title: Laterally spreading iron, humic-like dissolved organic matter and nutrients in cold, dense subsurface water of the Arctic Ocean.
abstract: The location and magnitude of oceanic iron sources remain uncertain owing to a scarcity of data, particularly in the Arctic Ocean. The formation of cold, dense water in the subsurface layer of the western Arctic Ocean is a key process in the lateral transport of iron, macronutrients, and other chemical constituents. Here, we present iron, humic-like fluorescent dissolved organic matter, and nutrient concentration data in waters above the continental slope and shelf and along two transects across the shelf-basin interface in the western Arctic Ocean. We detected high concentrations in shelf bottom waters and in a plume that extended in the subsurface cold dense water of the halocline layer in slope and basin regions. At σθ = 26.5, dissolved Fe, humic-like fluorescence intensity, and nutrient maxima coincided with N* minima (large negative values of N* indicate significant denitrification within shelf sediments). These results suggest that these constituents are supplied from the shelf sediments and then transported laterally to basin regions. Humic dissolved organic matter probably plays the most important role in the subsurface maxima and lateral transport of dissolved Fe in the halocline layer as natural Fe-binding organic ligand.
authors.affiliation: Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan.
authors.forename: Nanako
authors.initials: N
authors.lastname: Hioki
authors.affiliation: Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan.
authors.forename: Kenshi
authors.initials: K
authors.lastname: Kuma
authors.affiliation: Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan.
authors.forename: Yuichirou
authors.initials: Y
authors.lastname: Morita
authors.affiliation: Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan.
authors.forename: Ryouhei
authors.initials: R
authors.lastname: Sasayama
authors.affiliation: Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ooki
authors.affiliation: National Institute of Polar Research, Tachikawa 190-8518, Japan.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Kondo
authors.affiliation: Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa 277-8564, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Obata
authors.affiliation: Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0189, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Nishioka
authors.affiliation: Faculty of Environmental Earth Science, Hokkaido University, Sapporo 060-0810, Japan.
authors.forename: Youhei
authors.initials: Y
authors.lastname: Yamashita
authors.affiliation: Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokosuka 237-0061, Japan.
authors.forename: Shigeto
authors.initials: S
authors.lastname: Nishino
authors.affiliation: Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokosuka 237-0061, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kikuchi
authors.affiliation: 1] Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokosuka 237-0061, Japan [2] Institute of Environmental Radioactivity, Fukushima University, Fukushima 960-1296, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Aoyama