FN Archimer Export Format
PT J
TI Upper ocean O-2 trends: 1958-2015
BT 
AF ITO, Takamitsu
   MINOBE, Shoshiro
   LONG, Matthew C.
   DEUTSCH, Curtis
AS 1:1;2:2,3;3:4;4:5;
FF 1:;2:;3:;4:;
C1 1School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
   2Department of Natural History Sciences, Graduate School of Science, Hokkaido University, Sapporo, Japan
   of Earth and Planetary Sciences, Faculty of Science, Hokkaido University, Sapporo, Japan
   4Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, Colorado, USA
   of Oceanography, University of Washington, Seattle, Washington, USA
C2 GEORGIA INST TECHNOL, USA
   UNIV HOKKAIDO, JAPAN
   UNIV HOKKAIDO, JAPAN
   NCAR NATL CTR ATMOSPHER RES, USA
   UNIV WASHINGTON, USA
IF 4.339
TC 110
UR https://archimer.ifremer.fr/doc/00801/91320/97122.pdf
   https://archimer.ifremer.fr/doc/00801/91320/97123.pdf
   https://archimer.ifremer.fr/doc/00801/91320/97124.pdf
   https://archimer.ifremer.fr/doc/00801/91320/97125.pdf
   https://archimer.ifremer.fr/doc/00801/91320/97126.pdf
   https://archimer.ifremer.fr/doc/00801/91320/97127.pdf
LA English
DT Article
CR OISO - OCÉAN INDIEN SERVICE D'OBSERVATION
DE ;climate change;biogeochemical cycling;marine chemistry;global warming;data analysis;climate impacts
AB Historic observations of dissolved oxygen (O-2) in the ocean are analyzed to quantify multidecadal trends and variability from 1958 to 2015. Additional quality control is applied, and the resultant oxygen anomaly field is used to quantify upper ocean O-2 trends at global and hemispheric scales. A widespread negative O-2 trend is beginning to emerge from the envelope of interannual variability. Ocean reanalysis data are used to evaluate relationships with changes in ocean heat content (OHC) and oxygen solubility (O-2,O-sat). Global O-2 decline is evident after the 1980s, accompanied by an increase in global OHC. The global upper ocean O-2 inventory (0-1000m) changed at the rate of -243124TmolO(2) per decade. Further, the O-2 inventory is negatively correlated with the OHC (r=-0.86; 0-1000m) and the regression coefficient of O-2 to OHC is approximately -8.20.66nmolO(2)J(-1), on the same order of magnitude as the simulated O-2-heat relationship typically found in ocean climate models. Variability and trends in the observed upper ocean O-2 concentration are dominated by the apparent oxygen utilization component with relatively small contributions from O-2,O-sat. This indicates that changing ocean circulation, mixing, and/or biochemical processes, rather than the direct thermally induced solubility effects, are the primary drivers for the observed O-2 changes. The spatial patterns of the multidecadal trend include regions of enhanced ocean deoxygenation including the subpolar North Pacific, eastern boundary upwelling systems, and tropical oxygen minimum zones. Further studies are warranted to understand and attribute the global O-2 trends and their regional expressions. Plain Language Summary This new paper describes the analysis of the dissolved oxygen in the global ocean using the most recent version of the World Ocean Database for the period of 1955 to 2015. After careful examination of the data, we found that a statistically significant, widespread O-2 decline is emerging beyond the envelope of natural fluctuations. Our study also reveals a tight relationship between O-2 inventories and the ocean heat content. The spatial pattern and magnitude of this relationship are consistent with expectations derived from mechanistic ocean climate models forced under climate warming scenarios. Taken together, the trends we document here are suggestive of the effects of the ocean warming beginning to supersede natural variability and emerge as a recognizable signal. This merits additional scrutiny over the coming years. 
PY 2017
PD MAY
SO Geophysical Research Letters
SN 0094-8276
PU Amer Geophysical Union
VL 44
IS 9
UT 000402143700030
BP 4214
EP 4223
DI 10.1002/2017GL073613
ID 91320
ER

EF