Niskin Bottle

CTD/Niskin Rosette bottles

Trace Metal Bottle

Trace Metal (TM) Rosette bottles

1995-02-05

1995-03-14

Methods & Sampling
PI: Robert R. Bidigare of: University of Hawaii dataset: Pigments, HPLC method, sampled from bottle casts dates: March 14, 1995 to April 07, 1995 location: N: 22.4853 S: 9.9994 W: 57.3007 E: 68.7532 cruise: TTN-045, Arabian Sea Process cruise #2 (Spring Intermonsoon) ship: R/V Thomas Thompson

Processing Description
HPLC Pigment methods Method by Wright et al (Mar. Ecol. Prog. Ser. 1991, 77:183-196) CHLA1, CHLA2, CHLB1 and CHLB2 estimated following the method of Latasa et al (Mar. Chem. 1996, 51:315-324) Pigment data for P2 & P5: A comparison of the TURNER-determined chlorophyll a concentrations with the HPLC-determined TOTCHLA concentrations (monovinyl chlorophyll a + divinyl chlorophyll a + monovinyl chlorophyllide a; units = ng Chl a equivalents/L) was performed for Process Cruise #2 (TTN-045) and Process Cruise #5 (TTN-050). While good correlations were obtained for both cruises, the slope obtained for Process Cruise #5 was significantly different from 1 (i.e., TURNER > HPLC). This difference was probably caused by the presence of Chl a-related pigments during Process Cruise #5. Thus, we recommend that whenever possible use the HPLC pigment data and not the TURNER pigment data. If HPLC data is not available for a given cast, we further recommend that you use the following equations to transform the TURNER data into HPLC-equivalent concentrations (cf., Babin, M., A. Morel, H. Claustre, A. Bricaud, Z. Kolber and P.G. Falkowski. 1996. Nitrogen- and irradiance-dependent variations of the maximum quantum yield of carbon fixation in eutrophic, mesotrophic and oligotrophic marine systems. Deep-Sea Research, in press). Results of geometric mean regression analyses (reduced major axis): Y = HPLC TOTCHLA (monovinyl chlorophyll a + divinyl chlorophyll a + monovinyl chlorophyllide a), units = ng Chl a equivalents/L X = TURNER chlorophyll a (it is necessary to convert the Turner Chl a concentrations in the Arabian Sea data base from mg/m3 to ng/L by multiplying concentrations by 1000) (1) Process Cruise #2 (TTN-045) HPLC TOTCHLA = TURNER*(0.975) + 4.833 (r = 0.9822, n = 146) (2) Process Cruise #5 (TTN-050) HPLC TOTCHLA = TURNER*(0.708) + 12.881 (r = 0.9772, n = 575) Robert R. Bidigare Department of Oceanography University of Hawaii Honolulu, HI 96822 808-956-6567 (voice mail) 808-956-9516 (fax)

1995-07-17

Methods & Sampling
PI: Ralf Goericke of: Scripps Institute of Oceanography dataset: Pigments, HPLC method, sampled from bottle casts dates: July 18, 1995 to August 13, 1995 location: N: 22.5001 S: 9.9258 W: 57.2997 E: 68.7507 cruise: TTN-049, Arabian Sea Process cruise 4 (Middle SW Monsoon) ship: R/V Thomas Thompson Methodology Goericke and Repeta (1993), Mar.Ecol.Prog.Ser., 101:307-313

1995-08-18

Methods & Sampling
PI: Robert R. Bidigare of: University of Hawaii dataset: Pigments, HPLC method, sampled from bottle casts dates: August 18, 1995 to September 13, 1995 location: N: 22.4688 S: 9.9991 W: 57.3004 E: 68.7494 cruise: TTN-050, Arabian Sea Process cruise #5 (Late SW Monsoon) ship: R/V Thomas Thompson

Processing Description
HPLC Pigment methods Method by Wright et al (Mar. Ecol. Prog. Ser. 1991, 77:183-196) CHLA1, CHLA2, CHLB1 and CHLB2 estimated following the method of Latasa et al (Mar. Chem. 1996, 51:315-324) Pigment data for P2 & P5: A comparison of the TURNER-determined chlorophyll a concentrations with the HPLC-determined TOTCHLA concentrations (monovinyl chlorophyll a + divinyl chlorophyll a + monovinyl chlorophyllide a; units = ng Chl a equivalents/L) was performed for Process Cruise #2 (TTN-045) and Process Cruise #5 (TTN-050). While good correlations were obtained for both cruises, the slope obtained for Process Cruise #5 was significantly different from 1 (i.e., TURNER > HPLC). This difference was probably caused by the presence of Chl a-related pigments during Process Cruise #5. Thus, we recommend that whenever possible use the HPLC pigment data and not the TURNER pigment data. If HPLC data is not available for a given cast, we further recommend that you use the following equations to transform the TURNER data into HPLC-equivalent concentrations (cf., Babin, M., A. Morel, H. Claustre, A. Bricaud, Z. Kolber and P.G. Falkowski. 1996. Nitrogen- and irradiance-dependent variations of the maximum quantum yield of carbon fixation in eutrophic, mesotrophic and oligotrophic marine systems. Deep-Sea Research, in press). Results of geometric mean regression analyses (reduced major axis): Y = HPLC TOTCHLA (monovinyl chlorophyll a + divinyl chlorophyll a + monovinyl chlorophyllide a), units = ng Chl a equivalents/L X = TURNER chlorophyll a (it is necessary to convert the Turner Chl a concentrations in the Arabian Sea data base from mg/m3 to ng/L by multiplying concentrations by 1000) (1) Process Cruise #2 (TTN-045) HPLC TOTCHLA = TURNER*(0.975) + 4.833 (r = 0.9822, n = 146) (2) Process Cruise #5 (TTN-050) HPLC TOTCHLA = TURNER*(0.708) + 12.881 (r = 0.9772, n = 575) Robert R. Bidigare Department of Oceanography University of Hawaii Honolulu, HI 96822 808-956-6567 (voice mail) 808-956-9516 (fax)

1995-10-29

Methods & Sampling
PI: Robert R. Bidigare of: University of Hawaii dataset: Pigments, HPLC method, sampled from bottle casts dates: October 29, 1995 to November 25, 1995 location: N: 24.3302 S: 10.0823 W: 56.4858 E: 67.1666 cruise: TTN-053, Arabian Sea Process cruise #6 (bio-optics) ship: R/V Thomas Thompson

Processing Description
HPLC Pigment methods - Process 6 Robert Bidigare University of Hawaii References: 1. Wright et al (Mar. Ecol. Prog. Ser. 1991, 77:183-196) 2. Latasa et al (Mar. Chem. 1996, 51:315-324) - estimates of chl_a1, chl_a2, chl_b1 and chl_b2 Methodology notes for the P6 pigment data: I) A comparison of the TURNER-determined chlorophyll a concentrations with the HPLC-determined TOTCHLA concentrations (monovinyl chlorophyll a + divinyl chlorophyll a + monovinyl chlorophyllide a; units = ng Chl a equivalents/L) was performed for Process Cruise #6 (TTN-053). While a slope of approximately of 1 was obtained (see below), there was a significant amount of scatter in the cross-plot (r = 0.938). This scatter was probably caused in part by the variable presence of Chl accessory pigments which interfere with the fluorometric method. Thus, we recommend that whenever possible use the HPLC pigment data and not the TURNER pigment data. If HPLC data is not available for a given cast, we further recommend that you use the following equation to transform the TURNER data into HPLC-equivalent concentrations (cf., Babin, M., A. Morel, H. Claustre, A. Bricaud, Z. Kolber and P.G. Falkowski. 1996. Nitrogen- and irradiance-dependent variations of the maximum quantum yield of carbon fixation in eutrophic, mesotrophic and oligotrophic marine systems. Deep-Sea Research, in press). Results of geometric mean regression analyses (reduced major axis): Y = HPLC TOTCHLA (monovinyl chlorophyll a + divinyl chlorophyll a + monovinyl chlorophyllide a), units = ng Chl a equivalents/L X = TURNER chlorophyll a (it is necessary to convert the Turner Chl a concentrations in the Arabian Sea data base from mg/m3 to ng/L by multiplying concentrations by 1000) Process Cruise #6 (TTN-053) HPLC TOTCHLA = TURNER*(1.052) - 56.474 (r = 0.938, n = 479) II) Accessory pigment quantification (1) Although most pigment peaks were clearly identifiable based on retention time, a few of the minor pigments presented difficulties. The presence of lutein, in particular, was difficult to determine unambiguously. Lutein concentrations are therefore specified only where that peak is clearly evident, although it may be present in trace quantities in other samples as well. (2) The peak identified as alloxanthin agreed very well with a concurrently run standard for approximately the first half of the samples run. However, in samples run later, what appears to be the same peak does not agree well with the known alloxanthin retention time. Since samples were run in random order and because there is no particular reason for the sudden absence of the pigment, we continued to identify this peak as alloxanthin throughout the remainder of the data set. The appearance of the peak as a doublet in some instances suggests the possibility of pigment alteration (e.g., a trans to cis isomerization). The change in agreement between sample and standard alloxanthin peaks also corresponds with a change in the HPLC column, though this does not appear to have affected the comparability of other peaks with their standards. (3) Chlorophyll b occasionally appeared as a split peak, or with a very close shoulder on the main peak (either leading or trailing). This may have resulted from either a partial separation of monovinyl and divinyl chlorophyll b, or from the coelution of some other pigment with chlorophyll b. In all cases where this occurred, both peaks (or peak with shoulder) were included in the area used to calculate chlorophyll b concentrations.

1995-11-30

Methods & Sampling
PI: Ralf Goericke of: University of California, San Diego dataset: Pigments, HPLC method, sampled from bottle casts dates: November 30, 1995 to December 26, 1995 location: N: 22.5171 S: 9.9789 W: 57.2992 E: 68.7849 project/cruise: Arabian Sea/TTN-054, Process cruise 7 (Early NE Monsoon) ship: R/V Thomas Thompson Methodology Goericke and Repeta (1993), Mar.Ecol.Prog.Ser., 101:307-313