oscar schofield ([email protected])[email protected] 932-6555 x 548, you are better off...
TRANSCRIPT
Oscar Schofield ([email protected])932-6555 x 548, you are better off just walking in if you need help, if I can’t I will let you know, but it is quicker then trying to make a formal appointment, ask Judy I am a schedule-organization disaster……
Light and PhotosynthesisLight and Photosynthesis
1) Light in the OceanI) IntensityII) ColorIII) Inherent Optical PropertiesIV) Apparent Optical PropertiesV) Remote Sensing
2) PhotosynthesisI) Light AbsorptionII) Light ReactionsIII) Dark Reactions
For satellite remote sensing the wavelength is the key to what
you want to measure.
c = = hhc
Figure 6
I) Light
Z (meters)
Irradiance Intensity
Lambert Beers LawEd2 = Ed1e-z*Kd
Ed2
Ed1z1
z2
z
1) Because of Lambert Beers Lawthe ocean is dim
2) Plant life is dependent on light
3) The 1% light levelfor the majority of the is 100 m or less?
2500 2500 mol photons mmol photons m-2-2 s s-1-1
5.0 5.0 mol photons mmol photons m-2-2 s s-1-1
Alexander the Great
Early Optics
The color of the sea shows a great deal of variability from the deep violet-blue of the open ocean to degrees of green and brown in coastal regions. Before the advent of sensitive optical instruments, color was determined by visual comparison against standard reference standards such as the Forel Ule Color scale.
Your future will include robots patrolling the watersfor you as optical instruments are now small
74:10 74:00 73:50 73:40 73:30 73:20 73:10
16-Sep-2004 15:00:53 - 23-Sep-2004 11:57:27
Temperature
bb(532)/c(532)
bb532
10
30
50
70
90
110
10
30
50
70
90
110
10
30
50
70
90
110
Now we can study during storms
Depth-Averaged CurrentsSurface Currents
Tropical Storm Ivan
What kind of measurements are there?What kind of measurements are there?
Inherent Optical PropertiesInherent Optical Properties: Those optical properties that are : Those optical properties that are fundamental to the piece of water, not dependent on the geometric fundamental to the piece of water, not dependent on the geometric structure of the light field. (absorption, scattering, attenuation) structure of the light field. (absorption, scattering, attenuation)
Apparent Optical PropertiesApparent Optical Properties: Those optical properties that are : Those optical properties that are fundamental to the piece of water and are dependent on the geometric fundamental to the piece of water and are dependent on the geometric structure of the light field. (light intensity, reflectance) structure of the light field. (light intensity, reflectance)
Why IOP Measurements?
• Absorption, a color• Scattering, b clarity• Beam attenuation, c (transmission)
a + b = c
The IOPs tell us something about the particulate anddissolved substances in the aquatic medium; how we measure them determines what we can resolve
Why IOP Measurements?Why IOP Measurements?
• Absorption, a colorAbsorption, a color
Photo S. EtheridgePhoto S. Etheridge
Why IOP Measurements?• Absorption, a• Scattering, b
clarity
Review of IOP Theory
o
IncidentRadiant Flux
No attenuation
TransmittedRadiant Flux
t
Review of IOP Theory
Attenuation
to
IncidentRadiant Flux
TransmittedRadiant Flux
Loss due to absorption
a Absorbed Radiant Flux
o
IncidentRadiant Flux
t
TransmittedRadiant Flux
Loss due to scattering
b Scattered Radiant Flux
o
IncidentRadiant Flux
t
TransmittedRadiant Flux
Loss due to beam attenuation
(absorption + scattering)
a Absorbed Radiant Flux
b Scattered Radiant Flux
to
IncidentRadiant Flux
TransmittedRadiant Flux
Conservation of radiant flux
a Absorbed Radiant Flux
b Scattered Radiant Flux
o = t + a + b
to
IncidentRadiant Flux
TransmittedRadiant Flux
Beam Attenuation Measurement Theory
t
a
b
c = fractional attenuance per unit distance, attenuation coefficient
c = C/x
c x = -/
c x = -ln(t/o)
c (m-1) = (-1/x)ln(t/o)
o
x
0 c dx = -0 d/x x
c(x-0) = -[ ln(x)-ln(0)]
c x = -[ ln(t)-ln(o)]
1m 1m
Underwater Eye ChartUnderwater Eye Chart
11:4011:40
TIMETIME
Optical MooringOptical Mooring
c532c532
13:4013:4015:4015:4018:2018:20
19:2519:25
Phytoplankton
CDOM-Rich Water
SuspendedSediments
Benthic Plants1/Kd1/Kd
Optically-ShallowOptically-ShallowOptically-DeepOptically-Deep
Micro-bubbles
Whitecaps
Shallow Ocean Floor
1) Collect a signal, about 95% of the signal is determined by the atmosphere.
2) Relate the reflectance to the physics, chemistry, and/or biology in the water.
R = Bb/(a+Bb)
-0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
400 450 500 550 600 650 700
wavelength (nm)
Ab
sorp
tion
(1/
m)
Phytoplankton Dissolved organics
Changing the relative Changing the relative proportions of materialsproportions of materials
in the water column also impacts in the water column also impacts color of the watercolor of the water
Distance (km)
0 1Absorption (m-1)
0 0.03Backscatter (m-1)
Dep
th (
m)
0
12
6
0 2 4 6 8 10
Dep
th (
m)
0
12
6
Distance (km)0 2 4 6 8 10
Distance (km)0 2 4 6 8 10
Distance (km)0 2 4 6 8 10
Dep
th (
m)
0
12
6
Dep
th (
m)
0
12
6
Bb488 Bb589
a490 a550
a490/a5500.5
1
1.5
2
0 5 10
Bb488/Bb589
Distance (km)
Rat
io
That Pristine Blue NJ WaterThat Pristine Blue NJ Water
Courtesy of Hans Graber, Rich Garvine, Bob Chant, Andreas Munchow, Scott Glenn and Mike Crowley
Target 3 mTarget 3 mBased on Surface Based on Surface
Values Values
Influence of OpticalInfluence of OpticalProperties on Properties on
Laser Performance Laser Performance
Changes in the color of the reflectance as theChanges in the color of the reflectance as theload of material changes in the water column.load of material changes in the water column.
Water Leaving RadianceWater Leaving Radiance ReflectanceReflectance
Color variability at multiple scales
around Tasmaniafrom CZCS image
Causes?Strong winds,
strong currents,bottom togography,
etc.
GSFC, NASA
Tasmania
a z c z aph ii
n
i' ( , ) ( ) ( ) = ⋅=
∗∑1
a z c z aph ii
n
i' ( , ) ( ) ( ) = ⋅=
∗∑1
0
0.1
0.2
0.3
400 500 600 700
wavelength (nm)wavelength (nm)
ph
ytop
lan
kto
n a
bso
rpti
on (
m-1)
0.0
0.02
0.04
0.06
0.08
400 450 500 550 600 650 700
chl a
chl b
chl c
PSC
PPC
wavelength (nm)
abso
rpti
on c
oeff
icie
nt
(m2 m
g-1)
0
5
10
15
20
400 450 500 550 600 650 700
Wavelength (nm)
Spectral Irradiance (
W cm
-2 nm-1)
chl a chl achl b
chl cchl b
carotenoids
phycobilins
0
0.25
0.50
0.75
1.0
1.25
Rel
ativ
e A
bsor
ptio
n
chl a-chl c-carotenoidschl a-chl b-carotenoidschl a-phycobilins
Chlorophyll a : all phytoplankton (used as a measure of concentrations)
Chlorophyll b : green algae
Chlorophyll c : chromophytes (dinoflagellates, diatoms, coccolithophorrids)
Carotenoids : fucoxanthin (dinoflagellates, diatoms, coccolithophorrids)19’-hexanoyfucoxanthin (coccolithophorrids)alloxanthin (cryptophytes)peridinin (dinoflagellates)
Ene
rgy
hv
GroundState
DifferentExcitation
OrbitalsIn a molecule
Heat Fluorescence
Photosynthesis
Energy gained
PAR
Light-Harvesting PigmentsLight-Harvesting Pigments
RC II RC I
e -
Q
A
QB 2H+
PQH2
2H+
FdCO
2CH2O
P680+
z
2H2O O2 + 4H+
FluorescenceFluorescence
THYLAKOID THYLAKOID MEMBRANEMEMBRANE
STROMASTROMA
CYTOSOLCYTOSOL
LHCLHC LHCLHC
1/2 O2 + 2H+H2O
4Mn Yze-
2H+
PQ
PQPQ
PQPQ
Qb
Qb
Cyt
och
rom
e b 6-
f-F
e nn
2H+
2H+2H+
PC/cyt c6
Ph
otos
yste
m I
CHLOROPLASTCHLOROPLAST
P700
A0
Fx
Fa/ Fb
Fd
AT
P s
ynth
ase
com
plex
CF0
CF1
3/2ADP + 3/2Pi 3/2ATP + 3/2Pi
NADPHH+ + NADP+6H+
1/2CH2O + 3/2ADP + 3/2PiH+ + 1/2CO2
THYLAKOID LUMENTHYLAKOID LUMEN
EP680
Pheo
e-
e-
Ph
otos
yste
m I
ID2D1
E
Qa
Qb
2 x e-
PH
Min
ute
s to
Hou
rs
NUCLEUSNUCLEUS
PLHC geneLHC gene
Repressor proteins
Day
s to
Wee
ks
fluorescence
light intensitylight intensity
oxyg
en
evolu
tion
oxyg
en
evolu
tion
0
0.5
1.5
2.5
3.5
0 50 100 150 200 250 3000
0.02
0.04
0.06
0.08
qu
an
tum
yie
ld o
f oxyg
en
evolu
tion
qu
an
tum
yie
ld o
f oxyg
en
evolu
tion
Pmax
Irradiance Intensity
Z (meters)
Ik
Photosynthesis
BiomassNutrients