FN Archimer Export Format
PT J
TI The Deep Ocean's Carbon Exhaust
BT 
AF CHEN, Haidi
   HAUMANN, F. Alexander
   TALLEY, Lynne D.
   JOHNSON, Kenneth S.
   SARMIENTO, Jorge L.
AS 1:1;2:1;3:2;4:3;5:1;
FF 1:;2:;3:;4:;5:;
C1 1Atmospheric and Oceanic Sciences Program, Princeton University, Princeton, NJ, USA
   2Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California, USA
   3Monterey Bay Aquarium Research Institute, Moss Landing, CA, USA
C2 UNIV PRINCETON, USA
   UNIV CALIF SAN DIEGO, USA
   MONTEREY BAY AQUARIUM RES INST, USA
IF 5.2
TC 11
UR https://archimer.ifremer.fr/doc/00788/90005/95569.pdf
   https://archimer.ifremer.fr/doc/00788/90005/95570.docx
LA English
DT Article
CR OISO - OCÉAN INDIEN SERVICE D'OBSERVATION
DE ;carbon cycle;ocean circulation;Southern Ocean;biogeochemistry
AB The deep ocean releases large amounts of old, pre-industrial carbon dioxide (CO2) to the atmosphere through upwelling in the Southern Ocean, which counters the marine carbon uptake occurring elsewhere. This Southern Ocean CO2 release is relevant to the global climate because its changes could alter atmospheric CO2 levels on long time scales, and also affects the present-day potential of the Southern Ocean to take up anthropogenic CO2. Here, year-round profiling float measurements show that this CO2 release arises from a zonal band of upwelling waters between the Subantarctic Front and wintertime sea-ice edge. This band of high CO2 subsurface water coincides with the outcropping of the 27.8 kg m(-3) isoneutral density surface that characterizes Indo-Pacific Deep Water (IPDW). It has a potential partial pressure of CO2 exceeding current atmospheric CO2 levels ( increment PCO2) by 175 +/- 32 mu atm. Ship-based measurements reveal that IPDW exhibits a distinct increment PCO2 maximum in the ocean, which is set by remineralization of organic carbon and originates from the northern Pacific and Indian Ocean basins. Below this IPDW layer, the carbon content increases downwards, whereas increment PCO2 decreases. Most of this vertical increment PCO2 decline results from decreasing temperatures and increasing alkalinity due to an increased fraction of calcium carbonate dissolution. These two factors limit the CO2 outgassing from the high-carbon content deep waters on more southerly surface outcrops. Our results imply that the response of Southern Ocean CO2 fluxes to possible future changes in upwelling are sensitive to the subsurface carbon chemistry set by the vertical remineralization and dissolution profiles. 
PY 2022
PD JUN
SO Global Biogeochemical Cycles
SN 0886-6236
PU Amer Geophysical Union
VL 36
IS 7
UT 000828682400001
DI 10.1029/2021GB007156
ID 90005
ER

EF