TY - JOUR
T1 - Nutrient and dissolved inorganic carbon variability in the North Pacific
AU - Yasunaka, Sayaka
AU - Mitsudera, Humio
AU - Whitney, Frank
AU - Nakaoka, Shin ichiro
N1 - Funding Information:
We thank the many researchers and funding agencies responsible for the collection of data and quality control in SOCAT, GLODAP, WOD, and NIES/IOS SOO observations. We are grateful for the use of the CO2SYS program obtained from the Ocean Carbon Data System of NOAA National Centers for Environmental Information (https://www.nodc.noaa.gov/ocads/oceans/CO2SYS/co2rprt.html). This work was financially supported by JSPS KAKENHI Grant Number JP 18H04129 and 18H04909, and in part by the Global Environmental Research Coordination System, from the Ministry of the Environment, Japan (E1751). Comments from two anonymous reviewers, C. Yoshikawa, M. Shigemitsu, and T. Hashioka were useful.
Funding Information:
We thank the many researchers and funding agencies responsible for the collection of data and quality control in SOCAT, GLODAP, WOD, and NIES/IOS SOO observations. We are grateful for the use of the CO2SYS program obtained from the Ocean Carbon Data System of NOAA National Centers for Environmental Information ( https://www.nodc.noaa.gov/ocads/oceans/CO2SYS/co2rprt.html ). This work was financially supported by JSPS KAKENHI Grant Number JP 18H04129 and 18H04909, and in part by the Global Environmental Research Coordination System, from the Ministry of the Environment, Japan (E1751). Comments from two anonymous reviewers, C. Yoshikawa, M. Shigemitsu, and T. Hashioka were useful.
Publisher Copyright:
© 2020, The Author(s).
PY - 2021/2
Y1 - 2021/2
N2 - A compilation of surface water nutrient (phosphate, nitrate, and silicate) and partial pressure of CO2 (pCO2) observations from 1961 to 2016 reveals seasonal and interannual variability in the North Pacific. Nutrients and calculated dissolved inorganic carbon (DIC) reach maximum concentrations in March and minimum in August. Nutrient and DIC variability is in-phase (anti-phase) with changes in the mixed layer depth (sea surface temperature) north of 30 °N, and it is anti-phase (in-phase) with changes in Chl-a north of 40 °N (in 30 °N–40 °N). Seasonal drawdown of nutrients and DIC is larger toward the northwest and shows a local maximum in the boundary region between the subarctic and subtropics. Stoichiometric ratios of seasonal drawdown show that, compared to nitrate, silicate drawdown is large in the northwestern subarctic including the Bering and Okhotsk seas, and drawdown of carbon is larger toward the south. Net community production in mixed layer from March to July is estimated to be more than 6 gC/m2/mo in the boundary region between the subarctic and subtropics, the western subarctic, the Gulf of Alaska, and the Bering Sea. Nutrient and DIC concentrations vary with the Pacific Decadal Oscillation and the North Pacific Gyre Oscillation which cause changes in horizontal advection and vertical mixing. The DIC trend is positive in all analysis area and large in the western subtropics (> 1.0 μmol/l/yr). Averaged over the analysis area, it is increasing by 0.77 ± 0.03 μmol/l/yr (0.75 ± 0.02 μmol/kg/yr).
AB - A compilation of surface water nutrient (phosphate, nitrate, and silicate) and partial pressure of CO2 (pCO2) observations from 1961 to 2016 reveals seasonal and interannual variability in the North Pacific. Nutrients and calculated dissolved inorganic carbon (DIC) reach maximum concentrations in March and minimum in August. Nutrient and DIC variability is in-phase (anti-phase) with changes in the mixed layer depth (sea surface temperature) north of 30 °N, and it is anti-phase (in-phase) with changes in Chl-a north of 40 °N (in 30 °N–40 °N). Seasonal drawdown of nutrients and DIC is larger toward the northwest and shows a local maximum in the boundary region between the subarctic and subtropics. Stoichiometric ratios of seasonal drawdown show that, compared to nitrate, silicate drawdown is large in the northwestern subarctic including the Bering and Okhotsk seas, and drawdown of carbon is larger toward the south. Net community production in mixed layer from March to July is estimated to be more than 6 gC/m2/mo in the boundary region between the subarctic and subtropics, the western subarctic, the Gulf of Alaska, and the Bering Sea. Nutrient and DIC concentrations vary with the Pacific Decadal Oscillation and the North Pacific Gyre Oscillation which cause changes in horizontal advection and vertical mixing. The DIC trend is positive in all analysis area and large in the western subtropics (> 1.0 μmol/l/yr). Averaged over the analysis area, it is increasing by 0.77 ± 0.03 μmol/l/yr (0.75 ± 0.02 μmol/kg/yr).
KW - DIC
KW - NPGO
KW - Nitrate
KW - PDO
KW - Phosphate
KW - Silicate
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U2 - 10.1007/s10872-020-00561-7
DO - 10.1007/s10872-020-00561-7
M3 - Article
AN - SCOPUS:85090313565
VL - 77
SP - 3
EP - 16
JO - Journal of Oceanography
JF - Journal of Oceanography
SN - 0916-8370
IS - 1
ER -