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

• Main Authors: Collins, James R, Marchetti, Adrian, Ducklow, Hugh W, Van Mooy, Benjamin A S
• Format: Dataset
• Language: English
• Published: PANGAEA 2018
• Subjects: Wavelength; Diffuse attenuation coefficient, downward; Diffuse attenuation coefficient, downward, standard deviation; Monitoring station; Arthur Harbor; Southern Ocean; Antarc*; Antarctica
• Online Access: https://dx.doi.org/10.1594/pangaea.889858; https://doi.pangaea.de/10.1594/PANGAEA.889858

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 ... : Version 2, 2018-05-14. ...