Hyperspectral downward irradiance in air (Es) 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.