HOT-304 KOK1807 Optics - LISST, C-Star, AC-S, ECO

These Simons Collaboration on Ocean Processes and Ecology (SCOPE) data products were produced by the University of Hawaiʻi at Mānoa with support from the Simons Foundation. Four biooptical instruments were plumbed to the underway uncontaminated seawater on the R/V KOK for the HOT-304 cruise to Station ALOHA in the north Pacific Ocean. Data for each instrument were averaged to the minute and matched to a timestamp on the minute. LISST: Filtered values (<0.2 um) removed from all data. The summed volume concentration of particles (in uL/L) are converted to carbon concentrations (umol C /L) using Mender-Deuer and Lessard (2000) conversion factor and is presented for 3 size ranges: 1.35-2 µm, 2-20 µm, and 20-100 µm. Particle volume concentration can be converted to particle concentration by assuming spherical particles. The total particle concentration (#/L) is calculated for particles with a diameter between 1.35 and 100 um. Larger size classes are excluded due to low detection limits and scattering at density gradients. Note that data have not been processed to remove outliers. C-star: beam attenuation coefficient at 650 nm with filtered values (<0.2 um) removed. AC-S: Filtered values (<0.2 um) removed from all data (see White et al., 2017, GRL); data corrected for residual temperature and scattering; AC-S chl a concentrations obtained from a Gaussian fit over absorbance spectra in the red portion of the spectrum, assuming in vivo chl-a specific absorption of 0.0203 m2/mg at 674 nm. Beam attenuation coefficient is presented from 650nm. ECO: filtered values (<0.2 um) removed from chl and volume scattering data; chl fluorescence converted to mg/m3 using factory calibrations. The volume scattering is converted to particle backscattering coefficient following Boss and Pegau (2001). The timestamp is in UTC.西蒙海洋过程与生态合作研究（Simons Collaboration on Ocean Processes and Ecology, SCOPE）的数据产品由夏威夷大学马诺阿分校制作，得到西蒙基金会（Simons Foundation）资助。 在北太平洋ALOHA站位开展的HOT-304航次中，研究团队将四台生物光学仪器接驳至KOK号科考船（R/V KOK）的走航未受污染海水系统。每台仪器的采集数据均按分钟取平均，并与整分钟时间戳完成匹配。 LISST仪器：所有数据均已剔除<0.2 μm的过滤组分对应数值。颗粒总容积浓度（单位：μL/L）采用Mender-Deuer与Lessard（2000）提出的转换系数，转换为碳浓度（单位：μmol C/L），并按3个粒径分级呈现：1.35~2 μm、2~20 μm以及20~100 μm。若假设颗粒为球形，可将颗粒容积浓度转换为颗粒数浓度；据此计算得到直径介于1.35~100 μm的颗粒总浓度（单位：#/L）。由于检测限偏低且密度梯度处存在散射干扰，更大粒径的分级数据已被剔除。请注意，本数据集未经过异常值剔除处理。 C-star仪器：650 nm处的光束衰减系数，所有数据均已剔除<0.2 μm的过滤组分对应数值。 AC-S仪器：所有数据均已剔除<0.2 μm的过滤组分对应数值（详见White等人2017年发表于《地球物理研究快报》（Geophysical Research Letters, GRL）的研究）；数据已针对残余温度与散射效应完成校正。AC-S叶绿素a浓度通过对光谱红光波段的吸光度光谱进行高斯拟合得到，假设活体叶绿素a在674 nm处的比吸收系数为0.0203 m²/mg。光束衰减系数以650 nm为基准呈现。 ECO仪器：叶绿素与容积散射数据均已剔除<0.2 μm的过滤组分对应数值；叶绿素荧光值通过工厂校准系数转换为mg/m³单位。容积散射数据依据Boss与Pegau（2001）提出的方法转换为粒子后向散射系数。所有时间戳均采用协调世界时（UTC）。