/absorbed)?
In evaporation, heat is absorbed. In condensation heat is released.
T/F evaporation is a cooling phase change
true, example: it is a way oceans cool off
What process is condensation? (2 phase changes)
gas to liquid ex: water vapor to rain
Why is solar radiation the strongest around equatorial regions?
earth’s surface faces incoming radiation at a right angle, a lot of energy absorbed at equatorial region
Where is solar radiation most/least absorbed?
Solar radiation is strongest at equatorial regions because the energy is absorbed by oceans and solar radiation is weakest at polar regions because the energy is simply reflected by ice and snow
Explain the angle of the sun in equatorial, mid lat. and polar regions
at equator, the sun is directly on top (high angle small area)
at mid-latitudes, sun is at an angle
at polar regions, sun is at a low angle yet shines on a larger area
What two factors distribute heat and circulation around earth?
- atmospheric circulation
2. ocean currents
Which event breaks H bonds?
Evaporation or condensation?
Evaporation, liquid has some H bonds connected but once it turns to gas, H bonds are broken and elements are “zooming around”
Hurricanes need _____ water to function
warm, cold, mild
warm
What is the most abundant gas in our atmosphere?
Nitrogen
What is the composition of the atmosphere? (in order of abundance)
78% of earth’s atmosphere is Nitrogen
21% of earth’s atmosphere is oxygen
0.9% of earth’s atmosphere is argon
0.04% of earth’s atmosphere is Carbon dioxide
What is the lowest region in the atmosphere (above lithosphere)?
Troposphere (lower 12 km)- weather takes place here
T/F Temperature increases with altitude.
False, it decreases
In which layer does does convection take place?
troposphere
What is convection?
in the atmosphere: warm air rises and cold air sinks
Explain the features of warm/cold air.
warm air → less dense → rises (expands)
cold air → more dense → sinks (contracting)
explain how pressure works
low pressure is light and column of air rises
high pressure is heavy and column of air sinks
Air always moves from high to low
What is pressure defined as?
the weight the atmosphere exerts on an object.
Around what regions is air pressure low?
around equatorial regions- air is rising due to evaporation of oceans
Which type of air pressure system affects California? what is it called?
High pressure system called the North Pacific High
Describe weather/ air conditions at equator
The equator is mostly oceans so the air is very warm and humid. Humidity comes from evaporated ocean water and the air rises meaning it is less dense.
Is the equator affected by low/high pressure?
low pressure, air expands, cools and as it cools, water vapor turns into rain
Is the California Current warm enough to create hurricanes?
no, it is a current that comes from Alaska and travels south towards the coast of California
Briefly explain the Hadley cell
It is a convection cell where air rises at the equator and by around 30 degrees latitude, sinks.
T/F All weather starts at Hadley cell
true
Around which areas are deserts formed?
subtropical zones ( - about 30 degrees)
Which lat. regions are high pressure? which are low?
polar regions, 30 degrees latitude= high pressure
equator, 60 degrees latitude= low pressure
What causes the Coriolis Effect?
the rotation of the earth
What causes objects to “veer off” to the right in the N hemisphere and left in the S hemisphere?
According to Coriolis Effect, due to the rotation of the earth, objects or in this case, wind in the N hemisphere will veer off slightly to the right and in the S hemisphere, they will veer off slightly to the left.
what region is least affected by Coriolis?
the equator
Where is the Coriolis the strongest?
at the poles
What is atmospheric circulation caused by?
Earth’s rotation
Where air is ______ we find the low pressure areas.
rising, sinking
rising
In _______ pressure regions, we find most of our rainforests.
high, low
low
In _____ pressure regions, we have clear skies and little rainfall.
high, low
high
T/F we find most (land/hot) desert regions in high pressure regions.
true
The earth’s surface rotates ________ at the equator than poles
faster, slower
faster because earth’s surface travels a greater distance (than poles) for the same amount of time so it must be going faster.
The Trade winds (Easterlies) flow _____ to ______ towards the _________.
west, east, equator
The Trade winds (Easterlies) flow east to west towards the equator.
T/F Prevailing winds originate at the subtropical high pressure (about 30 degrees)
true
The Westerlies flow ____ to _____ towards the _____.
east, west, poles
The Westerlies flow __west__ to east towards the poles.
What is a hurricane defined as?
A storm forming @ tropical regions and spinning very fast counter clockwise.
Hurricanes occur from what latitude regions? Does this mainly occur in the N or S hemisphere?
5-25 degree lat. in the N hemisphere
Does the equator have hurricanes?
No, all they have is low pressure because they have no Coriolis
What is the difference between a hurricane a typhoon and a cyclone?
None, they are all the same but their location is different.
Hurricane= Atlantic, NE pacific (USA)
Cyclone= South Pacific, Indian Ocean
Typhoon= NW pacific
In the N hemisphere, hurricanes rotate _____. In the S hemisphere, they rotate ______.
counterclockwise, clockwise.
In the N hemisphere, hurricanes rotate counterclockwise. In the S hemisphere, they rotate clockwise.
What is the difference between cyclone and anticyclone?
A cyclone is a low pressure system and an anti-cyclone is a high pressure system. Wind travels clockwise around anti-cyclone and counter-clockwise in a cyclone.
Hurricane Irma had a huge rotating low pressure system so another name for it is….
cyclone
During which season do MOST hurricanes occur? Why?
Fall and some of summer because during summer, oceans are heating up and their energy releases after summertime. (specifically june-november)
What is the “source of power” for hurricanes?
Warm waters
Why aren’t hurricanes common in the S hemisphere?
Because they have a huge ice continent (Antartica) making the S hemisphere too cold for hurricanes.
Where do hurricanes end? Why?
they dissipate on land because the storm has been cut off from source.
T/F The eye is the strongest part of the hurricane
false, it is very calm and has no winds
Why is the eye of the hurricane unaffected?
due to the rotation of the hurricane, air in center sinks, dries up and forms a H pressure system inside stormy (low pressure) conditions.
What are the conditions for hurricanes? What makes a hurricane?
- winds need to be around 120km/hr (+) or 78 mph (+)
- seawater has to be warm about 26 degrees celsius (80 degrees F)
- Warm, humid, moist air (usually around 0-30 degrees)
- Weak wind shear (defined as wind moving along surface) has to be fairly low.
What is a storm surge?
flood of rising water (associated with low pressure/hurricanes). Oceans are coming into land and flooding everything.
Why was Hurricane Katrina deadly?
New Orleans is very flat, below sea level because its on a passive margin so 80 percent of New Orleans was flooded and under water.
T/F Weak Sheer is also known as having High Pressure “above” the storm
True, it a key feature in keeping the storm alive.
What is the most intense part of the hurricane? (near the eye)
The eye wall all the way out to the right quadrant
What is the greenhouse effect?
solar radiation comes in, it is absorbed by earth and the atmosphere will absorb infra-red radiation from earth.
What are the most abundant greenhouse gases? (list in order of abundance)
h2O, CO2, CH4, N2O, O3
What do temperature records indicate?
Temperature has increased .85% (anthropogenic, caused by humans)
What do carbon dioxide records indicate?
Human activities are causing CO2 and other greenhouse gases to increase. CO2 increased by 40%
Do temp and CO2 correlate with each other?
yes, rising co2 = rising temperature
What are some changes with increased warming?
- melting of ice (especially in the North)
- Steady but small rise in sea level
- Severe weather
- Extinctions
Northern Hemisphere has more ______ which means low heat capacity and has had a natural ______ trend since the death of the dinosaurs
(land/oceans) or (warming/cooling)
Northern Hemisphere has more land which means low heat capacity and has had a natural cooling trend since the death of the dinosaurs
T/F in the last 2 million years, Ice age is followed by global warming.
True
T/F Today we have rapid warming due to carbon emissions from industries.
True
What is going on in the Arctic?
10% ice loss per decade so the Arctic sea is shrinking.
T/F If Ice melts, the oceans will warm up slower
False, they will heat up faster because they are losing the reflective surface caused by the ice.
What is occurring at Greenland?
ice is melting and creating “lakes” and since water is denser than ice, it tries to sink and creates cascades going thru thick ice sheets eventually reaching the ocean.
https://www.youtube.com/watch?v=3F9FbdqGRsg
Why did the Titanic sink?
It hit an iceberg so water filled up the hull and it became denser than the ocean
What causes ocean acidification?
Acidification is caused by oceans absorbing CO2 (about 35% from atmosphere)
Seawater ph _________ with CO2
increases/decreases
Seawater ph decreases with CO2
What organisms are affected by pH?
Coccolithophores, corals, sea urchins
How are ecosystems threatened?
Organisms make their shells out of calcium carbonate, shells get eroded by CO2
_____ CO2, _______ acidic levels.
high, high) (high,low) (low, high) (low,low
__High___ CO2, ___high____ acidic levels.
T/F In the past 200 years, pH levels have gone down from an average of 8.25 to 8.14
true, the lower the pH, the more acidic it is.
What are the 2 types of currents?
Surface currents and Deep Currents.
What drives surface currents?
wind specifically, prevailing winds (easterlies/westerlies)
What drives deep currents?
Density driven.
What are the 2 types of surface currents?What are some examples of each?
Western Boundary Currents (ex: Gulf Stream)
Eastern Boundary Currents (ex: California Stream
What are the differences between WBC and EBC?
Western Boundary Currents: -warm, originate from tropics -flow to the west of an ocean basin - usually to the east of a continent like US -deflected North Eastern Boundary Currents: -cold, originate from poles - flow to the east part of an ocean basin -deflected South
In the northern hemisphere currents move _______.
Clockwise
T/F In the North, the water from ocean basins will rotate counterclockwise.
False, they will rotate clockwise
Why does ocean water rotate clockwise?
Because we are in the N hemisphere and winds always veer off to the right (in the N)
what are ocean gyres?
a large system of circular ocean currents formed by wind patterns and Earth’s rotation
In the middle of ocean gyres, salinity is really _____.
low/high
high
Why is the West Pacific really warm?
because trade winds are veered off to the right (warm water is an indicator of hurricanes)
Do currents control coastal climate?If yes how?
Cold currents give dry, cool weather with little rain
Warm Currents give humid warm weather with more rain
What can we say about the Gulf Stream?
It is a Western Boundary current because it is in the west of an ocean basin and moves clockwise
What is Ekman Transport?
Seawater moves 90 degrees to the right of wind (because of Coriolis) and Ekman flow eventually leads to up/down welling
(wind driven vertical circulation)
What is upwelling?
- cold, deep nutrient-rich water rises to surface due to Ekman flow.
- There is an abundance of sealife
- deep waters come up because the winds veered water off
- upwelling usually occurs in the W side of continents
What are El Nino conditions?
- comes along winter
- pushes warm water to americas
- trade winds weaken/reverse
- Causes Low pressure rain in the Americas
- Causes High pressure in the West Pacific
- Thermocline lowers and there is no up/downwelling
In normal conditions, thermocline _____. In El Nino conditions, the thermocline ______.
(lowers/rises)
Rises, lowers
What are the 2 sources for deep currents?
They are driven by differences on density and salinity/temp.
What is the difference between wind waves, tsunamis and tides?
Wind waves= driven by weather
tsunami= driven by earthquake under ocean
tides= driven by moon
What produces small beach waves?
The winds
What is the wave base?
depth to which wave can be felt
What is the top of the wave called?
crest
What is the bottom of the wave?
trough
The wave length is….
the distance between Crests
Height of wave is measured by
vertical distance from crest to trough
Wave period is….
the time it takes for a wave to pass a fixed point
What is the formula for wave base?
Depth=1/2 Length (it can be felt up to half of the wave under water)
What are shallow water waves?
wave drags on bottom (seafloor)
- huge wavelength
- all tsunamis and tides are shallow water waves that move through entire depth (bottom of seafloor)
When do waves break?:
When the wave feels the bottom/seafloor. When the height increases, velocity decreases, wavelength shortens.
When the circular orbital motion is disrupted against the seafloor
