Hyperspectral upward radiance in water (Lu) measured during the cruise SO290 with RV SONNE

Data presented here were collected during the cruise SO290 with RV SONNE from Nuoméa (New Caledonia) to Nuoméa (New Caledonia) (April 15, 2022 - Mai, 12, 2022). In total, 19 underwater light profiles were collected at 7 stations, using a free-falling hyperspectral light profiler. The system used was a SEABIRD HyperPro II (SN 099, former Satlantic), equipped with a irradiance sensor to measure downward irradiance in water (Ed, SN 262) and a radiance sensor for the upward radiance in water (Lu, SN 227). A reference unit was attached to the ship to measure the downward irradiance in air (Es, SN 223). The sensors were pre-calibrated by the manufacturer and validated prior to the cruise with a reference lamp. Data were recorded with the SatView software (V 2.9.5_7) and processed from raw to Level1, 1b, 2, 2s to Level 3a using the ProSoft Processing software (V 7.7.19_2). Measured data were binned in 0.5 m depth intervals. A dark correction was made automatically based on shutter measurements by the instrument. Measurements with a tilt higher than 5 were not taken into account during processing. Spectra were interpolated to 1 nm intervals. For each station the hyperspectral profiles for each parameter cover the wavelength range from 400-700 nm, for Ed and Es in [W/m nm], for Lu in [W/m nm sr]. For Ed, Lu and Es descriptive statistics are given including min, max, mean, median and standard deviation of the tilt and the photosynthetically active radiation PAR [µmol photons/m² s (sr)], integrated from 400 - 700 nm. To allow an assignment of above water conditions to the respective depth measurements, Es spectra were given as a function of depth, recalculated from data Level2s. The Profiler measurements were only conducted during daylight. Raw data are available on request from the principal investigator.

本数据集采集自SONNE号科考船（RV SONNE）执行的SO290航次，航行路线为从努美阿（新喀里多尼亚）出发并返回努美阿（新喀里多尼亚），航次时间为2022年4月15日至2022年5月12日。本次航次共在7个站位布设自由下落式高光谱光照剖面仪（free-falling hyperspectral light profiler），累计获取19组水下光照剖面数据。本次使用的观测系统为SEABIRD HyperPro II（序列号099，原属Satlantic公司），该系统搭载了水下下行辐照度传感器（Ed，序列号262）与水下上行辐亮度传感器（Lu，序列号227）。科考船舷侧搭载了参考单元，用于测量大气下行辐照度（Es，序列号223）。所有传感器均由厂商完成预校准，并在航次前通过参考灯进行了现场验证。观测数据通过SatView软件（版本2.9.5_7）进行记录，并使用ProSoft Processing软件（版本7.7.19_2）完成从原始数据到Level1、1b、2、2s再到Level3a的逐级处理。实测数据以0.5米为深度间隔进行分箱处理。仪器通过快门测量自动完成暗电流校正。数据处理阶段将剔除倾斜角大于5的观测结果。光谱数据被插值至1纳米的间隔分辨率。各站位的各参数高光谱剖面的波长覆盖范围均为400~700纳米，其中Ed与Es的单位为[W/(m²·nm)]，Lu的单位为[W/(m²·nm·sr)]。针对Ed、Lu与Es三类数据，本数据集提供了倾斜角与光合有效辐射（photosynthetically active radiation，PAR）的描述性统计量，包括最小值、最大值、均值、中位数与标准差；其中PAR为400~700纳米波段积分得到的光合有效辐射，单位为[μmol photons/(m²·s·sr)]。为实现水面大气条件与对应深度水下观测的匹配关联，本数据集提供了基于Level2s数据重新计算得到的、以深度为变量的Es光谱数据。剖面仪观测仅在日间开展。原始数据可向项目首席研究员申请获取。