scholarly journals Arctic Deep Water Ferromanganese‐Oxide Deposits Reflect the Unique Characteristics of the Arctic Ocean

2017 ◽  
Vol 18 (11) ◽  
pp. 3771-3800 ◽  
Author(s):  
James R. Hein ◽  
Natalia Konstantinova ◽  
Mariah Mikesell ◽  
Kira Mizell ◽  
Jessica N. Fitzsimmons ◽  
...  
Keyword(s):  
Arctic Ocean ◽  
Deep Water ◽  
The Arctic ◽  
The Arctic Ocean

The contribution of the Greenland and Barents seas to the deep water of the Arctic Ocean

1983 ◽  
Vol 88 (C10) ◽  
pp. 5981 ◽  
Author(s):  
James H. Swift ◽  
Taro Takahashi ◽  
Hugh D. Livingston
Keyword(s):  
Arctic Ocean ◽  
Deep Water ◽  
The Arctic ◽  
The Arctic Ocean

scholarly journals Deep water circulation and composition in the Arctic Ocean by dissolved barium, aluminium and silicate

2012 ◽  
Vol 132-133 ◽  
pp. 56-67 ◽  
Author(s):  
T. Roeske ◽  
M. Rutgers vd Loeff ◽  
R. Middag ◽  
K. Bakker
Keyword(s):  
Arctic Ocean ◽  
Deep Water ◽  
Water Circulation ◽  
The Arctic ◽  
The Arctic Ocean

scholarly journals Deep-Water Flow over the Lomonosov Ridge in the Arctic Ocean

2005 ◽  
Vol 35 (8) ◽  
pp. 1489-1493 ◽  
Author(s):  
M-L. Timmermans ◽  
P. Winsor ◽  
J. A. Whitehead
Keyword(s):  
Arctic Ocean ◽  
Deep Water ◽  
Thermohaline Circulation ◽  
Global Climate ◽  
Volume Flow Rate ◽  
The Arctic ◽  
Lomonosov Ridge ◽  
Geothermal Heat ◽  
The Arctic Ocean ◽  
Canadian Basin

Abstract The Arctic Ocean likely impacts global climate through its effect on the rate of deep-water formation and the subsequent influence on global thermohaline circulation. Here, the renewal of the deep waters in the isolated Canadian Basin is quanitified. Using hydraulic theory and hydrographic observations, the authors calculate the magnitude of this renewal where circumstances have thus far prevented direct measurements. A volume flow rate of Q = 0.25 ± 0.15 Sv (Sv ≡ 106 m3 s−1) from the Eurasian Basin to the Canadian Basin via a deep gap in the dividing Lomonosov Ridge is estimated. Deep-water renewal time estimates based on this flow are consistent with 14C isolation ages. The flow is sufficiently large that it has a greater impact on the Canadian Basin deep water than either the geothermal heat flux or diffusive fluxes at the deep-water boundaries.

scholarly journals Elevated sources of cobalt in the Arctic Ocean

2020 ◽  
Author(s):  
Randelle M. Bundy ◽  
Alessandro Tagliabue ◽  
Nicholas J. Hawco ◽  
Peter L. Morton ◽  
Benjamin S. Twining ◽  
...  
Keyword(s):  
Arctic Ocean ◽  
North Atlantic ◽  
Deep Water ◽  
Deep Ocean ◽  
The Arctic ◽  
Biogeochemical Model ◽  
Shelf Area ◽  
The North ◽  
The Arctic Ocean ◽  
High Concentrations

Abstract. Cobalt (Co) is an important bioactive trace metal that can limit or co-limit phytoplankton growth in many regions of the ocean. Total dissolved and labile Co measurements in the Canadian sector of the Arctic Ocean during U.S. GEOTRACES Arctic expedition (GN01) and the Canadian International Polar Year-GEOTRACES expedition (GIPY14) revealed a dynamic biogeochemical cycle for Co in this basin. The major sources of Co in the Arctic were from shelf regions and rivers, with only minimal contributions from other freshwater sources (sea ice, snow) and aeolian deposition. The most striking feature was the extremely high concentrations of dissolved Co in the upper 100 m, with concentrations routinely exceeding 800 pmol L−1 over the shelf regions. This plume of high Co persisted throughout the Arctic basin and extended to the North Pole, where sources of Co shifted from primarily shelf-derived to riverine, as freshwater from Arctic rivers was entrained in the Transpolar Drift. Dissolved Co was also strongly organically-complexed in the Arctic, ranging from 70–100 % complexed in the surface and deep ocean, respectively. Deep water concentrations of dissolved Co were remarkably consistent throughout the basin (~ 55 pmol L−1), with concentrations reflecting those of deep Atlantic water and deep ocean scavenging of dissolved Co. A biogeochemical model of Co cycling was used to support the hypothesis that the majority of the high surface Co in the Arctic was emanating from the shelf. The model showed that the high concentrations of Co observed along the transect were due to the large shelf area of the Arctic, as well as dampened scavenging of Co by manganese (Mn)-oxidizing bacteria due to the lower temperatures. The majority of this scavenging appears to have occurred in the upper 200 m, with minimal additional scavenging below this depth. Preliminary evidence suggests that both dissolved and labile Co are increasing over time on the Arctic shelf, and the elevated surface concentrations of Co likely leads to a net flux of Co out of the Arctic, with implications for downstream biological uptake of Co in the North Atlantic and elevated Co in North Atlantic Deep Water. Understanding the current distributions of Co in the Arctic will be important for constraining changes to Co inputs resulting from regional intensification of freshwater fluxes from ice and permafrost melt in response to ongoing climate change.

scholarly journals A High‐Resolution Geomagnetic Relative Paleointensity Record From the Arctic Ocean Deep‐Water Gateway Deposits During the Last 60 kyr

2019 ◽  
Author(s):  
Chiara Caricchi ◽  
Renata Giulia Lucchi ◽  
Leonardo Sagnotti ◽  
Patrizia Macrì ◽  
Alessio Di Roberto ◽  
...  
Keyword(s):  
High Resolution ◽  
Arctic Ocean ◽  
Deep Water ◽  
The Arctic ◽  
The Arctic Ocean ◽  
Relative Paleointensity

scholarly journals New Constraints on the Physical and Biological Controls on the Silicon Isotopic Composition of the Arctic Ocean

2021 ◽  
Vol 8 ◽  
Author(s):  
Mark A. Brzezinski ◽  
Ivia Closset ◽  
Janice L. Jones ◽  
Gregory F. de Souza ◽  
Colin Maden
Keyword(s):  
Isotopic Composition ◽  
Arctic Ocean ◽  
Silicic Acid ◽  
Deep Water ◽  
Canada Basin ◽  
The Arctic ◽  
Silicon Isotope ◽  
Deep Waters ◽  
The Arctic Ocean ◽  
Source Waters

The silicon isotope composition of silicic acid, δ30Si(OH)4, in the deep Arctic Ocean is anomalously heavy compared to all other deep ocean basins. To further evaluate the mechanisms leading to this condition, δ30Si(OH)4 was examined on US GEOTRACES section GN01 from the Bering Strait to the North Pole. Isotope values in the polar mixed layer showed a strong influence of the transpolar drift. Drift waters contained relatively high [Si(OH)4] with heavy δ30Si(OH)4 consistent with the high silicate of riverine source waters and strong biological Si(OH)4 consumption on the Eurasian shelves. The maximum in silicic acid concentration, [Si(OH)4], within the double halocline of the Canada Basin formed a local minimum in δ30Si(OH)4 that extended across the Canada Basin, reflecting the high-[Si(OH)4] Pacific source waters and benthic inputs of Si(OH)4 in the Chukchi Sea. δ30Si(OH)4 became lighter with the increase in [Si(OH)4] in intermediate and deep waters; however, both Canada Basin deep water and Eurasian Basin deep water were heavier than deep waters from other ocean basins. A preliminary isotope budget incorporating all available Arctic δ30Si(OH)4 data confirms the importance of isotopically heavy inflows in creating the anomalous deep Arctic Si isotope signature, but also reveals a surprising similarity in the isotopic composition of the major inflows compared to outflows across the main gateways connecting the Arctic with the Pacific and the Atlantic. This similarity implies a major role of biological productivity and opal burial in removing light isotopes entering the Arctic Ocean from rivers.

scholarly journals On the 14C and 39Ar Distribution in the Central Arctic Ocean: Implications for Deep Water Formation

Radiocarbon ◽  
1994 ◽  
Vol 36 (3) ◽  
pp. 327-343 ◽  
Author(s):  
Peter Schlosser ◽  
Bernd Kromer ◽  
Gote Östlund ◽  
Brenda Ekwurzel ◽  
Gerhard Bönisch ◽  
...  
Keyword(s):  
Arctic Ocean ◽  
Deep Water ◽  
Atlantic Water ◽  
The Arctic ◽  
Central Arctic Ocean ◽  
Deep Waters ◽  
The Arctic Ocean ◽  
Bottom Waters ◽  
Eurasian Basin ◽  
Canadian Basin

We present ΔA14C and 39Ar data collected in the Nansen, Amundsen and Makarov basins during two expeditions to the central Arctic Ocean (RV Polarstern cruises ARK IV/3, 1987 and ARK VIII/3, 1991). The data are used, together with published Δ14C values, to describe the distribution of Δ14C in all major basins of the Arctic Ocean (Nansen, Amundsen, Makarov and Canada Basins), as well as the 39Ar distribution in the Nansen Basin and the deep waters of the Amundsen and Makarov Basins. From the combined Δ14C and 39Ar distributions, we derive information on the mean “isolation ages” of the deep and bottom waters of the Arctic Ocean. The data point toward mean ages of the bottom waters in the Eurasian Basin (Nansen and Amundsen Basins) of ca. 250-300 yr. The deep waters of the Amundsen Basin show slightly higher 3H concentrations than those in the Nansen Basin, indicating the addition of a higher fraction of water that has been at the sea surface during the past few decades. Correction for the bomb 14C added to the deep waters along with bomb 3H yields isolation ages for the bulk of the deep and bottom waters of the Amundsen Basin similar to those estimated for the Nansen Basin. This finding agrees well with the 39Ar data. Deep and bottom waters in the Canadian Basin (Makarov and Canada Basins) are very homogeneous, with an isolation age of ca. 450 yr. Δ14C and 39Ar data and a simple inverse model treating the Canadian Basin Deep Water (CBDW) as one well-mixed reservoir renewed by a mixture of Atlantic Water (29%), Eurasian Basin Deep Water (69%) and brine-enriched shelf water (2%) yield a mean residence time of CBDW of ca. 300 yr.

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