A Novel Integration of an Ultraviolet Nitrate Sensor On Board a Towed Vehicle for Mapping Open-Ocean Submesoscale Nitrate Variability

Rosalind Pidcock National Oceanography Centre, Southampton, Southampton, United Kingdom

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Meric Srokosz National Oceanography Centre, Southampton, Southampton, United Kingdom

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John Allen National Oceanography Centre, Southampton, Southampton, United Kingdom

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Mark Hartman National Oceanography Centre, Southampton, Southampton, United Kingdom

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Stuart Painter National Oceanography Centre, Southampton, Southampton, United Kingdom

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Matt Mowlem National Oceanography Centre, Southampton, Southampton, United Kingdom

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David Hydes National Oceanography Centre, Southampton, Southampton, United Kingdom

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Adrian Martin National Oceanography Centre, Southampton, Southampton, United Kingdom

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Abstract

Initial results from a deployment of the SUV-6 ultraviolet spectrophotometer, integrated with the SeaSoar towed vehicle, are presented. The innovative, combined system measures nitrate concentration at high spatial resolution (4 m vertically, 5 km horizontally), high sensitivity (0.2 μM), and concomitantly with temperature, salinity, and dissolved oxygen. The authors demonstrate that this approach constitutes a powerful new tool for quantifying the role of mesoscale and submesoscale vertical nutrient fluxes to the euphotic zone, using measurements from a high-resolution survey of an eddy dipole in the Iceland Basin during the summer of 2007.

Corresponding author address: Rosalind Pidcock, National Oceanography Centre, Southampton (NOCS), University of Southampton Waterfront Campus, European Way, Southampton, SO14 3ZH, United Kingdom. Email: remp103@noc.soton.ac.uk

Abstract

Initial results from a deployment of the SUV-6 ultraviolet spectrophotometer, integrated with the SeaSoar towed vehicle, are presented. The innovative, combined system measures nitrate concentration at high spatial resolution (4 m vertically, 5 km horizontally), high sensitivity (0.2 μM), and concomitantly with temperature, salinity, and dissolved oxygen. The authors demonstrate that this approach constitutes a powerful new tool for quantifying the role of mesoscale and submesoscale vertical nutrient fluxes to the euphotic zone, using measurements from a high-resolution survey of an eddy dipole in the Iceland Basin during the summer of 2007.

Corresponding author address: Rosalind Pidcock, National Oceanography Centre, Southampton (NOCS), University of Southampton Waterfront Campus, European Way, Southampton, SO14 3ZH, United Kingdom. Email: remp103@noc.soton.ac.uk

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