Spectrophotometric measurements of absorption coefficients by phytoplankton during RV POLARSTERN cruise PS121 from 11 Aug to 10 Sep 2019 ...

• Main Authors: Bracher, Astrid, Liu, Yangyang, Wiegmann, Sonja
• Format: Dataset
• Language: English
• Published: PANGAEA 2021
• Subjects: absorption; Fram Strait; inherent optical properties; North Sea; particulate matter; Phytoplankton; Event label; DATE/TIME; Sample ID; LATITUDE; LONGITUDE; DEPTH, water; Sample volume; Absorption coefficient, phytoplankton, at 350 nm; Absorption coefficient, phytoplankton, at 352 nm; Absorption coefficient, phytoplankton, at 354 nm; Absorption coefficient, phytoplankton, at 356 nm; Absorption coefficient, phytoplankton, at 358 nm; Absorption coefficient, phytoplankton, at 360 nm; Absorption coefficient, phytoplankton, at 362 nm; Absorption coefficient, phytoplankton, at 364 nm; Absorption coefficient, phytoplankton, at 366 nm; Absorption coefficient, phytoplankton, at 368 nm; Absorption coefficient, phytoplankton, at 370 nm; Absorption coefficient, phytoplankton, at 372 nm; Absorption coefficient, phytoplankton, at 374 nm; Absorption coefficient, phytoplankton, at 376 nm; Absorption coefficient, phytoplankton, at 378 nm; Absorption coefficient, phytoplankton, at 380 nm; Absorption coefficient, phytoplankton, at 382 nm; Absorption coefficient, phytoplankton, at 384 nm; Absorption coefficient, phytoplankton, at 386 nm; Absorption coefficient, phytoplankton, at 388 nm; Absorption coefficient, phytoplankton, at 390 nm; Absorption coefficient, phytoplankton, at 392 nm; Absorption coefficient, phytoplankton, at 394 nm; Absorption coefficient, phytoplankton, at 396 nm; Absorption coefficient, phytoplankton, at 398 nm; Absorption coefficient, phytoplankton, at 400 nm; Absorption coefficient, phytoplankton, at 402 nm; Absorption coefficient, phytoplankton, at 404 nm; Absorption coefficient, phytoplankton, at 406 nm; Absorption coefficient, phytoplankton, at 408 nm; Absorption coefficient, phytoplankton, at 410 nm; Absorption coefficient, phytoplankton, at 412 nm; Absorption coefficient, phytoplankton, at 414 nm; Absorption coefficient, phytoplankton, at 416 nm; Absorption coefficient, phytoplankton, at 418 nm; Absorption coefficient, phytoplankton, at 420 nm; Absorption coefficient, phytoplankton, at 422 nm
• Online Access: https://dx.doi.org/10.1594/pangaea.938260; https://doi.pangaea.de/10.1594/PANGAEA.938260

Water samples were taken during North Sea to Fram Strait expedition PS121 with RV Polarstern from 11 Aug to 10 Sep 2019. Water samples were collected from CTD Niskin bottles at five to six different depths from the upper 100 m and additionally from the ship's seawater supply pumped through teflon tubing from about 11m depth during underway as described in Liu et al (2018). All collected samples were filtered through 25 cm Whatman GF/F filters, respectively, under low-vacuum pressure (below 200 mbar). Blank filters were collected by soaking them in 0.2um filtered seawater. Measurements for particulate and non-algal (NAP) absorption were performed directly after filtration the quantitative filtration techniques-intergrative cavity measurement device and procedure from Röttgers et al. (2016) as described in Liu et al. (2018). Phytoplankton absorption (aph) was derived by subtracting the NAP (Bracher et al. 2021) from the particulate absorption. ... : Further specifications on the measurements:a) Instrument: light source: UV-VIS lamp (CF-1000- HC lamp, Illumination Technology, USA); absorption meter: Quantitative Filter Technique - Integrating Cavity Absorption Meter (QFT-ICAM) (Röttgers et al., 2016) with 80 mm- diameter integrating sphere; detector: photodiode array spectrometer (AVASPEC-ULS2048-RS-USB2, Avantes, the Netherlands).b) wavelength range of scan and resolution: 313.5-875.7 nm, 0.3 nm.c) slit band width: 2 nm.d) sample filters were bleached with 10% sodium hypochlorite (NaClO) solution for the OD measurement of NAP.e) samples were measured for four times and bleached samples were measured twice.f) dark current and blank filters were measured and subtracted.Further specifications about data analysis:a) interpolated wavelength range and resolution: 320-844 nm, 2nm.b) wavelength range for fluorescence correction: 670:800 nm.c) diameter of sample patch on GF/F filter: 2.133 cm.d) pathlength amplification factor (beta correction factor): 4.06 ...