Recent deceleration of oceanic pCO2 increase in the western North Pacific in winter

• Midorikawa, Takashi

• Ishii, Masao

• Kosugi, Naohiro

• Sasano, Daisuke

• Nakano, Toshiya

• Saito, Shu

• Sakamoto, Naoaki

• Nakano, Hideyuki

• Inoue, Hisayuki Y.

Abstract

Recent changes in oceanic CO2 partial pressure (pCO2^[sea]) have attracted increasing interest as they relate to the increase in atmospheric CO2 and climate change. We report decadal changes in the growth rates of pCO2^[sea] in latitudinal zones from 3°N to 33°N along the repeat hydrographic line at 137°E in the western North Pacific in winter. The growth rates of pCO2^[sea] for 1999-2009 (-0.3 ± 0.9 [mean ± 1σ] to 1.7 ± 0.5 μatm yr^[-1]) were lower than those for 1984-1997 (0.7 ± 0.3 to 2.2 ± 0.6 μatm yr^[-1]) at most latitudes, indicative of the recent notable deceleration of pCO2^[sea] increase. For latitudes around 10-20°N, we attribute the reduction in the growth rate of pCO2^[sea] for 1999-2009 primarily to the reduction in the contribution from dissolved inorganic carbon (DIC) originating from a reduction in carbon accumulation associated with the expansion of the western Subtropical Gyre towards the south.

Journal

• Geophysical Research Letters

  Geophysical Research Letters 39 L12601-, 2012-06-19

  American Geophysical Union

Details

• CRID: 1050282813987537408
• NII Article ID: 120005039169
• HANDLE: 2115/50929
• ISSN: 00948276
• Text Lang: en
• Article Type: journal article
• Data Source:
  • IRDB
  • CiNii Articles