final review guid Flashcards
1
Q
how do tectonic plates explain hot spots
A
an area on earth that exists over top of a mantle plume
mantle plume: in mantle where magma is hotter than surrounding magma and upwells through hot spot
NOT based on plate motion
volcanic center
oceanic islands result
2
Q
how do tectonic plates explain mid ocean ridges
A
divergence of plates, sea floor spreading (rift valley)
fractured mnt range through all ocean basins
new hot molten rock rises and fills, solidifies and then moves away
so older farther away
subduction zone at ends
3
Q
how do tectonic plates explain subduction zones
A
subduction is when two plates converge and one is denser it sudbucts into the mantle
ocean-continental (ocean is denser) subduct beneath
subduction is diving down
subduction zone is slope on plate that is going down
make trenches
cause earthquakes
4
Q
how do tectonic plates explain trenches
A
at subduction zones
dive down and make steep trench
5
Q
how do tectonic plates explain chains of volcanic islands
A
formed from hotspots
not with tectonic plate movement
just hot zone of lava from mantle plume rising up
6
Q
how do tectonic plates explain development/evolution of an atoll
A
third stage in coral reef development
as keeps to subside, eventually fully covered and coral reef is left above
get circular ring around lagoon (enclosing)
has many channels connecting lagoon to open ocean
7
Q
stages in coral reef dev
A
fringing coral
barrier reef
atoll
8
Q
fringing
A
often on volcanoes whose melting laval drips down and damages reef
initially on edge of landmass/volcanoe
- runoff from landmass (can cover reef)
not very well developed ^^, small amount of life
if land mass does not subside or sea level rise, then stop at this stage
9
Q
barrier reef
A
linear or circ, seperated from landmass by lagoon
as land mass moves down, reef stays near sealevel through upwards growth
- if cannot keep up, then die
largest is great barrier reef
10
Q
turbidity currents
A
underwater avalanche of muddy water and/or rocks over shelf to ocean floor
take large (can take boulders) and small size particles to deep ocean basin, do significant damage
carve out submarine canyons
sediment comes from shelf and move across to head of canyon
then once earthquake, to steep accumulation makes current happen
11
Q
how do turbidity currents shape continental margins?
A
they are on continental margins (at shelf)
break and rush down with gravity carving through erosion due to mass sediment motion
can shape way break looks
12
Q
how are oceans created
A
outgassing to atm
earth T got below water boiling point
so least dense volatile gases removed into atm and lots of this was water vapour so created body of water
high volcanism released lots of water vapor
also ice comets hit
13
Q
What happened during the differentiation of the Earth?
A
heavy parts have greater gravitational force and get pulled into the middle
formation into layers
14
Q
layers of earth
A
crust, mantle, core
lith, athen, meso, core (outer core, inner core)
15
Q
crust
A
granite on land
basalt in ocean
thickness varies
16
Q
mantle
A
litho athen and meso
silicate materials
17
Q
core
A
outer and inner
18
Q
lithosphere
A
rigid
floats on upper mantle (athen)
boundary btw crust and upper mantle is chemical no physical as they are both rock
19
Q
athenosphere
A
100-700 km deep
high T i smore important that high P
rocks becoming more fluid, partially fluid
under lith
20
Q
mesosphere
A
solid rock
P dominates T here
btw athen and meso is physical bounday
21
Q
outer core
A
temperature is more important here
Fe and Ni in liq
22
Q
inner core
A
P is highest
Fe and Ni in solid
23
Q
isostatic equilibrium
A
thicker is higher rising and deeper sinking
displaces weight of fluid equal to weight of entire solid
lith is floating on denser plastic athenosphere
24
Q
isostatic rebound
A
melting of ice sheets after last glacial period
causing less weight and rising of land masses
25
how isostaic equil shape features on earth
higher it rises, deeper it sinks into
crusts of ocean and land sink and balance on athen
ocean crust is denser so sits lower in mantle
thick crust of mnts, sits higher in athen then normal crust due to adjustment (roots)
26
big bang
one moment where single conetrated point exploaded to all the matter here today (15 bill yrs ago)
small earth then grow, all universe ever expanding and accelerating away from each other proportionally
space expanded at same time
27
BB timeline
1 min: particles fomred
more expansion, cooling, nuets and protons form
3mins: neuts, prots, elects combo and form H and He
3000 yrs: gravity clumps matter, algomerates = stars
10 bill yrs: solar system spinning (nebula)
dust cload shrinks, compress, flatten, rotate faster (sun)
fusion at sun core give energy radiation
proto-planets produce outer region (low T)
few mill yrs: solar system
28
hubble and humason agree with BB?
yes found evidence all galaxies moving away from each other with proportional speed and distance
1929
29
abyssal plains
flat areas of deposited sediment (suspension settling) in deep ocean floor
comes after shelf break, shelf slope and shelf rise
-from rise to basins
depends on where you are in ocean (pacific has trenches that catch sediment prior and too big in size, atlantic and indian have big abyssal plains)
30
how abyssal plains so flat?
fine sediment from suspension settling covers the irregularities there
but has peaks poking through at points (volcanic peaks: abysall hills, tablemounts, seamounts
31
seamount
rising above abyssal plains
below sea level, rise more than 1 km up
pointed top
32
table mount
flat top volcano rising above abysall plaints
33
abyssal hills or seaknolls
small, 1000 m (min amount for seamount)
very common on ocean floor
generally 200m tall
created through crust stretching when new crust at mid ocean ridge
34
why to abyssal plains deepen away from the reach
slight slope away from ridge
because ride is higher up as less dense
so sits higher in athen
but as magma cools its gets denser so sinks lower
35
parts of water cycle
hydrologic cycle has 4 reservoirs
- ocean
- water on land
- water vapour in atm
- solid ice
36
how water pass btw reservoirs?
```
pathways called fluxes
ocean to atm **main one** - evap
land to ocean -rivers and streams, runoff
atm to ocean -precip
atm to land - precip
land to atm -evap
```
37
which of the fluxes btw water reservoirs are important for sea water salinity determination
precip and evap are main
ocean to atm (biggest source)
atm to ocean
but also ice formation and melting changes
and runoff off from rivers decrease salinity
38
how has global water cycle been human impacted?
dams block river runoff = increase salinity = up or down of flow rate, can divert and leave stream dried up
we impact with inceased temp due to CC, increase evap
glaciers melting = CC caused
39
Principle of Constant Proportions
ratio of all major constituents responsible for salinity are is even throughout ocean INDEPENDENT OF SALINITY
well mixed
can use to determine salinity b/c can measure one and know others based on that (Cl- easiest as is biggest amount)
40
which constituents does constant proportions apply to?
```
chloride
sodium
magnesium
potassium
calcium
sulfate
^^ higher presence in ocean than others
```
41
structure of water molecule
```
2 hydrogen and one oxygen
covalent bond (strong), dipole, polar
slight imbalance gives neg charge at O and positive at H end
```
42
Water is unique. Why?
dipole causes surface tension property, as postive H end attracts to other neg Os
dipole causes universal solvent, anion and cation makes hydration shell, other polar ones, enough time can do anything
solid water less dense: from thermal properties giving strong intramolecular bonds, more spread out in lattice in solid
high heat capacity : regulate earth climate, move heat around world, hydrogen bonds broken and move freely so more heat absorbed
43
what makes ocean salty?
salinity is total amount of solid material dissolved in water (table salt, gases at low T)
ratio of dissolved to water
**fine material suspended in water is NOT salinity**
range from 0 to 37ish avg is 35% parts per thousand
salt from runoff from land, and opening in seafloor
44
important components of seawater
ya
majors are bigger in ratio and importnat
but nutrients are essential elements for like
major nuts: are N P Si, in bigger quantities
minor nuts: not less imp but less in quantity
45
less importnat components of seawater
ya
46
residence time
avg time before constituent is removed from water
only in steady states scenarios
quantify relationships btw rate of input and output
slow removal = long residence time
fast removal = short residence time
in seawater: conservative are high res, non conservative are low res
47
example of non conservative reactions with short residence time
precipitation
rock alteration
bio reactions
adsorption
48
ocean mixing
need around 1000 years of residence time to fully evenly mix and distribute around ocean (major ions and inert gases)
short residence time are not fully mixed (100 yrs for aluminium)
49
example of ion with high residence time
Na+ (260 mill years)
50
seawater density
mass of seawater in a unit volume (g/cm^3)
temperature and salinity and pressure (only at depths) can show density relationship
precip and evap most impactful: remove and add pure water to system
- evap is dependent on Temp
51
Salinity over depth
low lats: high salintiy at surface due to high T so high Evap.....down swing towards intermediate as less affected by surface things
high lats: surface is low salinity due to runoff, precip, low evap due to cold, and icebergs melting....down, swing towards middle too
52
stable water column
strong pycnocline = rapid change of T and salinity (density)
stratefied column of water =all dense at bottom, less dense at top
thermocline most impactful as T>salinity here,
upweling, downwellng cause unstability
53
Temperature - Salinity Diagram
temp vs salinity = density curves on middle
lines are constant density
used to ID deep water masses through salinity temp and therefore density
54
how to measure SST
changes with latitde
done in situ
and in space (indirect)
55
how salinity measure
used to use weight
now based on constituent principle
OR
most common is electrical conductivity
56
how are waves parameters measured
height: stationary object like pole, moored in situ devices
period: time btw troughs or crests
often times mounted on bouys and collected through satellites
out at sea have electric devices measuring parameters constantly
can be attached to a boat
NAOO (advanced)
accelerometer measures speed up or slow down
self recording pressure gauge: measures change in pressure
radar tech (parameters, change in elevation and velocity to)
57
main four deep sea sediments
lithogenous
biogenous
cosmogenous
hydrogenous
58
lithogenous sediment
- types
- how formed
2 types: neritic and pelagic
n: coarse, shelf, near islands, mostly rocks
p: fine material, deep water, volcanic eruptions, abyssal plains
derived from pre existing rock material from conts, erosion, volc dust
quartz most abundant
weathering breaking rocks, movement of small rocks
gets finer farther away it is from shore
59
neritic deposits
- cont shelves, near islands, shallow
beach deposit
cont shelf: relict sed from 3000 to 7000 yrs old
Turbidity deposits: turbidity currents carry vast amount as carve canyon, spread out in fan at head
glacial: poorly sorted, big range, ice melts and releases sed
60
biogenous sediment composed
deep ocean basins
micro orgs with tests, sink down form ooz: silica or calcium carbonate based
silica: from algea, photo, two parts shell fit together
calc: either cocco or foraminifers
- live at sruface, shell sink and create chalk once lithified
61
biogenous sediment deposition
one of most common pelagic
| three process: high productivity, dissolve at depth, dillution of other seds
62
pelagic deposits
```
abyssal clay : 70% from conts
far from land (large dist travelled)
if oxidized, red or brown then called RED clays
abundance on plains = lack of others
calcarous ooz and CCD
```
63
calcarous ooz
biogenous deposits (if more than 30% is hard shells) get this ooze
coccolithophores, foriminifers and other calcarous secreting orgs in shells (tests)
when lithifies with time makes white deposit (chalk)
64
hydrogenous sediment
from dissolved material in water (rain contributes)
small portion of overall sediment in ocean
Ex. manganese nodules, carbonates, metal sulfides, phosphates and evaporites
65
cosmogenous sediment
extraterrestrial sources
insignificant portion of ocean sediment
2 main types: micro spheruls (small globular, with nfo about past extraterrestrial) and macro meteor debris (from meteor impact site)
66
distribution of sediment in Pacific Ocean
bio in middle: calcarous ooze mainly, spots of abyssal clay (near NA and near Africa)
lith near continents at margins, at poles
67
deep water waves
| speed
floor is deeper than wave base: do not feel the bottom of the ocean (orbitals are perf circles)
wave speed is only reliant on L (wavelength)
not dependent on depth as not touching bottom
only gravity working on speed (constant)
68
transitional waves
| speed
in btw deep and shallow
| so speed depends on water depth AND wavelength
69
shallow water waves
touch the bottom so have slow down b/c of this, orbitals become squished
where depth is less than 5% of wavelength (L/20)
speed is there fore dependent on only water depth
70
wave base
L/2
neglegible movement here
Gravity too but constant
71
what is wave speed reliant on
L and T?
| depth gravity L
72
shoaling waves
```
increase in steepness
increase in increase in height
decrease in speed
decrease in wavelength
E is conserved
T stays the same
water orbitals flatten
```
73
how are tsunamis generated
from large displacement of water suddenly
tectonic plate movement moslty (fault slip, uplift or downfall of plates)
could be volcanic eruptions, landslides, underwater avalanches and slides
74
waht is a tsunami
considered shallow water wave
as bottom is touching so depth is 5% of wavelength, this is due to the enourmous wave length of 200km
so all of ocean bottom is shallow enough
acts like shallow wave as shoal (not approach like wave though)
75
where tsunamis most likley start
fault lines
plate boundarie
ring of fire
76
how to be safe in tsunami
follow directions
high ground
far away from water
77
very large wind waves
enough prosistent wind in same direction, high wind speed, and large fetch
start small but as wind continues to blow gets bigger
currents also help (three main ones around antarctic ocean) = lead to probability of rogue waves
78
rogue waves
larger than expected waves due to constructive interference
| kills
79
currents in antarctic ocean
alguhus current
benguela current
**antarctic circumpolar current
80
wave generating force
how energy is transferred to fluid =
interference btw air and water, starts oscillation
Wind in most cases (large, deep, shallow, transitional)
displacement of large volume of water (landslide,, plate uplfit downfall- tsunami)
uneven grav and centrigula attraction (tides)
81
wave disturbing force
what starts the wave
so Energy that is transfered (doesnt transfer, gen force does that
so rocks falling into water, plates uplifted or downfall
82
what restores waves
all in gravity for bigger waves
| in small capillary waves = can be surface tension
83
semi diurnal
two highs and two lows a lunar day
| heights of consecutive highs and lows similar
84
diurnal
one high and one low a lunar day
85
mixed
```
both parts
so semi diurnal usually
BUT consecutive highs and lows are unequalt
- drastic differences
most common in world
pacific NA
```
86
tidal range
vertical distance between high and low tide
87
ebb currents
outgoing tide
88
flood currents
incoming current
| up through bays and into pools
89
when are strongest ebb and flood currents
usually right before high or low tide
90
weakestcurrent in tides
slack tides
| btw ebb and flow
91
tidal bulges
from grav and centrifugal force not being balanced
side closer to moon bulges as grav > cent (Zanith)
side away from moon bulges as grav < cent (nadir)
92
neap tide
when there is destructive interference of sun and mood tide
sun at 90 degree angle to moon
lowest tide
1st and 3rd quarter
93
spring tide
highest tide
at conjuction and opposition positions of moon and sun
tides are constructive interference
2nd and 4th quarter
94
coastal upwelling
rise up of cold, nut rich water from below
good for bio, and animals
due to ekmans transport: winds blow along, push water away from coast, water has to fill from under
usually at high lats (no pycnocline = mixing allowed)
**can also have downelling if wind blow opp direction**
95
equatorial upwelling
caused by divergnece (transport R in NH and L in SH)
common on eqautor
high biodiversity
96
how does upwelling affect surface chemistry?
lower pH
more nuts
rich in nutrients and biodiversity
97
coasts where coastal upwelling occurs
along west coast of NA
| Cali and Vancouver island
98
eddys
warm and cold
as gulf stream goes on with western intensification, can curved and bend onto itself
creates closed off current of water (eddys)
30-500km d, last for months
if pulls water from Sargasso sea = warm
if pulls from coastal zones= cold
99
warm eddys
from Sargasso sea, west side of gulf
spin clockwise, drift to USA east coast
creates hill in middle as water pushed into center
warm water pushed down = eddy
drift west towards coastal waters
tranport hear from middle of gyre to coastal margins
100
cold eddys
from coastal sides of gulf stream, to the east
rotate counterclockwise
cold more abundant life and nuts
due to counter = Ekman diverges water so cold rises
moves East towards Sargasso sea
boost ships along
provide biodiverse and productive spots in unproductive sargasso sea
101
ITCZ
intertropical convergence zone
equatorial doldrums
where trade winds converge (NE and SE)
102
btw 30 N and 30 S
gyres are created in ocean
| effect of NE trade winds and prevailing westerlies
103
atm btw 30 N and 30 S
low pressure along equator
Hadley cell btw 0 and 30N and 30S
above equator air is hotter, expands, air is less dense, rises, water vapor condense and fall = dry air mass travelling away from equator
becomes denser than rest and sink
104
geostrphic currents
gyres
rotating loops in North and South Pacific Oceans
clockwise in NH and counter in SH
combined Ekman transport on trade winds and prevailing westerlies makes gyres
center (where hill is) is a bit off due to rotation of earth (R in NH)
gravity try to pull hill down, Coriolis up = equilibrium of both pulling = so flow is around gyre
105
what happens to gyres if wind drops
coriolis cannot act on non moving thing so gravity would flatten out
ocean become surface with no currents
106
gyres if no rotation of earth
would not happen as wind would mov ein straight lines across
107
gyres if earth rotated other way
everything change direction
| gyres spin in opposite ways, wind blow in opp direction
108
gryes if no continents
would be large
| contained by land masses
109
how does coriolis affect fluid motion on earth
makes moving things deflect to R in NH and L in SH
caused by earth east rotation
bigger impact on longer moving things
impact global currents, winds, gyres, impact spiral
110
ekamn spiral
water is indiv layers moving separately but wind sets entire column in motion
initial surface layer moves 45 degrees
due to drag less motion each layer
one will go all the way around
111
ekman transport
avg of movement of layers is 90 degrees of wind direction
| R in NH and L in NH
112
western boundary currents
```
part that turns due to continents on western edge of basins
comprise western boundary of gyres
intensified due to squish btw land
gulf stream is largest western current
carry water around the world
```
113
conveyor belt
start north, gets cold, sinks NAWD south to equator then to Antarctic (CPDW) - inter, those mix and become CoW - inter, AABW is below DEEPEST,
DRAW AND FINISH
114
conveyor belt on heat transport
```
moves heat around world
mediates
gulf stream is huge to mediate and such
can adsorb and redistribute heat
brings warm water around too
CC: sea level rise, ice melt,
```
115
water masses
```
NADW: north atlantic deep water
CPDW: Circumpolar deep water
CoW: common water (mix of ^^)
AABW: Antartic bottom water
AAIW: ANtarcic intermed water (sand btw AABW and NADW)
MIW: Mederterrianian intermediate water
```
116
how do we know if water mass is young or old
cna tell by amount of dissolved O in it = younger is high
- based on how long since mass left the surface, as O only impacts to O happen at surface
Use T and S as tracers, follow from the start
117
el nino sequence of events
low pressure of SA and high over Indo-Asia
similar time equatorial winds weaken or revers
sea surface high levels collapse in west
similar time warm pools move from west to east
thermocline deepens in east
WARMER
118
la nino sequence of events
SE trade winds regain strength, stronger to W now
high pressure shifts back to normal position stretches further, limiting space for low pressure to only western
strong surface winds push warm pool back west, leaving cooler SST on east
sea levels in E lower than normal so slope from E to W greater than normal (lower to up)
shallow thermocline as stretches, moves close to surface at times, slopes from w to E halfway across basin
water run to Peru upwelling
COLDER
119
ENSO effect on coastal upwelling
upwelling during el nino is warm water as it is above thermocline (thicker surface)
so not biodiverse, bad for fisheries
happens at equator too
la nina is good cold fresh waters
120
ENSO
el nino southern oscillation
| pertubation to "normal cycle" = walker cycle
121
walker cycle
normal, el and la on either side
WMWP on western boudnary due to SE trade winds = gradient of SST across basin
^^ asymmetry creates ocean atm coupling in longitudinal (walker)
122
walker conditions
W to E horizontal winds at top of lower atm
| E to W winds across ocean surface
123
biologicla pump
CO2 cycle of OM production (photosynthesis) and degredation (respiration)
photo at the top s OM decomposed below thermocline
dead bio sink and release CO2 along the way (resp)
soft parts
124
where does biological pump cycle happen
surface with light
anywhere bio is very productive
tropical, temperate areas
upwelling areas off coast
125
biologicla pump
CO2 cycle of OM production (photosynthesis) and degredation (respiration)
photo at the top s OM decomposed below thermocline
dead bio sink and release CO2 along the way (resp)
soft parts
hardparts is dissolution and precip
126
how hard parts cycled biologically
hard parts are production of calcarous shells
plankton: coccolithophores, fominifers etc
inorganic
127
where does precip dissolution cycle happen
need usnlight too
but below lysocline (dissolution CACO3 increases)
turn slihglty acidic due to more CO2 in ocean = more corrosice to CACO3 = shallow CCD
128
hard parts bio pump
precipitation of CACO3
| dissolution of CACO3
129
solubility pump
deep water thermohaline circualtion
| cycling CO2 through deep water masses
130
solubility pump
deep water thermohaline circualtion
cycling CO2 through deep water masses
physio-chemical process
transports carbon as dissolved inorganic carbon from surface down
131
jetties
protect shoreline from shoaling waves
protect boats from big waves
long perpendicular wall to shoreline
132
breakwall
removes wave E from coastal installation
effects sand deposition and removal
out in bay parrallel to shore insegments
133
groins
small wall out from the beach into the ocean
| main purpose is to keep sand on the beach
134
seawall
built for land reclamation
| protect beaches, roads, houses, communities from storm waves
135
how the four structures impact coast
all shift water from natural steady state
all increase beach eorions but if take away loss of homes etc
erosion accelerated downstream by longshore current (especially seawall where erosion amplyfied at ends)
136
BC outer water
wide shalllow shelf
then break then abyssal plains
2 currents: davidson current (S in Sum and N in WInt) and vanc island current (N)
upwelling
HG coast, narrow shelf in hecate, shallow good fishing
137
BC inner water
deeper than shelf due to recent glacial water
deepest part of georgia strait only 420m
moving from shelf to inner is big oceanography change: get unmixed water entering that stable water column is formed
138
seasonal events BC inner and outer water
outer: davidson current runs S in Summer and N in winter
139
fjord estuary
important to BC geogrpaphy, many here
fjord is classification of an estuary
from last glaciation period when sea level was 120m lower than today
after glaciers melted, take while for sea level to return, also estuarys risen due to ice melt
140
fjord
estuary formed by glaciers gauging U shaped valley as advance towards the continental shelf
glaciers retreat, leaving rock piles, debris at seaward end or valley (terminal moraine)
seawater flow over and into valley (some reminants still there sill)
driven by fresh water circulation
141
sill
barrier to deep water exchange with neighbouring water channels = making stagnent pools can lead to anoxic water
142
estuary
partially enclosed body of water with net gain or loss of fresh water
143
deep water renewal
process to renew dep water in fjords
in BC around once a year happens
if doesnt = anoxic die to decomp of OM =dead
injects dissolved O rich waters into fjord to replenish O levels
144
plume front
front btw large input of fresh waer into saline water
sharp horizontal zone
can change position depending on tides (pushing up with flood tide and back with ebb tide)
wind can blur front line through mixing
145
what marks plume front
sharp line of debris and foam on surface
| change in colour (milk green of river and dark blue of ocean)
146
what happens to water at plume front
denser ocean water sink below
| mixing at interface means fresh water becoming saltier near front
147
why are plume fronts important biologically
plankton thrive as rivers have great nut source but too cloudy, so clear nut rich plume front is great
also as mixing occurs, it is an in btw salty and fresh so good for young salmon to get accustomed to salt water
148
CCD
Calcite compensation depth
usually 4500m below surface
below this line calcite readity dissolves, not lot of depostis down there
low temp and pH, higher pressure and CO2 conc make dissolve
149
lysocline
above CCD
calcite is stable and does not dissolve
below this line calcium carbonate dissolves increasingly with increasing depth until CCD
150
how carbonate oozes found below CCD?
hvae to be covered and lithified than carried down
| so mid ocean ridge, peaks above then covers ith new molten rock and moved down below CCD
151
where rare to see CaCO3 depostis
deep ocean basins below CCD
| beneath cold high lat waters (no calcourous orgs there)
152
where does silicous ooze form
typcally below upwelling areas = where deep water rise to top
high latitudes
can be equator too due to upwelling
153
where see carbonate deposits
shallow waters with lot bio prod at the top\
warm surface water
low latitudes
mid ocean ridge
154
waters latent heat
as change from phase to phase heat has to be absorbed or released
water has high latent heat, related to high heat capacity
155
sigma-t
to measure density
p(S,T)
has no units, way to measure without all the decimals (omega little (t))
Ot = density - 1000
to use ^ density must be in Kg/cm^3
variation of sigma-tee in ocean is 22.00-28.00
156
pycnocline
rapid change in S and T (density)
oceans density profile changes with Lat
low and med : mixed layer prominant from winds
- below is pycnocline
high lats: not much change with depth (isopycnal)
** all link to stability of water column**
157
tidal wave
regular shallow wave
| bottom dragging, acts like wave with shoaling
158
trace elements
very small amounts
can help destroy or promote life
three profiles depening on residence time
- conservative (varies only with S, long time)
- nutrient (concentration varies with time and space, intermed time)
- scavenged (Short res time)
159
thermocline
rapid area of change in Temp
so at low lats where have strong therm is stable, high lats are opposite (isothermal and isopycnal)
mid lats: seasonality (summer stronger, fall lose, winter intene mixing, spring back up)
160
halocline
changing of salinity with depth
most impactful is E and P
mid lats: E>P = high Surface salinity
low lats: P>E = at covergence lots of precip
high lats: P>E = low surface salinity swing up as go down
161
amphidromic points
places where basically no tide occurs
| from each point eminatnes cotidal lines
162
co tidal lines
emanate from amphidromic points
connect all places from this point that high tide and low tide at same time
numbers on lines show hours before high tide
low is 6 hours after high tide at amphi so if "10" is high then "4" is low
rotate counter in NH (bends R) and clock in SH (Bends L)
163
corange lines
show on chart where same tidal range happens
concentric circles around amphi
range increases moving out from point
164
wave refraction
change in direction of waves as go from one medium to another (deep to shallow water)
waves approach shore on angle, end up parallel
as bottom of wave hits bottom = slows, but top faster still so bends
165
wave reflection
when collide with solid barrier
bounce back at an angle of reflection (angle wave makes with vertical)
ALWAYS = angle of incidence (angle of wave to the vertical as approaching
creates change in direction
166
orthogonal lines
90 degrees to wave crest
| to show how incoming waves refract
167
wave diffraction
when wave pass through opening or around barrier
amount of diffraction (bending) increases with increasing wavelength
**waves with L shorter than barrier, NOT DEFRACT, simply stop**
