Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Biogeochemical cycling in the Bering Sea over the onset of major Northern Hemisphere Glaciation

Swann, George E.A., Snelling, Andrea, M. and Pike, Jennifer 2016. Biogeochemical cycling in the Bering Sea over the onset of major Northern Hemisphere Glaciation. Paleoceanography 31 , pp. 1261-1269. 10.1002/2016PA002978

[img]
Preview
PDF - Published Version
Download (832kB) | Preview

Abstract

The Bering Sea is one of the most biologically productive regions in the marine system and plays a key role in regulating the flow of waters to the Arctic Ocean and into the subarctic North Pacific Ocean. Cores from IODP Expedition 323 to the Bering Sea provide the first opportunity to obtain reconstructions from the region that extend back to the Pliocene. Previous research at Bowers Ridge, south Bering Sea, has revealed stable levels of siliceous productivity over the onset of major Northern Hemisphere Glaciation (NHG) (c. 2.85-2.73 Ma). However, diatom silica isotope records of oxygen (δ18Odiatom) and silicon (δ30Sidiatom) presented here demonstrate that this interval was associated with a progressive increase in the supply of silicic acid to the region, superimposed on shift to a more dynamic environment characterized by colder temperatures and increased sea ice. This concluded at 2.58 Ma with a sharp increase in diatom productivity, further increases in photic zone nutrient availability and a permanent shift to colder sea surface conditions. These transitions are suggested to reflect a gradually more intense nutrient leakage from the subarctic northwest Pacific Ocean, with increases in productivity further aided by increased sea-ice and wind-driven mixing in the Bering Sea. In suggesting a linkage in biogeochemical cycling between the south Bering Sea and subarctic Northwest Pacific Ocean, mainly via the Kamchatka Strait, this work highlights the need to consider the interconnectivity of these two systems when future reconstructions are carried out in the region.

Item Type: Article
Date Type: Published Online
Status: Published
Schools: Earth and Ocean Sciences
Subjects: Q Science > QE Geology
Uncontrolled Keywords: Pliocene; diatom; isotope; nutrients; silica; silicon
Publisher: American Geophysical Union
ISSN: 0883-8305
Funders: Natural Environment Research Council
Date of First Compliant Deposit: 22 September 2016
Date of Acceptance: 29 August 2016
Last Modified: 04 Jun 2017 09:23
URI: http://orca.cf.ac.uk/id/eprint/94492

Citation Data

Cited 1 time in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item

Downloads

Downloads per month over past year

View more statistics