In April 2017, two Ice Atmosphere Arctic Ocean Observing System platforms (IAOOS 23 and IAOOS 24) were deployed near the North Pole. Over the next 8 months, they meandered southwards with the ice in the Transpolar Drift, collecting measurements in the upper 250 m of Amundsen Basin, Nansen Basin and Fram Strait. The ocean profilers are PROVOR SPI (from French manufacturer NKE), which includes a Seabird SBE41 CTD (Conductivity, Temperature, Depth) and a dissolved oxygen (DO) Aandera 4330 optode. IAOOS 23 also featured a bio-optics sensor suite and a submersible ultraviolet nitrate analyzer (SUNA, Satlantic-Seabird Inc.). The bio-optics sensor suite (called Pack Rem A) combines a three-optical-sensor instrument (ECO Triplet, WET Labs Inc.) and a multispectral radiometer (OCR-504, Satlantic Inc.). The present dataset is composed of chlorophyll-a fluorescence, backscatter, irradiances (at 412, 490 and 555 nm), photosynthetically active radiation (PAR), nitrate and colored-dissolved organic matter data from the IAOOS 23 platform, as well as composites of absolute salinity, conservative temperature and apparent oxygen utilization data from both profilers. The profilers were set to perform two upward profiles a day from 250 m starting at approximately 6 am and 6 pm. In this dataset, chlorophyll-a, PAR and irradiances were corrected with a shift to set dark values to zero. Nitrate was interpolated vertically every 5 m, and all other parameters were interpolated vertically every 0.5 m.

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