Underwater light environment in Arctic fjords

• Published in: Earth System Science Data
• Main Authors: Schlegel, Robert, W, Rakesh Kumar, Singh, Bernard, Gentili, Simon, Bélanger, Laura Castro de La, Guardia, Dorte, Krause-Jensen, Cale A., Miller, Mikael, Sejr, Jean-Pierre, Gattuso
• Other Authors: Laboratoire d'océanographie de Villefranche (LOV), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de la Mer de Villefranche (IMEV), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université du Québec à Rimouski (UQAR), National University of Singapore (NUS), Norwegian Polar Institute, Aarhus University Aarhus, Universiteit Utrecht / Utrecht University Utrecht, Institut du Développement Durable et des Relations Internationales (IDDRI), Institut d'Études Politiques IEP - Paris, European Project: Horizon 2020 #869154,FACE-IT
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2024
• Subjects: [SDE]Environmental Sciences; Arctic; Greenland; Svalbard
• Online Access: https://hal.science/hal-04612075; https://hal.science/hal-04612075/document; https://hal.science/hal-04612075/file/essd-16-2773-2024.pdf; https://doi.org/10.5194/essd-16-2773-2024

International audience Most inhabitants of the Arctic live near the coastline, which includes fjord systems where socio-ecological coupling with coastal communities is dominant. It is therefore critically important that the key aspectsof Arctic fjords be measured as well as possible. Much work has been done to monitor temperature and salinity,but in-depth knowledge of the light environment throughout Arctic fjords is lacking. This is particularly prob-lematic knowing the importance of light for benthic ecosystem engineers such as macroalgae, which also playa major role in ecosystem function. Here we document the creation and implementation of a high-resolution( ∼ 50–150 m) gridded dataset for surface photosynthetically available radiation (PAR), diffuse attenuation ofPAR through the water column (KPAR ), and PAR available at the seafloor (bottom PAR) for seven Arctic fjordsdistributed throughout Svalbard, Greenland, and Norway during the period 2003–2022. In addition to KPARand bottom PAR being available at a monthly resolution over this time period, all variables are available as aglobal average, annual averages, and monthly climatologies, with standard deviations provided for the latter two.Throughout most Arctic fjords, the interannual variability of monthly bottom PAR is too large to determine anylong-term trends. However, in some fjords, bottom PAR increases in spring and autumn and decreases in sum-mer. While a full investigation into these causes is beyond the scope of the description of the dataset presentedhere, it is hypothesized that this shift is due to a decrease in seasonal ice cover (i.e. enhanced surface PAR) inthe shoulder seasons and an increase in coastal runoff (i.e. increased turbidity and decreased surface PAR) insummer. A demonstration of the usability of the dataset is given by showing how it can be combined with knownPAR requirements of macroalgae to track the change in the potential distribution area for macroalgal habitatswithin fjords with time.The datasets are available on PANGAEA ...