Logistics

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Logistics
Pink Scantron Form F-1712-PAR-L Purchase 4 (n
ot 6) for the quarter
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Logistics
More Extra Office Hours Monday 1-230
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Logistics
Evaluations Instructor Valentine This is my l
ast lecture.
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Previous Lecture
Heat Balance Equator to poles Coriolis Effect C
urvature of Air, Water and Missles
Global Air Circulation Ideal and Real, ITCZ Weat
her and Storms Air Masses, Cyclones, Monsoons, an
d Hurricanes
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Lecture 8, Ocean Circulation
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Look For the Following Key Ideas
Ocean water circulates in currents.
Surface currents are caused mainly by wind, a
nd affect the uppermost 10 of the ocean.
Upwelling and downwelling describe the v
ertical movement of water masses.
The Coriolis effect modifies the course of oc
ean currents.
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Overview
Gyres Winds, Coriolis, Eckman, Gravity Currents
Boundary currents, Eddies, Upwelling Climate Eu
rope, N. America

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Ocean Currents
Ocean currents ? transfer heat from tropical
to polar regions ? influence weather and clim
ate ? distribute nutrients and scatter organis
ms
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Deep Currents
Lectures 9 and 10
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Surface Currents
? Surface currents are driven by wind
? Most wind energy is concentrated in the easter
lies and westerlies. ? The combined impact of W
ind, the Coriolis Effect, Eckman Spiral and
Gravity moves water in a circular pattern called
a gyre.
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Gyres
Wind
Coriolis
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Flow Within a Gyre
Coriolis
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Gyres
Wind
Coriolis
v
?
?
v
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Eckman Spiral
Eckman Spiral
Coriolis
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Gyres
Wind
Coriolis
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Eckman Spiral
Wind
Coriolis
Gravity
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Gyres
Wind
Coriolis
v
v
v
v
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The 5 Major Gyres
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Subdividing the Gyre
Gyres can be further subdivided into distinct
currents. The four interconnected currents in the
North Atlantic Gyre have different flow
characteristics and temperatures.
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The 5 Major Gyres
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Currents Within Gyres
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Currents Within Gyres
Western boundary currents -These are narrow,
deep, fast currents found at the western
boundaries of ocean basins. ? the Gulf Stream
? the Japan Current ? the Brazil Current ?
the Agulhas Current ? the Eastern Australian C
urrent
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Currents Within Gyres
Eastern boundary currents These currents are
cold, shallow and broad, and their boundaries are
not well defined. ? the Canary Current ? the
Benguela Current ? the California Current ?
the West Australian Current ? the Peru Current
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Currents Within Gyres
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Balancing the Water
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Countercurrents, Eddies and Undercurrents
Countercurrents flow on the surface in the
opposite direction from the main currents.
Undercurrents are countercurrents that flow bene
ath the surface current. Eddies are circular mo
vements of water that form at the interface of
adjacent currents flowing in opposite directions.
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Eddies
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Upwelling And Downwelling
Wind induced vertical circulation is vertical
movement induced by wind-driven horizontal
movement of water. Upwelling is the upward moti
on of water. This motion brings cold, nutrient
rich water towards the surface.
Downwelling is downward motion of water. It supp
lies the deeper ocean with dissolved gases.
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Equatorial Upwelling
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Coastal Upwelling/ Downwelling
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Warming Europe
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Effects of Surface Currents on Climate
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Lecture 8 Review
Gyres Winds, Coriolis, Eckman, Gravity Currents
Boundary currents, Eddies, Climate Europe, N.
America
Currents distribute heat from the equator to the
poles and have a profound effect on Earths
weather and climates.
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Lets Talk Test.
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Midterm Reminder
Next Tuesday (2/4/03)
Covers lectures 1-6
Closed Book
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Midterm Reminder
Next Tuesday (2/4/03)
Multiple Choice
60 Questions
Bring Scantron (Pink)
Bring Calculator
Lecture Demos
2 Pencils
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Midterm Reminder
Equations Provided
Information provided on the test
The mass of the ocean 1.3 1021 kg The mass o
f the atmosphere 5.14 1018 kg
The latent heat of fusion for water 80 cal/g
The latent heat of vaporization for water 540
cal/g Salinity (in ) 1.80655 Chlorinity (i
n ) Residence time Amount/Rate Heat Heat Ca
pacity temperature difference mass
Heat mass latent heat Henrys Law CP PA
a
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Calculating Residence Time
In the 1960s scientists were confused about
magnesium (Mg2) in the ocean. The quantity of
Mg2 was measured to be 1.91021g, and hadnt
changed for millions of years (indicating steady
state). The input of Mg2 from rivers was
calculated to be 1.31014 g/yr. The removal of
Mg2 as sediment-bound minerals was found to be
11013 g/yr. In the late 1960s scientists
discovered hydrothermal vents, and found they
precipitated Mg2. How much Mg2 is lost at
hydrothermal vents? What is the residence time
of Mg2 in the ocean? Based on this residence
time, do you think Mg2 is conservative?
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Calculating Residence Time
In the 1960s scientists were confused about
magnesium (Mg2) in the ocean. The quantity of
Mg2 was measured to be 1.91021g, and hadnt
changed for millions of years (indicating steady
state). The input of Mg2 from rivers was
calculated to be 1.31014 g/yr. The removal of
Mg2 as sediment-bound minerals was found to be
11013 g/yr. In the late 1960s scientists
discovered hydrothermal vents, and found they
precipitated Mg2. HOW MUCH Mg2 IS LOST AT
HYDROTHERMAL VENTS? What is the residence time of
Mg2 in the ocean? Based on this residence time,
do you think Mg2 is conservative?
Assume Steady State Sum of Sources Sum of Sinks

Inputs Outputs Addition Removal
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Calculating Residence Time
In the 1960s scientists were confused about
magnesium (Mg2) in the ocean. The quantity of
Mg2 was measured to be 1.91021g, and hadnt
changed for millions of years (indicating steady
state). The input of Mg2 from rivers was
calculated to be 1.31014 g/yr. The removal of
Mg2 as sediment-bound minerals was found to be
11013 g/yr. In the late 1960s scientists
discovered hydrothermal vents, and found they
precipitated Mg2. HOW MUCH Mg2 IS LOST AT
HYDROTHERMAL VENTS? What is the residence time
of Mg2 in the ocean? Based on this residence
time, do you think Mg2 is conservative?
Sum of Sources Sum of Sinks 1.31014 g/yr 11
013 g/yr Vent Removal Vent Removal 1.21014
g/yr
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Calculating Residence Time
In the 1960s scientists were confused about
magnesium (Mg2) in the ocean. The quantity of
Mg2 was measured to be 1.91021g, and hadnt
changed for millions of years (indicating steady
state). The input of Mg2 from rivers was
calculated to be 1.31014 g/yr. The removal of
Mg2 as sediment-bound minerals was found to be
11013 g/yr. In the late 1960s scientists
discovered hydrothermal vents, and found they
precipitated Mg2. How much Mg2 is lost at
hydrothermal vents? WHAT IS THE RESIDENCE TIME
OF Mg2 IN THE OCEAN? Based on this residence
time, do you think Mg2 is conservative?
Assume Steady State
Amount
Residence Time
Rate
Rate is the total rate of addition or removal
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Calculating Residence Time
In the 1960s scientists were confused about
magnesium (Mg2) in the ocean. The quantity of
Mg2 was measured to be 1.91021g, and hadnt
changed for millions of years (indicating steady
state). The input of Mg2 from rivers was
calculated to be 1.31014 g/yr. The removal of
Mg2 as sediment-bound minerals was found to be
11013 g/yr. In the late 1960s scientists
discovered hydrothermal vents, and found they
precipitated Mg2. How much Mg2 is lost at
hydrothermal vents? WHAT IS THE RESIDENCE TIME
OF Mg2 IN THE OCEAN? Based on this residence
time, do you think Mg2 is conservative?
Amount
Residence Time
Rate
1.91021g
Residence Time
1.21014 0.11014 g/yr
Residence Time 1.46 107 yr
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Calculating Residence Time
In the 1960s scientists were confused about
magnesium (Mg2) in the ocean. The quantity of
Mg2 was measured to be 1.91021g, and hadnt
changed for millions of years (indicating steady
state). The input of Mg2 from rivers was
calculated to be 1.31014 g/yr. The removal of
Mg2 as sediment-bound minerals was found to be
11013 g/yr. In the late 1960s scientists
discovered hydrothermal vents, and found they
precipitated Mg2. How much Mg2 is lost at
hydrothermal vents? What is the residence time
of Mg2 in the ocean? Based on this residence
time, do you think Mg2 is conservative?
Mg2 Residence Time 1.46 107 yr
Mixing time of the ocean is 1600 years
14,600,000 yr is much greater than 1600 yr
Conservative
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