Marine PhysicsMarine PhysicsChapters 6-9Chapters 6-9
JUST COPY WHAT JUST COPY WHAT IS IS
UNDERLINED!!!!!!UNDERLINED!!!!!!
Influence of Currents on Climate
Pgs.
Because of the area and thermal properties of the ocean it dramatically influences global weather and climate patterns.
Currents moderate climates- without the currents moving heat, the world’s climates would be more extreme.
Gulf Stream One of the deepest
surface currents-
carries heat Powerful, warm, swift Starts at the Gulf of Mexico, crosses the Atlantic Ocean Influences the east coast of N. America and the west
coast of Europe Moves warm air from
over the Gulf Stream inland Florida and N. Europe-
milder winters
California Current
S. California- mild climate due to the moderating effects of the Pacific Ocean The southerly current along the Calif. coast brings
cool water from the north, keeping it cooler than it normally would be in the summer
Factors that Affect Direction and Patterns of
Major Ocean Surface Currents
Pgs 9-3 to 9-5
#1 Wind Transfers energy to the water it blows across
by the force of friction on the water’s surface Causes both surface currents and waves Ekman Transport/Spiral= Current moves to
the right of the Wind at a 45 degree angle Major wind belts:
Trade winds Westerlies Polar Easterlies
#2 Land Masses interrupt the flow of ocean currents creating
closed circular current systems called gyres. Forces currents to turn
#3 Coriolis Effect influences the wind by giving it a circular flow
pattern the air deflects toward the right in the Northern
Hemisphere and toward the left in the Southern Hemisphere- same with currents
Christopher Columbus reached the new world thanks to the Coriolis effect Note: If the Earth did not rotate and remained
stationary, the atmosphere would circulate between the poles (high pressure areas) and the equator (a low pressure area) in a simple back-and-forth pattern. But because the Earth rotates, circulating air is deflected.
#4 Temperature
Convection currents Vertical movement of currents caused by
temperature differences Temperature divides layers of water Deep sea vs. surface currents
Cause of the Coriolis Effect
Earth’s rotation- adds an apparent sideways motion to objects moving over the Earth’s surface.
Pilots need to correct their flight path based on the earth rotating under the airplane, which is the Coriolis effect.
Tides
Pgs 10-3 to 10-24
What are Tides?
Daily variations in the ocean’s level The mean average tide
occurs later each day by 50 min
HighLow =6 hours 13 min.
HighHigh=12 hours 25 min.
most noticeable at the shore, but affect the entire ocean.
Cause of Tides Result from the gravitational pull of the moon, and,
to a lesser degree, the sun Earth is not a perfect sphere Time of the month, Season, Coriolis Effect Shape of the ocean basin
Large, wide basins have smaller tidal ranges Narrow, shallow basins have larger tidal rangesWhere is the largest tidal range in the world? Bay of
Fundy
Spring and Neap Tides Spring tides: occur during the full moon and new
moon (they do not have anything to do with the season Spring)
occur when the Earth, the Sun, and the Moon are in a line- every 2 weeks
high tides are very high and the low tides are very low
especially strong tides
Spring Tide
Neap tides occur during quarter moon phases occur when the gravitational forces of the Moon
and the Sun are perpendicular to one another (with respect to the Earth).
results in a smaller difference between high and low tides
especially weak tides
Neap Tide
Tidal Patterns & Currents
pgs 10-21 to 10-24
Tidal Pattern Diurnal tide
Single high and low tide daily
Location: Gulf of Mexico
Semidiurnal Tide Two “equal” high and
low tides Location: east coast of
U.S.
Mixed Tide Two unequal high and
low tides Location: Pacific coast
of U.S.
Coastal Tidal Currents
Flood current- water rushes into a bay/river with an incoming tide
Ebb current- water drains out of a bay /river because a low tide is approaching
High slack water- peak of high tide (no currents) Low slack water- peak of low tide
Waves
Parts of a Wave (draw figure)
frequency=
1/period
wave speed=
wavelength/
period
Types of Waves
Tidal Bores- wall of water that moves up certain low-lying rivers due to an incoming tide (tidal wave)
Shallow water- touch the ocean floor which interfers with the wave’s orbital motion (controlled by water depth, ex: tsunami)
Deep water- no interference with ocean bottom (wind generated, open ocean and controlled by wave length)
Rogue
Types of Breakers
Spilling- turbulent mass of air and water that runs down the front slope of the wave as it breaks from a gradual beach slope
Plunging- curling crest that moves over an air pocket from steep beach slope (best surfing)
Surging- wave energy is compressed into a shorter distance from an abrupt beach slope
What factor does not affect deepwater wave production?
A. Wind speed
B. Pull of moon
C. Fetch (distance over which wind blows)
D. Duration of the wind blowing
Answer is : B
Shallow water waves can be tsunamis or tide waves
Whereas deep water waves are solely caused by the fetch, wind speed and duration
Movement of Water in a Wave
A wave is the transmission of energy through matter.
•As the wave approaches, individual particles of water move in circular patterns as the wave’s energy moves through the water•Orbital motion
Tsunamis Sometimes reaching heights of 40 meters
(120 ft.) or more, tsunamis are the most dramatic and destructive of waves.
Seismic Sea waves
Cause of Tsunamis A tsunami results from
sudden water displacement caused by: Landslide Iceberg falling into the
sea from a glacier Undersea volcanoes Earthquake Also called tidal waves Shallow water waves,
fast moving
Hurricanes
Hurricanes generally form at the tail of the arrow and typically track following the arrow to its arrowhead.
Hurricanes form and intensify over oceanic regions. They require sea-surface temperatures of at least 26°C (80°F) and the influence of the earth’s rotation to initiate a spinning circulation (Coriolis effect).
The Atlantic hurricane season is from June 1 to November 30, but most hurricanes occur during the fall months. The Eastern Pacific hurricane season is from May 15 to November 30.
Day 2: Chapter 6 in book1. Bellwork: Read pgs. 180-181
Give 5 facts from reading
2. Draw figure 6.11 pg. 171 Define all terms on figure
3. Define: weather, climate, warm front, cold front, tropical cyclone, hurricane, typhoon, cyclone, eye of hurricane, storm surge, sea ice, ice bergs, pancake ice, ice floes, shelf ice
4. Explain how El Nino affects the Pacific Ocean surface currents? Pg. 218
5. Review Questions pg. 191 #12-14 Write out question and answer
Day 3 Thermodynamics
Open system- energy & mass flows (ex: open ocean, human body, saucepan no lid)
Closed system- heat & work can be exchanged across boundary (ex: Earth, terrarium, saucepan with lide)
Isolated- same mass, no exchange (ex: physical universe or thermos)