@article{6094772850f64ea589acf3d59ae5c2cd,
title = "Upwelling Irradiance below Sea Ice—PAR Intensities and Spectral Distributions",
abstract = "Upwelling and downwelling spectral (320–920 nm) distributions and photosynthetic active radiation (PAR) intensities were measured below a first-year land-fast sea ice in a western Greenland fjord with and without a snow cover. Time-series of surface upwelling PAR, downwelling PAR, and under-ice PAR were also obtained. Spectral distributions of upwelling and downwelling irradiances were similar except for reduced intensities in the UV, the red, and NIR parts of the spectrum when the ice was snow-covered. Upwelling PAR amounted to about 10% of downwelling intensities, giving 5.1 µmol photons m−2 s−1 at the bottom of the ice with a snow cover and 8.2 µmol photons m−2 s−1 without. PAR partitioning analyses showed that the upwelling was related to scattering by suspended particles in the water column. A snow melt increased under-ice daily maximum downwelling PAR from 50 to 180 µmol photons m−2 s−1 and overall under-ice PAR of 55 and 198 µmol photons m−2 s−1 with 10% upwelling. It is concluded that upwelling PAR below sea ice might be an important factor regarding sea ice algae photophysiology and performance with a 10% higher PAR; specifically when PAR > Ek the light saturation point of the sea ice algae.",
keywords = "Greenland, Low light adapted ice algae, PAR, Sea ice, Upwelling and downwelling irradiances",
author = "Lund-Hansen, {Lars Chresten} and Michael Bjerg-Nielsen and Tanja Stratmann and Ian Hawes and Sorrell, {Brian K.}",
note = "Funding Information: Funding: This project was funded by the Danish Council for Independent Research (Project DFF–1323-00335: Sea ice ecosystems: Ecological effects of a thinning snow cover), the New Zealand Min-istry of Business, Innovation and Employment (Project ANTA1801), the Carlsberg Foundation, Aar-hus University, and the Hartmann Brothers Foundation and was developed in the frame of the pro-ject FACE-IT (The Future of Arctic Coastal Ecosystems—Identifying Transitions in Fjord Systems and Adjacent Coastal Areas). FACE-IT has received funding from the European Union{\textquoteright}s Horizon 2020 research and innovation program under grant agreement No 869154. Funding Information: This project was funded by the Danish Council for Independent Research (Project DFF?1323-00335: Sea ice ecosystems: Ecological effects of a thinning snow cover), the New Zealand Ministry of Business, Innovation and Employment (Project ANTA1801), the Carlsberg Foundation, Aarhus University, and the Hartmann Brothers Foundation and was developed in the frame of the pro-ject FACE-IT (The Future of Arctic Coastal Ecosystems?Identifying Transitions in Fjord Systems and Adjacent Coastal Areas). FACE-IT has received funding from the European Union?s Horizon 2020 research and innovation program under grant agreement No 869154. Publisher Copyright: {\textcopyright} 2021 by the authors. Licensee MDPI, Basel, Switzerland.",
year = "2021",
month = aug,
doi = "10.3390/jmse9080830",
language = "English",
volume = "9",
pages = "1--12",
journal = "Journal of Marine Science and Engineering",
issn = "2077-1312",
publisher = "Multidisciplinary Digital Publishing Institute",
number = "8",
}