Phys Ocean Final 2

Front 1

How does EUC drive production

Back 1

easterlies piling water in west causes slope of thermocline rising W to E; current follows bring deep nutrients up to east

Front 2

milankovitch cycles

Back 2

long period variations in orbit:
orbital vs elliptical path
change in axial tilt
spin axis tilt (move finger)

Front 3

ENSO cause

Back 3

change in air pressure over tahiti/darwin australia, weaker trader winds

Front 4

oceanographic results of enso

Back 4

thermocline relaxes as less water piled up in west, less upwelling along coastal S. America

Front 5

atmospheric results of enso

Back 5

more warmer, spread out water, more sensible heat loss

wetter colder winters in SE US

Front 6

estuarine requirements

Back 6

semi enclosed and coastal,
connected with sea
saline

Front 7

general estuarine flow

Back 7

salt gradient driven; fresh in at surface, deep saline outl

salt wedge strongest stratification, highest flow

stronger at ebb tide

Front 8

force balance for flow equation

Back 8

turn around

Front 9

barotropic PG

Back 9

higher sea surface where river input

Front 10

baroclinic PG

Back 10

increases with depth due to salinity

Front 11

estuarine/gravitational circulation

Back 11

balanced (subtitle) barotropic and baroclinic PG

drive circulation

assumes no wind or bottom flow

Front 12

wind and flow

Back 12

surface flow moves in direction of wind; deep flow moves opposite to maintain volume

Front 13

ETM

Back 13

convergence of river flux and landward circulation

accumulation of sediment and high turbidity @ limit of salt intrusion

Front 14

balance between advection and turbulent mixing determines

Back 14

strength of vertical density gradient (board)

Front 15

length and stratification of estuary impacted by

Back 15

strength of river discharge;
stronger discharge, shorter estuary, greater stratification

Front 16

coriolis causes

Back 16

outflow to deflect to right; can add or subtract from bay

Wind to N (CB) ekman transport out and high water at N end of bay

Front 17

cold pool

Back 17

is there year round; isolated by summer stratification

Front 18

WBC

Back 18

advective dominance – high velocity, unstable, sheds eddies (warm core rings)

Front 19

warm core rings

Back 19

form (from instability) where GS separates from shelf (CH);

interact with shelf and help flush it

Front 20

WBC w/out slope sea

Back 20

pump deep water onto shelf, colder in florida rules production

Hint 20

warmer in AA, (CCDW) causes basal melt where polynyas form

Front 21

AACC against continent

Back 21

greatest basal melt

Front 22

EBC

Back 22

wind driving upwelling drives production at surface (WBC has production at bottom where water pumped over in absence of slope sea)

Front 23

THC Basics

Back 23

* heat lost from ocean at poles, cold water sinks and moves equatorward
* heat input at equator, cold water warms and moves poleward

Front 24

THC Basic Pathway

Back 24

* upwells and returns in indian
* upwells and returns in mid lat pacific across northern Australia (return stream joins indian ocean stream)

Front 25

Cross Section of Atlantic, top to bottom

Back 25

* NACW, AAIW, NADW, MIW NABW East, AADW AABW west

Front 26

dense water forms by

Back 26

* removal of heat
* ice formation
* evaporation

Front 27

* Source/Formation Region:

Back 27

* area of ocean where water mass acquires its characteristic properties

Front 28

* Conservation property

Back 28

* (apply only below ocean surface mixed layer ~1000m)
*

Front 29

* Water type:

Back 29

* body of water with a common formation history, having its origin in a particular region, occupy finite volume (point in TS space) may not exist (big average)

Front 30

* Source water type

Back 30

* water type that corresponds closely to parties of water mass in source region.

Front 31

* Water mass:

Back 31

* body of water with common formation history, origin in particular region

Front 32

convection

Back 32

* deep and bottom waters

Front 33

subduction

Back 33

* mode and intermediate waters

Front 34

subsurface mixing

Back 34

* circumpolar deep water

Front 35

ocean ventilation

Back 35

* where deep water acquire’s characteristics
*

Front 36

consolidation

Back 36

* mixing within mater mass; reduces standard deviation without changing mass (reduces TS variability)

Front 37

mixing

Back 37

* between water masses; new combinations; identify contribute water masses and determine relative scale (happens through double diffusion, molecular level)

Front 38

absorption

Back 38

* ater mass disasters by mixing with another; Med into NADW

Front 39

transformation

Back 39

* change to another water mass by subsurface mixing CDW

Front 40

NADW formed

Back 40

* in Labrador (little), Greenland, Norwegian Sea
* 2–4ºC; 34.9 – 35 psu

Front 41

no bottom water formation in pacific?

Back 41

not salty enough

Front 42

* trong MOC mixes with relatively fresh Arctic,

Back 42

* keeping salinity relatively high; allows for formation of NADW
* freshening of arctic will weaken MOC

Front 43

* Climate feedback MOC

Back 43

* without redistribution of heat by slower circulation, polar water colder, ice grows and becomes saltier

Front 44

AABW more dense than NADW because

Back 44

* more dense because ‘less entrainment' with surface
*

Front 45

polynya defn and formation

Back 45

* latent heat formation: ice formed and wind blows away repeatedly
* sensible heat formation: ice melts from below (Antarctic water) upwelling

Front 46

* Polynyas form and freeze

Back 46

forming AABW
* this collections on antarctic shelf and eventually spills into deep water
* this foredeepend shelf is closer to land because ice sitting on it
* .4–1ºC; 34.6 – 34.9 psu

Front 47

MIW

Back 47

* Mediterranean net evaporation, tongue flows over Gibraltar strait
* 5–10ºC; 35.5–35.9 psu
* return path of THC; important source of salinity for NADW formation
*

Front 48

theory for deep circulation principles

Back 48

1. Supply of cold dense waters by itself doesn’t drive deep circulation; need sinking near poles to be balanced by rising water
2. Permanent thermocline depth ~ constant. Net input of heat at equator, so thermocline can only remain constant if there is a source of cold water from below (entrainment and mixing).
3. Turbulent mixing and not density differences drives the deep circulation. This requires overturning (mixing) hence MOC

Front 49

theory for deep circulation details

Back 49

* stratification up (input heat and freshwater), speed down
* NH moving toward equator increases positive vorticity
* So friction can only balance planetary vorticity of an equatorward flow along WBC
*

Front 50

MOC moves heat received across equator so

Back 50

* ~ flux of 20 Sv
* 35% of insolation received at 40ºN is put into North Atlantic through conversation from warm surface to cold NADW
* so 5º colder in NA if no MOC; slowing of ^ could cause ice to reform in Norway
*

Front 51

Water mass general characteristics

Back 51

* NA: open to north, limited seasonal sea ice, freshwater sources (rivers)
*

Front 52

* NADW, GSW, LSW (Labrador Sea Water), MSW STO

Back 52

* high salinity, low temp, high O2

Front 53

* AAIW SI

Back 53

* low salinity, high oxygen

Front 54

* AABW STO

Back 54

* high salinity, low temperature, average O2

Front 55

* Subtropical underwater:

Back 55

* low oxygen; consumed though respiration, less mixing

Front 56

* AABW blocked

Back 56

* on eastern side blocked by Walvis Ridge

Front 57

* Catabatic winds

Back 57

* in AA drives off ice and forms polynyas

Front 58

* TS Distribution for world oceans; most is 34.6 ppt and ~ 1.5ºC (potential)

Back 58

* Atlantic, saltiest and mid temp
* Indian, less salty and cooler
* Pacific, fresh and warmer

Front 59

AACC
* formed of

Back 59

* 40/55 cm/s; 40–45 Km wide; locations?
* transport through drakes passage ~ 120 Sv
* boundary between mid/high latitude waters?

Front 60

* AABW moves

Back 60

* clockwise around S pole between 70 N and 70 S

Front 61

intermediate/node waters

Back 61

* subducted @ polar front
* Winds W to E; ekman transport north

Front 62

shelfs and AABW

Back 62

* High Salinity Shelf Water precursor of AABW
* Ice Shelf Water formed under ice shelf (high pressure allows it to be water below it’s freezing point)
* Circumpolar Deep Water cools and freshens all oceans as they enter

Front 63

pacific basin

Back 63

* composed of many little basins made of pacific common water; mix of everything
* south west pacific about as from from source waters as you can get; oldest and O2 depleted
*

Front 64

Internal Osciallation formula

Back 64

combined coriolis parameters

Front 65

internal oscillation

Back 65

ocean impulsively started (cold fronts)
no slope/pressure
motion in circle

Front 66

geostrophic flow

Back 66

flow is balance between coriolis and pressure

pressure directs flow along pressure gradient from high to low;
coriolis acts opposite pulls flow R of Low pressure ALONG CONSTANT PRESSURE/SSH

Front 67

density decreases west to east NH

Back 67

dividing by smaller, speed increases north as move up water column

Front 68

pressure increases west to east NH

Back 68

flow north; greater increase greater speed

Front 69

necessary condition for observed gulf stream and implications

Back 69

it must be a meter higher over 50 km; if it slows slope will change and it will flood here

Front 70

potential density

Back 70

density of water moved adiabatically to ocean surf; so effects of compressibility removed

Front 71

specific volume

Back 71

1/density

Front 72

specific volume anomoly

Back 72

difference in specific volume of sample and open ocean (no need for potential density)

Front 73

dynamic height

Back 73

measure of potential energy change between two pressure levels

measuring the energy (divide by gravity for height) required to maintain the pressure between two surfaces based on density fluctuations. More dense, less height/energy

Front 74

dynamic height anamoly

Back 74

change in dynamic heights between two stations at same pressure is proportional to horizontal pressure change.

subtract standard ocean (1/density at S 35, T 0, P same)

Front 75

hydrostatic and rearrangment formula

Back 75

dP/dz = –grho

alpha (1/rho) dP = –gdz

–gdz = D ynamic height (integrate to solve)

Front 76

horizontal and vertical force balance in ocean

Back 76

horizontal geostrophic: pressure vs coriolis
vertical hydrostatic: gravity * desnity (weight) down by vertical pressure gradient up

Front 77

quasi geostrophic

Back 77

allowing small changes in pressure and flow

Front 78

turbulent friction

Back 78

10 – 100 meters ekman force matters
mixed layer wind blowing over surface exterts tangential force (surface stress, wind acts parallel to ocean surface)

Front 79

wind causes water to move

Back 79

at linearly decreasing speed with depth

Front 80

wind forcing with coriolis

Back 80

surface current 45degrees to right of wind in NH

ekman spiral;
Newton's third law (equal and opposite force) moving down water column, speed slows a deflects a little more to right

Front 81

2 forces acting on vertically integrated column

Back 81

wind and coriolis; net transport in friction layer 90 degrees to right of wind; just like 90 degrees right of pressure gradient

Front 82

winds blow

Back 82

along coast, upwelling because water transport is offshore

Front 83

upwelling with two density layers

Back 83

north wind, transport offshore
establishes a pressure gradient (higher where more water offshore)
net flow now north, same as wind (because of geostrophic)

more dense water fills in where water lost at coast. slowly reverses pressure gradient and thus transport.

Front 84

bottom friction

Back 84

pressure constant but water slows. thus coriolis must be weakening. so transport shifts to the direction of the pressure gradient (low to west, flow to west)

transport is thus left of water above it.

Front 85

ekman pumping

Back 85

wind is blowing on one spot; because of coriolis in N there will be more transport to the right of this spot and downwelling; less to left and upwelling.

Front 86

equator out wind direction

Back 86

east between 30 and 0: trades
west between 60 and 30: westerlies
east between 90 and 60: polar easterlies

Front 87

wind cells

Back 87

NH
Hadley 0/30 counterclockwise
Ferrel 30/60 clockwise
Polar 60/90 counterclockwise

Front 88

circulation caused by wind pattern

Back 88

trades and westerlies; ekman push water into center gyrating fashion. sea level rises in center, thermocline/pycnocline descends (density decreases, faster)

Front 89

vorticity

Back 89

instrinsic spin of fluid
zeta = chaning N/S velocity as EW direction – chging speed in EW as changing NS direction

Front 90

planetary vorticity

Back 90

f = 2 thingy sin (lat)
coriolis

Front 91

potential vorticity

Back 91

total spin of fluid column divided by height

conserved following flow if no friction or forcing
(so if f changes with latitude zeta or H must)

Front 92

wind adds ______ vorticity because

Back 92

negative, clockwise ekman (WE (+) direction, flow NS (–) +*– = –); – (NS direction, Flow E to W so –– +)

Front 93

eastern boundary vorticity dynamics

Back 93

north; negative vorticity balanced as you decrease latitude and decrease f
south; negative vorticity balanced by continent friction

Front 94

western boundary vorticity dynamics

Back 94

south; negative vorticity balanced decrease in latitude

north; negative vorticity increases as you increase latitude; unbalanced

Hint 94

result because gyre doesn't move: negative vorticity expressed as increase in speed along boundary (western intensification) that results in enough friction to balance vorticity

Front 95

conservation of PV

Back 95

conserved following flow if no friction or forcing (because it's energy)

we assume isobaric (no depth change) when working with it so change in latitude must correspond to change in relative vorticity

Front 96

hydrostatic pressure

Back 96

vertical force opposing gravity
pressure force change in w/ depth balances weight of fluid (P = rho*g*depth)

Front 97

horizontal pressure gradient

Back 97

change in accel = –gS(difference in height)/L (distance separating)

Front 98

horizontal density gradient

Back 98

accel = –g (rho 2 – rho 1) *h/rhoL

Front 99

coriolis vs centrifugal

Back 99

while in motion earth moves you right in coriolis
spinning earth throws anything away from axis

Front 100

coriolis force =

Back 100

f*u
f = 2 rate of spin *sin (latitude) about 10^–4 at midlatitudes

Front 101

friction

Back 101

Fx = –K (deriv A/deriv X)

Ficks law;
diffusive flux in x direction = diffusivity (constant) *change in concentration in changing x direction

Front 102

if diffusivity flux varies in space

Back 102

take derivative of diffusive flux (a/t)
= K (second derivative of A/second derivative of x)

factor out deriv/derivX for molecular diffusivity

Front 103

turbulent vertical velocity

Back 103

change in correlation of speed fluctuations
average compass direction speeds correlated with vertical movement

higher wind speed more vertical mixing

vertical change of vertical correlation

Front 104

reynolds averaging

Back 104

to separate mean velocity (u bar) from turbulence (u prime)

Front 105

to make average flux equation

Back 105

average of each term and add 0 acceleration (boussinesq)

Front 106

reynolds number

Back 106

compares inertial forces (advective) forces to viscous (Friction) forces

Re = UL/v

when large, molecular viscosity doesn't matter

Front 107

rossby number

Back 107

compares inertial forces to coriolis

U^2/L : fU
Ro = U/Lf
small rossby means coriolis important (is in ocean)

Front 108

ekman number

Back 108

Coriolis to vertical turbulent viscosity
fU=Kh (U/H^2)

Kh/H^2f

kh = .01; matters at surface, not at depth

Front 109

geostrophic balance

Back 109

pressure gradient must balance coriolis force
it does ~ 1 m rise in sea surface over 100 km balances

fV = gS/L

solve for S using v = 1m/s and L = 100 Km (gulf)

Front 110

kinematics vs dynamics

Back 110

analysis of motion withou forces vs with forces

Front 111

newton's 1st law

Back 111

inertia; remains in motion stays in motion

Front 112

newton's 2nd law

Back 112

f = ma

in ocean, acceleration is produced by net forces

Front 113

newton's 3rd law

Back 113

if one object exerts a force on a second object, then second exerts and equal and opposite force

in ocean think about pressure gradient up and down and

Front 114

unsteady vs steady motion

Back 114

unsteady time dependent, changes with time; non zero acceleration

steady is independent of time; forces balanced; no acceleration

Front 115

4 forces interior to ocean

Back 115

gravity
pressure gradients
coriolis
friction

Front 116

brownian motion

Back 116

thermal agitation of fluid molecules

Front 117

fick's law def

Back 117

mixing proportional to spatial gradient of the property

Front 118

if _____ is being diffused the constant is called the _________

Back 118

momentum, viscosity

Front 119

Incoming heat vs outgoing heat

Back 119

all outgoing in top millimiter
incoming begins 10^–6 m more until 1 then back down

Front 120

Wien's Law

Back 120

wavelength of maximum transmission is inversely proportional to the absolute temperature

lambda max = b/k
b=cw=constant=2.9*10^6 nm * K

Front 121

Stefan Boltzmann Law

Back 121

all bodies radiate energy at a rate proportional to 4th power of absolute temp:
Qb = CsK^4
Cs = 5.6*10^–8 W/m^2 K^4

Front 122

relation between wien and stefan boltzmann

Back 122

type of wavelength emitted vs amount of energy radiated

Front 123

solar constant

Back 123

flat plate receives 1368 watts/m^2
earth receives 342 watts/m^2

Front 124

wavelengths emitted by sun

Back 124

50% visible; 10% UV remainder 40%
Max red because 5500K is sun

Front 125

less irradiance reaches surface of earth because

Back 125

absoption by atmosphere particles

Front 126

average planetary albedo

Back 126

30%

Front 127

Ice albedo feedback:

Back 127

More ice formation, greater albedo, less absorbed radiation, more cool oceans, MORE ice formation (positive feedback)

Front 128

ocean radiates vs absorbs where difference?

Back 128

400 w/m^2 emitted; half of 342 absorbed; rest is effective back radiation

effective back radiation: atmosphere traps longer wave infrared (lets through short from sun)
about 50 –75 w/M^2

Front 129

OLR

Back 129

outgoing long wave radiation decreases from equator poleward

Front 130

latent heat loss

Back 130

energy to break hydrogen bonds and evaporate; about 100W/M^2 greatest at equator and in gyres

Front 131

conservative materials have no

Back 131

sources or sinks

Front 132

absorption by gas

Back 132

UV = o3
Short infrared 02, medium infrared water, long infrared CO2

Front 133

factors affecting Qs

Back 133

height of sun
length of day
albedo
attenuation: clouds, path through atmosphere (height of sun dependent)
gas molecules, aerosols, dust

Front 134

net infrared flux depends on

Back 134

cloud thickness (thicker less heat to escape)
cloud height (clouds radiate heat towards earth as black body, high colder than low)

Front 135

relative atmospheric warming

Back 135

44 from earth 20 from sun

Front 136

molecular vs turbulent diffusion coefficeint

Back 136

1.5x10^–9 m^2/s
1x10^–2

Front 137

Reynolds number

Back 137

inertial to viscous, velocity scale x length scle / viscosity of substance

Front 138

salt equation for turbulent flow

Back 138

flow out equals in speed of flow in all directions + vertical turbulent flux change in depth * Az *change in salinity with depth (gradient

Front 139

Box Model Knudsen's RElationship

Back 139

Vi+R+P=E+Vo
R+P–E = x
Vo–Vi = X

with conservation of salt

ViSiPi = VoSoPo
Vi=X(So/Si–So)
Vo=X(Si/Si–So)

Front 140

Residence Time

Back 140

Tres=Vol/Flux In

Front 141

SST Up

Back 141

Qb down; Qe down; Qh up

Front 142

decreased relative humidity

Back 142

Qe up; Qb up

Front 143

increased wind speed

Back 143

Qe up; Qh up

Front 144

decreased air temperature

Back 144

Qh up; Qb up

Front 145

effective back radiation is difference between

Back 145

long way energy emitted from sea surface minus long wave energy received from atmosphere

Front 146

night/day b radiation

Back 146

cloud cover at night, frost results from radiative cooling whereas on clear nights it does not

Front 147

Qb

Back 147

net rate of heat loss by sea as long wave radiation to the atmosphere and space

Front 148

decreased air/water temp difference

Back 148

Qh down Qb down (less humidity)

Front 149

thermal vs salinity diffusivity

Back 149

thermal faster 1.5x10^–7
salinity 1.5 *10^–9

Front 150

increase/decrease in SST

increase/decrease AirT

Back 150

increase/decrease in rel humidity
decrease/increase in "

Front 151

avg langley/day over course of year

Back 151

350