Climate variability in the North Pacific thermocline diagnosed from oxygen measurements: An update based on the U.S. CLIVAR/CO2 Repeat Hydrography cruises

Sabine Mecking, Chris Langdon, Richard A. Feely, Christopher L. Sabine, Curtis A. Deutsch, Dong Ha Min

Research output: Contribution to journalArticle

49 Citations (Scopus)

Abstract

New observations of oxygen variability in the North Pacific Ocean are reported on the basis of comparison of the U.S. Climate Variability and Predictability and Carbon (CLIVAR/CO2) Repeat Hydrography sections conducted along 30°N (2004) and 152°W (2006) with the earlier World Ocean Circulation Experiment (WOCE) data and other cruises along these sections. The largest changes in apparent oxygen utilization (AOU) continue to occur, as found in earlier North Pacific repeat section analyses, within the thermocline on σΘ = 26.6 kg m-3, which is the densest isopycnal to outcrop in the open North Pacific in climatological data. In the northeastern North Pacific along 152°W, where a total of five cruises (1980, 1984, 1991, 1997, and 2006) spanning a period of 26 years are available, the AOU changes correspond to an overall increase in AOU on σ Θ = 26.6 kg m-3 from the 1980s/early 1990s to 2006. However, from 1997 to 2006 a decrease in AOU is observed within the boundary region between the subtropical and subpolar gyres at 40°-45°N. Along the center axis of the subtropical gyre at 30°N, where two cruises are available (1994 and 2004), AOU has also substantially increased on σΘ = 26.6 kg m-3 from 1994 to 2004 in the eastern part of the section. The repeat section data along 152°W and 30°N are consistent with a pattern of decadal-scale ventilation anomalies that originate in the northwestern Pacific, possibly through variability (including cessation) of the σΘ = 26.6 kg m-3 outcrop, travel eastward along the subtropical-subpolar gyre boundary, and enter the northern portion of the subtropical gyre along the way. For the 152°W AOU data within the gyre boundary region (40°-45°N), good agreement exists with the close-by time series data from Ocean Station P (50°N, 145°W) where a bidecadal cycle in AOU has been observed. In contrast, a sensible correlation with the Pacific Decadal Oscillation could not be found.

Original languageEnglish
Article numberGB3015
JournalGlobal Biogeochemical Cycles
Volume22
Issue number3
DOIs
StatePublished - Sep 1 2008

Fingerprint

hydrography
thermocline
Temperature distribution
Oxygen
oxygen
climate
gyre
outcrop
Pacific Decadal Oscillation
Ventilation
ventilation
Time series
Carbon
time series
anomaly
carbon
ocean

ASJC Scopus subject areas

  • Global and Planetary Change
  • Atmospheric Science
  • Environmental Science(all)
  • Environmental Chemistry

Cite this

Climate variability in the North Pacific thermocline diagnosed from oxygen measurements : An update based on the U.S. CLIVAR/CO2 Repeat Hydrography cruises. / Mecking, Sabine; Langdon, Chris; Feely, Richard A.; Sabine, Christopher L.; Deutsch, Curtis A.; Min, Dong Ha.

In: Global Biogeochemical Cycles, Vol. 22, No. 3, GB3015, 01.09.2008.

Research output: Contribution to journalArticle

@article{22977a0270f14a7686abdbc2b271198b,
title = "Climate variability in the North Pacific thermocline diagnosed from oxygen measurements: An update based on the U.S. CLIVAR/CO2 Repeat Hydrography cruises",
abstract = "New observations of oxygen variability in the North Pacific Ocean are reported on the basis of comparison of the U.S. Climate Variability and Predictability and Carbon (CLIVAR/CO2) Repeat Hydrography sections conducted along 30°N (2004) and 152°W (2006) with the earlier World Ocean Circulation Experiment (WOCE) data and other cruises along these sections. The largest changes in apparent oxygen utilization (AOU) continue to occur, as found in earlier North Pacific repeat section analyses, within the thermocline on σΘ = 26.6 kg m-3, which is the densest isopycnal to outcrop in the open North Pacific in climatological data. In the northeastern North Pacific along 152°W, where a total of five cruises (1980, 1984, 1991, 1997, and 2006) spanning a period of 26 years are available, the AOU changes correspond to an overall increase in AOU on σ Θ = 26.6 kg m-3 from the 1980s/early 1990s to 2006. However, from 1997 to 2006 a decrease in AOU is observed within the boundary region between the subtropical and subpolar gyres at 40°-45°N. Along the center axis of the subtropical gyre at 30°N, where two cruises are available (1994 and 2004), AOU has also substantially increased on σΘ = 26.6 kg m-3 from 1994 to 2004 in the eastern part of the section. The repeat section data along 152°W and 30°N are consistent with a pattern of decadal-scale ventilation anomalies that originate in the northwestern Pacific, possibly through variability (including cessation) of the σΘ = 26.6 kg m-3 outcrop, travel eastward along the subtropical-subpolar gyre boundary, and enter the northern portion of the subtropical gyre along the way. For the 152°W AOU data within the gyre boundary region (40°-45°N), good agreement exists with the close-by time series data from Ocean Station P (50°N, 145°W) where a bidecadal cycle in AOU has been observed. In contrast, a sensible correlation with the Pacific Decadal Oscillation could not be found.",
author = "Sabine Mecking and Chris Langdon and Feely, {Richard A.} and Sabine, {Christopher L.} and Deutsch, {Curtis A.} and Min, {Dong Ha}",
year = "2008",
month = "9",
day = "1",
doi = "10.1029/2007GB003101",
language = "English",
volume = "22",
journal = "Global Biogeochemical Cycles",
issn = "0886-6236",
publisher = "American Geophysical Union",
number = "3",

}

TY - JOUR

T1 - Climate variability in the North Pacific thermocline diagnosed from oxygen measurements

T2 - An update based on the U.S. CLIVAR/CO2 Repeat Hydrography cruises

AU - Mecking, Sabine

AU - Langdon, Chris

AU - Feely, Richard A.

AU - Sabine, Christopher L.

AU - Deutsch, Curtis A.

AU - Min, Dong Ha

PY - 2008/9/1

Y1 - 2008/9/1

N2 - New observations of oxygen variability in the North Pacific Ocean are reported on the basis of comparison of the U.S. Climate Variability and Predictability and Carbon (CLIVAR/CO2) Repeat Hydrography sections conducted along 30°N (2004) and 152°W (2006) with the earlier World Ocean Circulation Experiment (WOCE) data and other cruises along these sections. The largest changes in apparent oxygen utilization (AOU) continue to occur, as found in earlier North Pacific repeat section analyses, within the thermocline on σΘ = 26.6 kg m-3, which is the densest isopycnal to outcrop in the open North Pacific in climatological data. In the northeastern North Pacific along 152°W, where a total of five cruises (1980, 1984, 1991, 1997, and 2006) spanning a period of 26 years are available, the AOU changes correspond to an overall increase in AOU on σ Θ = 26.6 kg m-3 from the 1980s/early 1990s to 2006. However, from 1997 to 2006 a decrease in AOU is observed within the boundary region between the subtropical and subpolar gyres at 40°-45°N. Along the center axis of the subtropical gyre at 30°N, where two cruises are available (1994 and 2004), AOU has also substantially increased on σΘ = 26.6 kg m-3 from 1994 to 2004 in the eastern part of the section. The repeat section data along 152°W and 30°N are consistent with a pattern of decadal-scale ventilation anomalies that originate in the northwestern Pacific, possibly through variability (including cessation) of the σΘ = 26.6 kg m-3 outcrop, travel eastward along the subtropical-subpolar gyre boundary, and enter the northern portion of the subtropical gyre along the way. For the 152°W AOU data within the gyre boundary region (40°-45°N), good agreement exists with the close-by time series data from Ocean Station P (50°N, 145°W) where a bidecadal cycle in AOU has been observed. In contrast, a sensible correlation with the Pacific Decadal Oscillation could not be found.

AB - New observations of oxygen variability in the North Pacific Ocean are reported on the basis of comparison of the U.S. Climate Variability and Predictability and Carbon (CLIVAR/CO2) Repeat Hydrography sections conducted along 30°N (2004) and 152°W (2006) with the earlier World Ocean Circulation Experiment (WOCE) data and other cruises along these sections. The largest changes in apparent oxygen utilization (AOU) continue to occur, as found in earlier North Pacific repeat section analyses, within the thermocline on σΘ = 26.6 kg m-3, which is the densest isopycnal to outcrop in the open North Pacific in climatological data. In the northeastern North Pacific along 152°W, where a total of five cruises (1980, 1984, 1991, 1997, and 2006) spanning a period of 26 years are available, the AOU changes correspond to an overall increase in AOU on σ Θ = 26.6 kg m-3 from the 1980s/early 1990s to 2006. However, from 1997 to 2006 a decrease in AOU is observed within the boundary region between the subtropical and subpolar gyres at 40°-45°N. Along the center axis of the subtropical gyre at 30°N, where two cruises are available (1994 and 2004), AOU has also substantially increased on σΘ = 26.6 kg m-3 from 1994 to 2004 in the eastern part of the section. The repeat section data along 152°W and 30°N are consistent with a pattern of decadal-scale ventilation anomalies that originate in the northwestern Pacific, possibly through variability (including cessation) of the σΘ = 26.6 kg m-3 outcrop, travel eastward along the subtropical-subpolar gyre boundary, and enter the northern portion of the subtropical gyre along the way. For the 152°W AOU data within the gyre boundary region (40°-45°N), good agreement exists with the close-by time series data from Ocean Station P (50°N, 145°W) where a bidecadal cycle in AOU has been observed. In contrast, a sensible correlation with the Pacific Decadal Oscillation could not be found.

UR - http://www.scopus.com/inward/record.url?scp=65549088820&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=65549088820&partnerID=8YFLogxK

U2 - 10.1029/2007GB003101

DO - 10.1029/2007GB003101

M3 - Article

AN - SCOPUS:65549088820

VL - 22

JO - Global Biogeochemical Cycles

JF - Global Biogeochemical Cycles

SN - 0886-6236

IS - 3

M1 - GB3015

ER -