Sensor Functionality Summary
CMO Deployment 1: 07/08/96 - 09/26/96 (Year Day 190 to 270)
Table 1: 13.5 m Sensors
Sensor |
Estimate of Failure Date |
Comments |
PAR SN 4200 |
JD 248 |
Bio-fouling |
Temperature SN 1839 |
NONE |
N/A |
Lu 683 SN 7029 |
NONE |
N/A |
WETStar Fluorometer SN 038 |
NONE |
N/A |
Transmissometer SN 408 |
JD 220 |
Heavy biofouling |
ac-9 SN 114 |
JD 242 |
Bromine solution contamination |
Table 2: 37 m Sensors
Sensor |
Estimate of Failure Date |
Comments |
PAR SN 4216 |
NONE |
N/A |
Temperature SN 1667 |
NONE |
N/A |
Lu 683 SN 7021 |
NONE |
N/A |
WETStar Fluorometer SN 039 |
NONE |
N/A |
Transmissometer SN 410 |
JD 240 |
Heavy biofouling |
ac-9 SN 158 |
JD 251 |
Biofouling |
Table 3: 52 m Sensors
Sensor |
Estimate of Failure Date |
Comments |
PAR SN 4213 |
NONE |
N/A |
Temperature SN 1840 |
NONE |
N/A |
Sea Tech Fluorometer SN 144 |
JD 252 |
Slightly biofouled |
WETStar Fluorometer SN 040 |
NONE |
N/A |
Transmissometer SN 525 |
JD 268 |
Biofouling |
ac-9 SN 161 |
NONE |
N/A |
Table 1: 68 m Sensors
Sensor |
Estimate of Failure Date |
Comments |
Temperature SN 1841 |
NONE |
N/A |
Sea Tech Fluorometer SN 302 |
NONE |
N/A |
WETStar Fluorometer SN 009 |
NONE |
N/A |
Transmissometer SN 409 |
NONE |
N/A |
ac-9 SN 159 |
NONE |
N/A |
Fig. 3: 13.5m Sensor functionality timeline, Fig. 4: 37m Sensor functionality timeline
Fig. 5: 52m Sensor functionality timeline, Fig. 6: 68m Sensor functionality timeline
Calibration Record and Sensor List
CMO Deployment 1: 07/08/96 - 09/26/96 (Year Day 190 to 270)
The Biospherical Instruments, Inc. PAR sensors (QSP-200) and 683 sensors (MRP-200) were factory calibrated using a
National Institute of Standards and Technology (NIST) traceable 1000 watt type FEL Standard of Spectral Irradiance
(QSP-200 User's Manual, 1995; MRP User's Manual, 1995) (see program flowchart for specific equations used).
Calibrations for the Sea-Bird Electronics, Inc. SBE 3 temperature sensor were performed by the Northwest Regional
Calibration Center (NRCC), operating under contract to NOAA. The NRCC uses an equation (see program flowchart) derived
from Bennett's formula (Sea Bird SBE 3 User's Manual, 1995).
A combination of factory and user calibrations was used for the Sea Tech, Inc. transmissometers. Air calibration
values for the instruments were taken from the Sea Tech Transmissometer Manual, 1993, as well as a zero offset value.
Because air calibration may change with time due to a decrease in LED light output, a measurement of current air
calibration values is necessary to account for the change. The highest voltage recorded in the data file prior to the
instrument entering the water and after cleaning of the optical windows with ethyl alcohol is used for the present air
calibration. For specific calibration equations, see program flowchart.
To convert DC volts measured by the WETStar and Sea Tech fluorometers, calibrations using in situ seawater can be
performed to measure chlorophyll concentrations. Unfortunately, in situ calibrations of the fluorometers were not
available. Factory calibrations were used for the WETStar fluorometers, and calibrations performed by Norm Nelson at the
Bermuda Biological Station for Research (BBSR) were used for the Sea Tech fluorometers. To calibrate the instruments,
voltage outputs for a blank solution (pure seawater) and solutions containing varying concentrations of chlorophyll were
measured. A linear fit can be applied to the plot of [Chl]solution versus Voltsmeasured (Vmeas) because the fluorometers'
responses are approximately linear over their measurement ranges. The following equation is used for calibration:
[Chl]in situ = b + m * Vmeas, where m is the slope of the linear fit, and b is the y-intercept. The factory calibrations
for the WETStar fluorometers utilized only a pure water solution and a 1.0 mg/l solution of coproporphyrin tetramethyl
ester, where 1.0 mg/l of copro. is approximately equal to 50 ug/l of chlorophyll in a Thallassiosira weissflogii
phytoplankton culture (WETStar Fluorometer User's Guide Version 1.0, 1995). Varying concentrations of Thallassiosira
weissflogii phytoplankton culture were used in the calibration solutions utilized by Norm Nelson (BBSR) for the Sea Tech
fluorometers (Nelson, personal communications).
WET Labs calibrates the ac-9 to provide a reading of 0.00 for each channel in specially filtered clean, fresh water.
An offset value was determined during the calibration process which, when added to the raw instrument output in clean
water, provides zeroes for all wavelengths at a specific temperature. Therefore, the final output of the ac-9 is the
absorption and attenuation coefficients with pure water values subtracted out. In addition to calibrations, corrections
for internal temperature, scattering, and salinity and in situ temperature (a715 only) need to be applied. These
corrections are described in the ac-9 program flowchart.
Complementary calibrations were also performed for the temperature, transmissometer beam c (660), fluorometer
fluorescence, and the absorption and beam attenuation coefficients measured by the WET Labs ac-9. The data obtained
from the BIOPS sensors were compared to profile and discrete bottle sample data taken from ships near the CMO mooring
site on August 26, 1996 (pre-hurricane Edouard), and September 4, 1996 (post-hurricane Edouard). The data obtained from
the BIOPS Sea-Bird Inc. temperature sensors were compared to temperature profiles taken by H. Sosik of WHOI, R. Zaneveld
of OSU, and W. Gardner of Texas A&M. Transmissometer profiles taken by W. Gardner were compared with the beam c (660)
values measured by the BIOPS Sea Tech Inc. transmissometers. Fluorescence measured by the BIOPS WETStar fluorometers
was vicariously calibrated with chlorophyll concentrations calculated from discrete water samples taken by H. Sosik of
WHOI. Absorption spectra plotted from the discrete water samples were compared with the absorption coefficients measured
from the ac-9. The ac-9 data were also calibrated with profile ac-9 values measured by R. Zaneveld of OSU.
Calibration constants for all instruments are listed in Tables 5-8.
Table 5: 13.5 m BIOPS
Equipment |
Serial Number |
Calibration Constant |
Date Calibrated |
PAR |
4200 |
-7.41E-18 (V/(quanta/cm^2/sec)) gain in data file |
06/13/96 |
Temperature |
1839 |
g=4.78968540E-03 h=6.80028033E-04 i=3.41654389E-05 j=3.28348348E-06 f0=1000.00 |
07/06/95 |
Lu 683 |
7029 |
0.387 ((uW/cm^2/nm/sr)/V) gain in data file |
01/10/95 |
WETStar Fluor |
038 |
[Chl]=-1.5525+15.371 Volts |
07/31/95 |
Transmissometer |
408 |
air cal=4.657 ship cal in data file zero cal=0.001 |
12/15/94 |
ac-9 |
114 |
Channel N Kt T0
a650 7.644407 -0.000191 25
a676 7.639203 -0.000115 25
a715 7.157553 -0.000060 25
c510 8.023093 -0.000511 25
c532 8.057921 -0.000440 25
c555 8.115287 -0.000327 25
a412 7.231372 0.002209 25
a440 7.272642 -0.000868 25
a488 7.418883 -0.000397 25
c650 7.925630 -0.000250 25
c676 7.827816 -0.000051 25
c715 7.326038 0.000105 25
a510 7.471419 -0.000287 25
a532 7.530348 -0.000363 25
a555 7.609726 -0.000142 25
c412 7.386288 -0.002197 25
c440 7.605761 -0.001407 25
c488 7.950158 -0.000822 25
|
04/26/96 |
Table 6: 37 m BIOPS
Equipment |
Serial Number |
Calibration Constant |
Date Calibrated |
PAR |
4216 |
-8.91E+16 (V/(quanta/cm^2/sec)) gain in data file |
07/27/94 |
Temperature |
1667 |
g=3.68103587E-03 h=5.88939075E-04 i=1.46481589E-05 j=2.59140710E-06 f0=1000.00 |
05/13/94 |
Lu 683 |
7021 |
0.425 ((uW/cm^2/nm/sr)/V) gain in data file |
03/18/96 |
WETStar Fluor |
039 |
[Chl]=-1.4804+16.634 Volts |
07/31/95 |
Transmissometer |
410 |
air cal=4.653 ship cal in data file zero cal=0.00 |
05/08/96 |
ac-9 |
158 |
Channel N Kt T0
a650 8.635027 0.000556 25
a676 8.628047 0.000404 25
a715 8.070818 0.000560 25
c510 7.227980 -0.001473 25
c532 7.317857 -0.001107 25
c555 7.205041 -0.001205 25
a412 7.999630 -0.000557 25
a440 8.121775 0.000250 25
a488 8.334796 0.000677 25
c650 7.192533 -0.001028 25
c676 7.160159 -0.000879 25
c715 6.633011 -0.000795 25
a510 8.427886 0.000655 25
a532 8.504167 0.000607 25
a555 8.595193 0.000566 25
c412 6.402489 -0.001385 25
c440 6.762266 -0.001679 25
c488 7.145354 -0.001043 25
|
06/28/96 |
Table 7: 52 m BIOPS
Equipment |
Serial Number |
Calibration Constant |
Date Calibrated |
PAR |
4213 |
-9.15E+16 (V/(quanta/cm^2/sec)) gain in data file |
03/30/94 |
Temperature |
1840 |
g=4.80751404E-03 h=6.72529483E-04 i=3.09425422E-05 j=2.94379664E-06 f0=1000.00 |
07/06/95 |
Sea Tech Fluor |
144 |
[Chl]=-0.40+0.441 Volts |
06/93 |
WETStar Fluor |
040 |
[Chl]=-1.3536+16.92 Volts |
07/31/95 |
Transmissometer |
525 |
air cal=4.682 ship cal in data file zero cal=0.00 |
04/27/92 |
ac-9 |
161 |
Channel N Kt T0
a650 6.086019 0.000155 25
a676 6.163169 0.000073 25
a715 5.712537 0.000058 25
c510 7.265228 -0.000900 25
c532 7.360747 -0.000910 25
c555 7.473863 -0.000580 25
a412 4.768791 -0.002570 25
a440 5.036628 0.000423 25
a488 5.335945 0.000416 25
c650 7.262988 -0.000530 25
c676 7.139360 -0.000500 25
c715 6.668568 -0.000055 25
a510 5.476077 0.000315 25
a532 5.605134 0.000207 25
a555 5.745913 0.000264 25
c412 6.579548 -0.001400 25
c440 6.904813 -0.001210 25
c488 7.268749 -0.001050 25
|
06/29/96 |
Table 8: 68 m BIOPS
Equipment |
Serial Number |
Calibration Constant |
Date Calibrated |
Temperature |
1841 |
g=4.77280432E-03 h=6.64892731E-04 i=2.83626842E-05 j=2.55381921E-06 f0=1000.00 |
07/06/95 |
Sea Tech Fluor |
302 |
[Chl]=-0.40+0.441 Volts |
06/93 |
WETStar Fluor |
009 |
[Chl]=-0.8927+7.7593 Volts |
02/28/95 |
Transmissometer |
409 |
air cal=4.793 ship cal in data file zero cal=0.00 |
10/05/90 |
ac-9 |
159 |
Channel N Kt T0
a650 5.948741 -0.000190 25
a676 6.049155 -0.000400 25
a715 5.657518 -0.000490 25
c510 7.468002 -0.000690 25
c532 7.502076 -0.000510 25
c555 7.427692 -0.000760 25
a412 4.576480 -0.003030 25
a440 4.876258 0.000006 25
a488 5.174808 0.000115 25
c650 7.322390 -0.000600 25
c676 7.249863 -0.000620 25
c715 6.645701 -0.000590 25
a510 5.313438 -0.000016 25
a532 5.426282 -0.000210 25
a555 5.585068 -0.000110 25
c412 6.980224 -0.001900 25
c440 7.165783 -0.001390 25
c488 7.448023 -0.000810 25
|
07/18/96 |
Guide to Data Processing
CMO Deployment 1: 07/08/96 - 09/26/96 (Year Day 190 to 270)
ac-9 Data
INPUT: Raw binary data
13.5 m: cac1xxx
37 m: cbc1xxx
52 m: ccc1xxx
68 m: cdc1xxx
FORTRAN 77 Files: oldcmo10.f (13.5m)
oldcmo30.f (37m)
oldcmo50.f (52m)
oldcmo70.f (68m)
Programs convert data to scientific values with physical units.
OUTPUT: ASCII matrix (21 by n)
13.5 m: acac1xxx
37 m: acbc1xxx
52 m: accc1xxx
68 m: acdc1xxx
Time-series and spectra plots were created with Matlab.
One-hour averaging was accomplished by running matlab file ac9smooth.m.
Temperature, salinity, and scattering corrections can be made in Matlab.
All Other BIOPS Data
INPUT: Raw hex data
13.5 m: cac1xxx
37 m: cbc1xxx
52 m: ccc1xxx
68 m: cdc1xxx
FORTRAN 90 Files: cmo683M10.f (13.5m)
cmo683M30.f (37m)
cmopar50.f (52m)
cmopar70.f (68m)
Converts data from hex characters to volts, then from volts to
physical units, applying calibration constants where necessary.
OUTPUT: ASCII Matrix (6 by n)
13.5 m: pac1xxx
37 m: pbc1xxx
52 m: pcc1xxx
68 m: pdc1xxx
Plots were made with graphing program Matlab.
Smoothing was acheived by using matlab program runave.m.
Program Flowcharts
MO Deployment 1: 07/08/96 - 09/26/96 (Year Day 190 to 270)
For PAR, temp, 683, fluorometers, transmissometer; written in Fortran
START
1) Define variables
2) Sequential file routine; LOOP around 'x' number of files
3) Open input file
4) Open output file
5) List calibration constants: PAR multiplier, temperature constants,
transmissometer cal numbers
6) Outer LOOP (until end of file)
7) Find 'BBBB' line, call subroutine 'bbbb' to calculate Julian day
8) Find 'EEEE' line
9) Read in a blank line, if first four characters are '$E$E', goto
end of program (close input file)
10) LOOP for 8 sets of data
11) Read in PAR line, calculate volts, PAR
12) Read temperature line, calculate volts, temperature
13) Read in Sea Tech fluorometer line, calculate volts,
fluorescence (or 683)
14) Read in WETStar fluorometer, calculate volts,
fluorescence
15) Read in transmissometer line, calculate volts, Beam c
16) Write out Julian Day, PAR, temperature, fluorescence
(or 683), WETStar fluorescence, and beam c to output
17) END LOOP
18) END LOOP
19) END LOOP (SEQUENTIAL FILE)
SUBROUTINES AND FUNCTIONS:
Subroutine bbbb(junk, dattim)
Reads line to determine month, day, hr, min, and sec, converts them
into Julian day by calling function 'julian'.
Function julian:
Changes characters for month, day, hour, minute, and second into
ASCII characters, calculates a Julian day.
Function hexdec:
Changes hex characters to appropriate decimal value.
APPROPRIATE EQUATIONS:
Equation to calculate PAR (uE/m^2/s):
(pcount * 5 / 4095) * pcal = par in volts (pvolt)
gain value 1, 2, or 3 ; gain = -10 ^ 1, 2, or 3
par = ((pvolt / gain) / 6.022E+17 (conv.)) * 10000 (conv.)
Equation to calculate temperature (oC):
Use calibration constants and the following equation:
1 / {g + h [ln(f0/f)] + i [ln2(f0/f)] + j [ln3(f0/f)]} - 273.15
Equation to calculate fluorescence from Sea Tech (ug/l):
Get fluorescence in volts: (fcount * 5 / 4095) = fvolt
Use cal. eq. to get fluorescence in ug/l: offset(b) + gain(m) * fvolt
Equation to calculate 683 (uW/m^2/nm/sr):
(scount * 5 / 4095) * scal = 683 in volts (svolt)
683 = (svolt / sgain) * 10000 (conv.)
Equation to calculate fluorescence from WETStar (ug/l):
Get fluorescence in volts: (wcount * 5 / 4095) = wvolt
Use cal. eq. to get fluorescence in ug/l: offset(b) + gain(m) * wvolt
Equation to calculate Beam c from transmissometer (1/m):
Beam c in volts (trvolt) = (trcount * 5 / 4095)
Use the following two equations:
1) 20 * (factory air cal / self air cal) * (trvolt - zero off) = step1
2) [ln(step1 / 100)] / 0.25 = beam c
For the ac-9; written in Fortran
START
1) Define variables and arrays
2) Sequential file routine; LOOP around 'x' number of files
3) Open input file
4) Open output file
5) Enter calibration constants N, Kt, and T0
6) Call subroutine 'readfile' to read the entire file, byte by byte
7) Set lp (index variable for cursor) to ONE
8) Read blank line at top of file by calling subroutine 'readline',
update lp
9) Read '%B%B' line by calling subroutine 'readline', update lp
10) Read 'MT DY…' line by calling subroutine 'readline', update lp
11) Read blank line by calling subroutine 'readline', update lp
12) IF first three bytes are 'PAR', read until no lines begin with
'PAR', update lp
13) ELSE IF four bytes are 'BBBB', read 'BBBB' line
14) Calculate Julian Day with function julian, update lp
15) LOOP
16) Read from lp to lp+642 in groups of four characters
17) IF four sequential characters are '00FF00FF', update lp,
continue
END LOOP
18) ELSE IF first four bytes are the characters for '00FF00FF'
19) LOOP
20) Read from lp to lp+642 in groups of four characters
21) IF four sequential characters are 'EEEE', update lp,
goto (12)
END LOOP
22) Read 18 bytes of '00FF00FF' header line, update lp
23) LOOP 10 times
24) Read 56 characters: 2 bytes of time, and 54 bytes of
signal channel (18 groups of 3 characters), update lp
25) Convert signal channel characters into decimal
26) Calculate csig and asig
27) Calculate time, and add to Julian Day
END LOOP
28) Read 56 characters: 54 bytes of reference channel (18
groups of 3 characters), two bytes of temperature, update lp
29) Convert reference channel characters into decimal
30) Calculate cref and aref
31) Calculate temperature in counts
32) Call function 'temp' to get temperature in degrees Celsius
33) LOOP 10 times
34) Convert csigs and asigs into scientific data (c and a)
using appropriate equation and calibration constants
35) Calibrate c and a channels for internal temperature using
appropriate equation
36) Write Julian Day, a, and c, temp to output file
END LOOP
37) Read eight bytes (checksum and extra bytes), update lp
38) ELSE call subroutine 'readline', update lp
39) END IF
40) Close input file
41) Close output file
END LOOP (SEQUENTIAL FILE)
SUBROUTINES AND FUNCTIONS
Subroutine readfile:
Reads the entire character file byte by byte and returns the total
number of bytes in the file
Subroutine readline:
IF first 3 characters of a line are 'PAR', length is 45 characters
ELSE IF first 4 characters are 'BBBB', length is 112 characters
ELSE IF first 4 characters are '00FF00FF', length is 642 characters
ELSE IF first 4 characters are 'EEEE', the length is 20 characters
ELSE read one byte at a time until "end" of line (until carriage return)
END IF
Function julian:
Converts characters to ASCII
Calculates a Julian Day
Function temp:
Converts counts into degrees Celsius for temp using a look-up table
APPROPRIATE EQUATIONS
Equation to calculate sigs, refs, time, and temp from decimals:
sigs = (sig dec#1)*256+(sig dec#2)*65,536+(sig dec#3) / 16,777,216
refs = (ref dec#1)*256+(ref dec#2)*65,536+(ref dec #3) / 16,777,216
time = (time decimal #1) + (time decimal #2) * 256
temp = (temp decimal #1) + (temp decimal #2) * 256
Equation to calculate a and c:
c = N(offset) - [4 * ln (csig/cref)]
a = N(offset) - [4 * ln (asig/aref)]
Equation to correct a and c values for internal temperature:
c' = c(meas) + (T(temp) - T0(temp off)) * Kt(temp coeff)
a' = a(meas) + (T(temp) - T0(temp off)) * Kt(temp coeff)
Equation to calculate Julian Day (date + fraction of day):
Julian Day = (date) + {[(hr * 3600) + (min * 60) + (sec)] / 3600} / 24
Complete Time-Series Plots
CMO Deployment 1: 07/08/96 - 09/26/96 (Year Day 190 to 270)
Some corrections were applied to the time-series plots. Internal temperature corrections for both absorption (a) and
beam attenuation (c) coefficients of the WET Labs ac-9 were applied according to factory specifications (see flowchart
for details). The following equation: a715 = a715meas - [0.0029 * (Tmeas - 23.7)], was used in order to correct for in
situ temperature effects for the 715 nm wavelength for the absorption coefficient, where Tmeas is the internal temperature
of the instrument (AC-9 Protocol Manual, 1996). The 13.5 m ac-9 data were fitted for linear trends to remove the effects
caused by bromine solution contamination. Because of the assumptions associated with the usage of generic phytoplankton
cultures in translating voltage into chlorophyll concentration for the calibration of both the WETStar and Sea Tech
fluorometers, offsets were added to WETStar and Sea Tech fluorometer data. The offsets were determined by comparisons
between the BIOPS fluorometer data and profile data of chlorophyll concentration measured by Heidi Sosik at WHOI. ac-9
data were calibrated against ac-9 profile data taken by R. Zaneveld at OSU. Transmissometer beam c data were calibrated
against ac-9 c650 data. Fluorometer data were averaged over 1 hour, and ac-9 data were averaged over 1 hour. The
temperature data presented in the stack plot were averaged over 2 hours. All other sensor data were plotted without
further processing.
Fig. 7: 13.5m PAR, Lu 683, Temp, WETStar Fluor, and Beam c(660)
Fig. 8: 13.5m ac-9
Fig. 9: 37m PAR, Lu 683, Temp, WETStar Fluor, and Beam c(660)
Fig. 10: 37m ac-9
Fig. 11: 52m PAR; Temp; Sea Tech, WETStar Fluor; Beam c(660)
Fig. 12: 52m ac-9
Fig. 13:68m Temp; Sea Tech, WETStar Fluor; and Beam c(660)
Fig. 14: 68m ac-9
Fig. 15: Temperature stack plot
(S, MT, and MD data courtesy of Murray Levine of OSU)
Fig. 16: WETStar Fluor at all depths
Fig. 17: Transmissometer Beam c(660) at all depths
Fig. 18: PAR and Lu 683 at all depths
Below are satellite images of Hurricane Edouard and Hurricane Hortense.
These images were provided by David Porter and Donald Thompson of the
Johns Hopkins University Applied Physics Laboratory.
Fig. 19: Hurricane Edouard Track
Fig. 20: Hurricane Edouard
Fig. 21: Hurricane Hortense Track
Fig. 22: Hurricane Hortense
Fig. 23: Physical and optical effects of the hurricanes
(Wind data courtesy of Steve Lentz of WHOI)
Acknowledgements
The Ocean Physics Laboratory of UCSB would like to thank:
the Office of Naval Research (ONR) for their project support (Grant No. N00014-96-1-0669) and an AASERT award to
Grace Chang; Yogi Agrawal and Chuck Pottsmith of Sequoia Inc. for the use of their bottom tripod; David Porter and
Donald Thompson of JHU/APL for satellite images; the crew of the R/V Oceanus; Murray Levine of OSU for sharing his
mooring; and Erin Lutrick for her help in the assembly of the BIOPS.