Diffuse downwelling attenuation coefficients for Southern Ocean waters for wavelengths 290-700 nm


Diffuse downwelling attenuation coefficients in Napierian form (DAC down) for Southern Ocean waters for wavelengths 290-700 nm. Coefficients for 320-700 nm were calculated directly from depth profiles of in situ irradiance made with an Ocean Optics Jaz spectrophotometer at PAL-LTER Station B, Arthur Harbor, Antarctica. The station is a 75 m deep sampling location about 1 km offshore. Due to the low signal-to-noise ratio in the in situ irradiance observations at wavelengths < 320 nm, coefficients were estimated for 290-320 nm using an exponential model fit to observed data from the 320-370 nm interval:DAC down =e^(-0.0149 * lamda+3.60)To achieve minimum boat shadow while making the irradiance profile measurements, the fiber optic cable and light sensor (cosine corrector) were streamed away from the small boat in a direction that was both to windward and toward the sun; the boat was then allowed to drift downwind from the measurement location to a suitable stand-off distance. A series of concurrent surface irradiance measurements made with a LI-COR PAR sensor (model LI-193SA; LI-COR Biosciences, Lincoln, NE, USA) was used to correct the spectra made as part of these profiles for any changes in incident light intensity that occurred between measurements.

Version 2, 2018-05-14.

DOI https://doi.org/10.1594/PANGAEA.889858
Related Identifier https://doi.org/10.1594/PANGAEA.879582
Related Identifier https://doi.org/10.1016/j.gca.2018.04.030
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.889858
Creator Collins, James R ORCID logo; Marchetti, Adrian ORCID logo; Ducklow, Hugh W; Van Mooy, Benjamin A S
Publisher PANGAEA
Publication Year 2018
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Resource Type Dataset
Format text/tab-separated-values
Size 3577 data points
Discipline Earth System Research
Spatial Coverage (-64.073 LON, -64.779 LAT); Arthur Harbour, Antarctica