Photosynthetically Available Radiation (PAR)
PI Makio C. Honda
1. Objective
The objective of this measurement is
investigate the air and underwater light conditions
respective stations and to determine depths for in situ
simulated in situ measurement of primary production
using carbon stable isotope (C-13) during late autumn.
addition, optical data can be used for the validation
satellite data.
to
at
or
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2. Description of instruments deployed
The instrument consisted of the SeaWiFS Profiling
Multichannel
Radiometer
(SPMR)
and
SeaWiFS
Multichannel Surface Reference (SMSR). The SPMR was
deployed in a free fall mode through the water column (see
right picture). The SPMR profiler called “Free Fall” has a 13
channel irradiance sensors (Ed), a 13 channel radiance sensors
(Lu), tilt sensor, and fluorometer. The SMSR has a 13
channel irradiance sensors (Es) and tilt meter (Table 1).
These instruments observed the vertical profiles of visible and
ultra violet light and chlorophyll concentration.
Table 1. Center wavelength (nm) of the SPMR/SMSR
Es 379.5 399.6 412.2 442.8 456.1 490.9 519.0 554.3 564.5 619.5 665.6 683.0 705.9
Ed 380.0 399.7 412.4 442.9 455.2 489.4 519.8 554.9 565.1 619.3 665.5 682.8 705.2
Lu 380.3 399.8 412.4 442.8 455.8 489.6 519.3 554.5 564.6 619.2 665.6 682.6 704.5
Optical measurements by Free Fall were conducted at our time-series station K2 and
S1. Measurements should be ideally conducted at median time. However observations were
conducted irregularly because of limited ship-time and other observation’s convenience (Table 2).
The profiler was dropped twice a each deployment to a depth of 200 m. The SMSR was
mounted on the anti-rolling system’s deck and was never shadowed by any ship structure. The
profiler descended at an average rate of 1.0 m/s with tilts of less than 3 degrees except near surface.
Observed data was analyzed by using software “Satlantic PPROSOFT 6” and extinction rate and
photosynthetically available radiation (PAR) were computed.
3. Data file
Data is vertical profile of PAR calculated each 1 dbar upper 150 ~ 200 dbar. Data file
consists of the following information.
4. Summary of data set
Vertical profiles of PAR were several times observed at each station during each cruise. The
followings are summary of locations of PAR observation and principal characteristics for
respective cruises.
(1) MR10-01
Date and
Time
(UTC)
2010.1.23
23:55
2010.1.25
4:12
2010.1.31
4:09
2010.2.1
2:57
Euphotic layer*
(m)
Memo
47N/160E
Leg.1
8.8 x 1015
~ 79
1 day before PP incubation
K2-2
47N/160E
4.3 x 1015
~ 86
during PP incubation #1
S1-1
30N/145E
7.1 x 1016
~ 81
1 day before PP incubation
S1-2
30N/145E
6.7 x 1016
~ 86
during PP incubation #1
Leg.2
9.5 x 1016
~ 82
1 day before PP incubation
~ 105
during PP incubation #1
~ 69
1 day before PP incubation
Station
Lat./Long
.
Surface PAR
(quanta cm-2 sec-1)
K2-1
2010.2.9
S1-1
30N/145E
3:11
2010.2.10
S1-2
30N/145E
3.6 x 1016
2:43
2010.2.15
K2-1
47N/160E
5.7 x 1016
0:50
* Euphotic layer: 0.5% of surface PAR
(2) MR10-06
(Date and Time in LST: UTC+11hr at station K2 and UTC+10hr at station S1)
Date and
Station Lat./Long
Surface PAR
Time (LST)
.
(quanta cm-2 sec-1)
2010.10.25
K2
47N/160E
8.7 x 1015
12:02
2010.10.28
K2
47N/160E
5.2 x 1016
11:22
2010.10.29
K2
47N/160E
9.5 x 1015
14:55
2010.11.07
S1
30N/145E
1.2 x 1016
11:27
2010.11.08
S1
30N/145E
1.5 x 1016
10:00
2010.11.09
S1
30N/145E
6.4 x 1016
14:41
2010.11.10
S1
30N/145E
5.3 x 1016
11:27
* Euphotic layer: 0.5% of surface PAR
Euphotic layer*
(m)
~ 56
~ 45
~ 56
~ 100
~ 101
~ 103
~ 102
Memo
1 day before PP incubation
#1
during PP incubation #1
1 day before PP incubation
#2
1 day before PP incubation
#1
during PP incubation #1
1 day before PP incubation
#2
during PP incubation #2
(3) MR11-02
(Date and Time in LST: UTC+10hr at station K2 and S1)
Date and
Time
2011.2.14
Lat./Long
.
30N/145E
Surface PAR
(quanta cm-2 sec-1)
8.7 x 1016
Euphotic layer*
(m)
74m
S1
30N/145E
7.8 x 1016
74m
during S1-PP incubation #1
S1
30N/145E
5.3 x 1016
84m
K2BF
44-23N /
156-15E
3.8 x 1016
75m
1 day before S1-PP
incubation #2
1 day before K2-PP
incubation #1
11:25 (LST)
2011.2.15
Memo
Statio
n
S1
1 day before S1-PP
incubation #1
11:22
2011.2.17
12:30
2011.2.25
11:34
* Euphotic layer: 0.5% of surface PAR
(4) MR11-05
(Date and Time in LST: UTC+11hr at station K2, UTC+10hr at station S1 and UTC+9hr at
station F1)
Date and
Station Lat./Long.
Surface PAR
Euphotic layer*
Memo
Time (LST)
(quanta cm-2
(m)
sec-1)
2011.06.30
K2
47N/160E
4.7 x 1016
~ 46
1 day before PP incubation
10:50
#1
2011.07.01
K2
47N/160E
3.0 x 1016
~ 42
during PP incubation #1
11:18
2011.07.04
K2
47N/160E
2.8 x 1016
~ 47
1 day before PP incubation
11:03
#2
16
2011.07.05
K2
47N/160E
7.4 x 10
~ 46
during PP incubation #2
11:03
2011.07.7
K2
47N/160E
5.0 x 1016
~ 45
1 day before PP incubation
11:03
#3
16
2011.07.8
K2
47N/160E
9.3 x 10
~ 45
during PP incubation #3
11:03
2011.07.12 Before 36-40 N /
5.3 x 1016
~ 45
1 day before PP incubation
11:03
F1
142-01E
at station F1
2011.07.13
F1
36-29N /
1.2 x 1017
~ 67
during PP incubation #1
11:06
141-30E
2011.07.24
S1
30N/145E
1.2 x 1017
~ 107
1 day before PP incubation
13:06
#1
2011.07.24
S1
30N/145E
1.2 x 1017
~ 104
during PP incubation #1
13:06
2011.07.27
S1
30N/145E
1.1 x 1017
~ 96
1 day before PP incubation
11:01
#2
16
2011.07.28
S1
30N/145E
8.8 x 10
~ 95
during PP incubation #2
10:36
* Euphotic layer: 0.5% of surface PAR
(5) MR12-02
(Date and Time in LST: UTC+11hr at station K2, UTC+9hr at station S1)
Date and
Time (LST)
Station
Lat./Long.
Surface PAR
(quanta cm-2
sec-1)
6.5 x 1016
2012.06.10
K2
47N/160E
11:57
2012.06.111
K2
47N/160E
4.4 x 1016
1:47
2012.06.13
K2
47N/160E
6.8 x 1016
10:32
2012.06.14
K2
47N/160E
4.6 x 1016
11:30
2012.06.27
S1
30N/145E
3.2 x 1016
11:40
2012.06.28
S1
30N/145E
5.8 x 1016
11:34
2012.06.30
S1
30N/145E
1.3 x 1017
09:55
2012.７.1
S1
30N/145E
4.4 x 1016
11:40
* Euphotic layer: 0.5% of surface PAR
Euphotic layer*
(m)
Memo
~ 50
1 day before PP incubation
#1
during PP incubation #1
~ 46
~ 55
~ 54
~ 82
~ 82
~ 91
~ 92
1 day before PP incubation
#2
during PP incubation #2
1 day before PP incubation
#1
during PP incubation #1
1 day before PP incubation
#2
during PP incubation #2