Impact of end-member mixing on depth distributions of δ<sup>13</sup>C, cadmium and nutrients in the N. Atlantic Ocean

Paul Quay, Jingfeng Wu

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

The PO<inf>4</inf>, δ<sup>13</sup>C and Cd depth distributions measured in the N. Atlantic Ocean during recent GEOTRACES and CLIVAR cruises are a result of biological and circulation processes, with in-situ uptake and remineralization of organic matter dominating in the upper ~300m and mixing of water masses dominating in the thermocline and deep sea. The observed slopes of the NO<inf>3</inf>-PO<inf>4</inf>, preindustrial δ<sup>13</sup>C-PO<inf>4</inf> and (by analogy) Cd-PO<inf>4</inf> along isopycnals deviate significantly from that expected from Redfield in the thermocline and deep sea and in each case the observed slope is similar to the slopes of the end-member water masses being mixed. The depth increase in the Cd-PO<inf>4</inf> slope resulting from end-member mixing explains the observed kink at ~1μM PO<inf>4</inf> in the Cd-PO<inf>4</inf> relationship in the N. Atlantic. The observation that the PO<inf>4</inf>- preindustrial δ<sup>13</sup>C-Cd relationship in the modern N. Atlantic is heavily influenced by end-member mixing throughout most of the water column complicates the use of δ<sup>13</sup>C and Cd as proxies of the paleocean's nutrient distribution because changes in the PO<inf>4</inf>-δ<sup>13</sup>C-Cd composition of locally and remotely produced end-members water masses would change the PO<inf>4</inf>, δ<sup>13</sup>C and Cd depth distributions in the paleo N. Atlantic Ocean.

Original languageEnglish (US)
Pages (from-to)107-116
Number of pages10
JournalDeep-Sea Research Part II: Topical Studies in Oceanography
Volume116
DOIs
StatePublished - Jun 1 2015

Fingerprint

vertical distribution
cadmium
water mass
nutrient
ocean
thermocline
deep sea
remineralization
water column
organic matter

Keywords

  • Cadmium
  • End-member mixing
  • N. Atlantic Ocean
  • Phosphate
  • δ<sup>13</sup>C

ASJC Scopus subject areas

  • Oceanography

Cite this

@article{8dd821a9985e4f2a8697c3890daf9ab4,
title = "Impact of end-member mixing on depth distributions of δ13C, cadmium and nutrients in the N. Atlantic Ocean",
abstract = "The PO4, δ13C and Cd depth distributions measured in the N. Atlantic Ocean during recent GEOTRACES and CLIVAR cruises are a result of biological and circulation processes, with in-situ uptake and remineralization of organic matter dominating in the upper ~300m and mixing of water masses dominating in the thermocline and deep sea. The observed slopes of the NO3-PO4, preindustrial δ13C-PO4 and (by analogy) Cd-PO4 along isopycnals deviate significantly from that expected from Redfield in the thermocline and deep sea and in each case the observed slope is similar to the slopes of the end-member water masses being mixed. The depth increase in the Cd-PO4 slope resulting from end-member mixing explains the observed kink at ~1μM PO4 in the Cd-PO4 relationship in the N. Atlantic. The observation that the PO4- preindustrial δ13C-Cd relationship in the modern N. Atlantic is heavily influenced by end-member mixing throughout most of the water column complicates the use of δ13C and Cd as proxies of the paleocean's nutrient distribution because changes in the PO4-δ13C-Cd composition of locally and remotely produced end-members water masses would change the PO4, δ13C and Cd depth distributions in the paleo N. Atlantic Ocean.",
keywords = "Cadmium, End-member mixing, N. Atlantic Ocean, Phosphate, δ<sup>13</sup>C",
author = "Paul Quay and Jingfeng Wu",
year = "2015",
month = "6",
day = "1",
doi = "10.1016/j.dsr2.2014.11.009",
language = "English (US)",
volume = "116",
pages = "107--116",
journal = "Deep-Sea Research Part II: Topical Studies in Oceanography",
issn = "0967-0645",
publisher = "Elsevier Limited",

}

TY - JOUR

T1 - Impact of end-member mixing on depth distributions of δ13C, cadmium and nutrients in the N. Atlantic Ocean

AU - Quay, Paul

AU - Wu, Jingfeng

PY - 2015/6/1

Y1 - 2015/6/1

N2 - The PO4, δ13C and Cd depth distributions measured in the N. Atlantic Ocean during recent GEOTRACES and CLIVAR cruises are a result of biological and circulation processes, with in-situ uptake and remineralization of organic matter dominating in the upper ~300m and mixing of water masses dominating in the thermocline and deep sea. The observed slopes of the NO3-PO4, preindustrial δ13C-PO4 and (by analogy) Cd-PO4 along isopycnals deviate significantly from that expected from Redfield in the thermocline and deep sea and in each case the observed slope is similar to the slopes of the end-member water masses being mixed. The depth increase in the Cd-PO4 slope resulting from end-member mixing explains the observed kink at ~1μM PO4 in the Cd-PO4 relationship in the N. Atlantic. The observation that the PO4- preindustrial δ13C-Cd relationship in the modern N. Atlantic is heavily influenced by end-member mixing throughout most of the water column complicates the use of δ13C and Cd as proxies of the paleocean's nutrient distribution because changes in the PO4-δ13C-Cd composition of locally and remotely produced end-members water masses would change the PO4, δ13C and Cd depth distributions in the paleo N. Atlantic Ocean.

AB - The PO4, δ13C and Cd depth distributions measured in the N. Atlantic Ocean during recent GEOTRACES and CLIVAR cruises are a result of biological and circulation processes, with in-situ uptake and remineralization of organic matter dominating in the upper ~300m and mixing of water masses dominating in the thermocline and deep sea. The observed slopes of the NO3-PO4, preindustrial δ13C-PO4 and (by analogy) Cd-PO4 along isopycnals deviate significantly from that expected from Redfield in the thermocline and deep sea and in each case the observed slope is similar to the slopes of the end-member water masses being mixed. The depth increase in the Cd-PO4 slope resulting from end-member mixing explains the observed kink at ~1μM PO4 in the Cd-PO4 relationship in the N. Atlantic. The observation that the PO4- preindustrial δ13C-Cd relationship in the modern N. Atlantic is heavily influenced by end-member mixing throughout most of the water column complicates the use of δ13C and Cd as proxies of the paleocean's nutrient distribution because changes in the PO4-δ13C-Cd composition of locally and remotely produced end-members water masses would change the PO4, δ13C and Cd depth distributions in the paleo N. Atlantic Ocean.

KW - Cadmium

KW - End-member mixing

KW - N. Atlantic Ocean

KW - Phosphate

KW - δ<sup>13</sup>C

UR - http://www.scopus.com/inward/record.url?scp=84929948696&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84929948696&partnerID=8YFLogxK

U2 - 10.1016/j.dsr2.2014.11.009

DO - 10.1016/j.dsr2.2014.11.009

M3 - Article

AN - SCOPUS:84929948696

VL - 116

SP - 107

EP - 116

JO - Deep-Sea Research Part II: Topical Studies in Oceanography

JF - Deep-Sea Research Part II: Topical Studies in Oceanography

SN - 0967-0645

ER -