Measurements of solar radiation over and under sea ice have been performed on various stations in the Arctic Ocean during various Polarstern cruises between 2011 and 2017. All radiation measurements have been performed with Ramses spectral radiometers (Trios, Rastede, Germany). All data are given in full spectral resolution interpolated to 1.0 nm, and integrated over the entire wavelength range (broadband, total: 320 to 950 nm). One sensor was mounted on a Remotely Operated Vehicle (ROV) and one radiometer was installed on the sea ice for surface reference measurements (solar irradiance). Under-ice measurements are corrected for the amount of water between the sensor and the ice-water interface. Transmittance was calculated as the ratio of incident and transmitted irradiance. Along with the radiation measurements, ROV positions were obtained from acoustic USBL-positioning and sea ice draft determined from vehicle depth and the distance to the ice measured by a sonar altimeter. ROV-Attitude and position measurements are used for quality control and spatial resampling of the dataset. All times are given in UTC.

Supplement to: Katlein, Christian; Arndt, Stefanie; Belter, Hans Jakob; Castellani, Giulia; Nicolaus, Marcel (2019): Seasonal Evolution of Light Transmission Distributions Through Arctic Sea Ice. Journal of Geophysical Research: Oceans, 124(8), 5418-5435