exam 1 Flashcards
We can learn about the ocean using data collected by satellites in space.
True
Early Polynesians only traveled within sight of land.
False
traveled as early as 1100 B.C.
1 km = 100 m
Flase
Scientific method
Curiosity, observation and measurement, hypothesis, Experimentation, observation, models, and theory
deepest part of the ocean
Mariana trench located in pacific ocean 6.85 miles Trieste (us navy) 1960 Deep sea challenger
The ocean provides how much of the oxygen we breathe?
70% of oxygen
What is the freezing point of pure water in degrees Celsius?
O
What percent of the Earth is covered by the ocean?
70.8%
subversives and ROVs
Trieste (US navy)
Deep sea challenger
Jason
Alvin
nebular hypothesis
all bodies in our solar system formed from a huge cloud of gas and dust mainly composed of hydrogen
big bang theory
space and time started when
all matter and energy in the universe expanded
from a single point in a cosmic explosion.
• Universe still expanding – measured
with Hubble Space Telescope.
• Approximately 14 billion years old.
Formation of Earths atomsphere
initial atmosphere blown away by solar wind
second atmosphere produced by outgassing
formation of oceans
outgassing
earth cooled water vapor condensed and rained down on Earth
4 billion years ago
early life
3.5 billion years old
hypothesis include
1. Life originated around hydrothermal vents in deep
ocean.
2. Life originated deep below Earth’s surface.
3. Life may have arrived on comets.
Stanley Miller’s experiment
1952 development of life on Earth. Exposed a mixture of gases and water to ultraviolet light and sparks. Organic molecules (amino acids) formed. Showed that vast amounts of organic molecules could have been formed in Earth’s early Oceans.
Heterotrophs
First forms of life.
External food supply.
Energy from breaking down organic molecules in
primordial soup.
Autotrophs
Make their own food
evolved later than heterotrophs
Anaerobic- bacteria (chemosynthesis)
Photosynthetic
autotrophs: Chlorophyll captures
solar energy – led to aerobic (use oxygen)
organisms and extinction of many anaerobic
organisms
Great oxidation Event
2 billion years ago
photosynthetic bacteria releases oxygen to atmosphere
oxidized rocks
ozone builds up
protected earth from UV radiation
Cyanobacteria- earliest aerobic autotrophs
Water: Electrical Polarity
Both hydrogen atoms are on the same side of the oxygen atom.
Slight negative charge on the side of oxygen atoms
slight positive charge on the side of hydrogen atoms
Charge seperation = electrical polarity
arranged according to polarity
dipolar
water
has a positively charged end and a negative end
hydrogen bonds
attraction between hydrogen and oxygen atoms
weaker than covalent bonds with a single water molecule
strong enough to cause cohesion
Cohesion
causes water to stick to itself and have surface tension
water thermal properties
Add or remove energy
To change the state of a substance, the forces
that cause molecules to be attracted to each
other must be broken.
Van der Waals forces
Calorie
amount of heat required to raise the
temperature of 1 g of liquid water by 1 ºC.
Heat
total energy of molecules
Heat may be generated through chemical reactions
such as combustion, from friction or from radioactive
decay.
Temperature
measure of the average
kinetic (moving) energy of the molecules that
make up a substance.
Temperature changes on the addition or removal of
heat energy to a substance.
Solid (ice)
water has rigid structure and does
not flow. Intermolecular bonds are constantly
breaking and reforming as molecules vibrate, but
molecules remain in fixed positions.
Liquid (water)
Water molecules still interact with
one another but have enough kinetic energy to
break bonds and flow.
Gas (water vapor)
molecules have enough
kinetic energy to fully overcome intermolecular
bonds and do not interact except during collisions.
Heat Capacity
amount of heat required to raise
the temperature of 1 gram of any substance 1o C.
Water has a high heat capacity because of hydrogen bonds
rocks and metals have a low heat capacity
Latent heat of melting
energy required to
break intermolecular bonds between ice
molecules to form water; 80 cal g-1
Latent heat of vaporization
energy required
to be added at the boiling point of water to break
the intermolecular bonds and change the state
from a liquid to vapor; 540 cal g-1
identical to the
latent heat of condensation.
Latent heat of condensation
occurs when
water vapor cools sufficiently to condense;
condensation releases energy which can power
thunderstorms and hurricanes.
Latent heat of freezing
Heat released when
liquid water freezes
identical to latent heat of melting
Latent heat of evaporization
conversion of liquid to
gas below its boiling point is called evaporation
Global thermostatic effects
moderate changes in
temperature and drive Earth’s climate, making life possible.
Heat energy is removed from low latitudes and
added to the heat-deficient high latitudes
Mariner- temp. of land moderated by proximity to ocean
Continental- larger fluctuations less influenced by ocean
evaporation condensation cycle
Energy from sun stored in the ocean.
Evaporation removes heat from ocean transferred to
atmosphere.
Water vapor condenses in cooler, higher air to form clouds
and precipitation which
salinity
is the ratio of the mass of dissolved
substances to the mass of the water sample
does not include fine particles in suspension or dissolved organic substances
Brackish water
where seawater mixes with freshwater (e.g. rivers, rain). Baltic Sea only 10
‰ due to inputs from rivers.
Hypersaline
occurs where mixing with the open ocean is restricted or absent and
evaporation rates are high. Red Sea has an
average salinity of 42 ‰
Decrease salinity
Precipitation (rain/snow)
Runoff (river flow)
Melting icebergs
Melting sea ice
Increase Salinity
Evaporation
Formation of sea ice
Water density
how tightly the molecules or ions of a substance are packed together
pressure, salinity, and temperature effect density
density increases as temperature increases
increases due to thermal contraction
From 4 ºC to 0 ºC water’s density decreases
Density and depth
caused a layered ocean
pycnocline- change of density with depth
thermocline- change of temperature with depth
declination
angular distance from the sun
Albedo
% of radiation reflected back into space from Earth’s surface, average about 30 %. More at high latitudes as ice more reflective.
uneven heating of the earths sun
area light covers
how much atmosphere pass through
albedo
angle of sun relative to sea surface
Troposphere
lower portion of the atmosphere, which extends to an altitude of about 12 km all weather produced here temp cools with altitude
water vapor
Water vapor decreases the density of air as
water vapor has a lower density than dry air
wind
the movement of air from high pressure to low pressure
Hadley cells
greater heating of the atmosphere over
the equator causes the air to warm and expand.
It rises and cools.
Ferrel cell
between 30 and 60 degrees
latitude. Ferrel cell not solely driven by
differences in solar heating, if they were they
would circulate in opposite direction.
Polar cell
between 60 and 90 degrees
latitude. Cold air sinks over poles
Descending columns of cool air produce high pressure
Subtropical highs – high pressure zones descending air at
latitudes of 30º north and south.
Polar highs – high pressure zones of descending air at the
poles.
Dry, clear, fair weather under highs
rising columns of low density, warm air produce low pressure
Equatorial low – low pressure zones due to rising air.
Subpolar low – low pressure zones due to rising air at latitudes
of 60º north and south.Rising air cools and cannot hold its water vapor so cloudy
weather and lots of precipitation under lows
Wind belts
Air movement from the subtropical highs to the
equatorial low constitute the trade winds.
northern hemisphere- northeast trade winds
southern hemisphere- southeast trade winds
Coriolis effect
causes moving objects on earth to follow
curved paths
caused by earths rotation to the east
northern hemisphere will move to the right
southern hemisphere will move to the left
factors that effect idealized pattern
- The seasons (produced by the tilt of the Earth’s rotational axis).
- Lower heat capacity of continental rock compared to the ocean.
- Uneven distribution of continents and ocean across the earth’s
surface
Weather
describes conditions of the atmosphere at a given time and place
climate
the long term average weather
Tropical cyclones
largest storm systems on earth large rotating mass of low pressure breaks away from the equatorial low pressure belt and grow picking up energy from the warm ocean hurricane in SA typhoons in N pacific Cyclones- Indian ocean latent heat of condensation
ocean currents
follow same patter as wind belt
transport nutrients to surface water and oxygen to deep water
surface currents
affected by the movement of air, particularly wind belts, over the surface of the ocean. Run near surface and are horizontal currents. Wind driven. above pycnocline land, friction, Coriolis effect effects direction of flow
Deep curretns
temperature and salinity
changes at surface cause high-density water to
form, which sinks.
Dense water spreads
beneath the surface, causing deep currents.
These currents have vertical motion.
Density driven.
Direct methods for measuring currents
floating device dropped into current and tracked through time. or measure a fixed position
drift meter or float meter
Indirect methods for measuring currents
Radar altimeters- satellites used to make topography maps
deep flow meters- low frequency sounds backscattered by particles in water
tilt current meter- angle of stick to determine speed
Ekman spiral ???
Fridtjof Nansen- Arctic ice moved
Walfrid Ekman- Spiral explained observation
describes speed and direction of flow of surface waters at various depth
in N surface water moves in a direction 45º
Subtropical gyers
Large, circular-moving loops of water driven by the major wind belts.
rotate clockwise N
counter clockwise S
center at latitude 30 N or S
N Atlantic gyre, S Atlantic Gyre, N Pacific Gyre, S Pacific Gyre, Indian Ocean Gyre.
Main currents of subtropical gyers
Equatorial
Western Boundary
Norther or Southern boundary
Eastern boundary
equatorial currents
trade winds set water in motion in the tropics
flow westward parallel to equator
form N or S boundary of subtropical gyres
Western boundary currents
equatorial currents meets the land on the
western side of an ocean basin.
CE deflects currents away from equator
found in western side of ocean basin (east on map)
carry water to higher latitudes
form western boundary of subtropical gyres
Norther or Southern Boundary Currents
between 30 and 60º latitude the prevailing
westerlies direct water from west to east across
an ocean basin.
Northern boundary currents – in Northern
Hemisphere comprise the northern parts of subtropical gyres.
Southern boundary currents – in Southern
Hemisphere these currents form the southern part of subtropical gyres.
Eastern boundary currents
currents are turned by the Coriolis effect and land barriers towards the equator.
Occur on the eastern boundary of ocean basins
(west on map).
Carry cool water from high latitudes towards
equator.
Form eastern boundaries of subtropical gyres.
Western intensification of subtropical gyres
Wester boundary currents don’t turn until they hit land, faster, deep, narrrow
boundary currents of all subtropical gyres are western intensified
eastern boundary currents turn before they hit land.
Equatorial concurrents
This water ‘piles’ up on the westward margins of the ocean, not turned by CE
Sea levels are 2 m higher on W side
water flows east under influence of gravity
Subpolar gyers
rotate opposite direction to subtrop. gyres in that hemisphere
fewer sub polar
Gulf stream
is a western boundary current, so it is subject to western intensification
50-75 km wide fastest currents in the ocean
warm core rings
Clockwise rotating Sargasso Sea water
1-100 km deep
Cold core rings
Counterclockwise rotating cold water which spins into the Sargasso Sea
3.5-500 km deep
Upwelling
vertical movement of water to the surface.
Water usually cold, rich in nutrients
primary production- provides food for other organisms
Equatorial upwelling common in pacific
Downwelling
vertical movement of water to deeper parts
of the ocean.
low primary productivity. carries oxygen from surface water to the deep.
surface waters move towards each other
Coastal upwelling
Wind from the N along W coast affect upwelling
Water carried to right by Ekman moves away from shore
cooling effect
Coastal downwelling
Wind from S blowing
along W coast affects
downwelling.
Water carried to right by Ekman moves toward shore
Deep ocean currents
below pycnocline
moves large volumes of water very slowly
thermohaline circulation- density differences that cause deep circulation caused by density and salinity
Temp-salinity- identify water masses salinity, temp, and density
Ocean waves
movement of air across the sea surface causes wave to form along the air-water interface
Atmospheric waves
movement of different air masses along an air-air interface.
Common along cold
fronts.
internal wave
movement of water of different densities creates internal waves.
travel along the pycnocline.
larger than surface waves
caused by turbidity currents, tides, wind stress, ships passing over the surface
progressive waves
simple waves that travel without breaking
longitudinal, transversal , or orbital
longitudinal waves
‘push-pull waves’. Particles vibrate in the same direction and back again as the energy is traveling.
transversal waves
‘side to side waves.’ Energy travels at right angles to the vibration of the particles.
generally occur in solids
orbital
waves on the surface
longitudinal and transverseal
wave height
vertical distance between crest and trough
wave length
horizontal distance between successive crest or trough
wave steepness
ratio of wave H to wave L
H/L
if it exceeds 1/7 then the wave will break
Wave period (T)
time it takes for one complete wave to pass a fixed position
Frequency (F)
the number of wave crests passing a fixed position per unit time
1/T
Circular orbital motion
Water molecules transmit the wave energy but move in a circle and end up roughly where they started
object floating have a
diameter equal to the wave height
Wave base is half of the wavelength
factors affecting wave energy
wind speed
wind duration- length of time the wind blows
fetch- distance which the wind blows in one direction
