日本地球惑星科学連合2019年大会

講演情報

[J] ポスター発表

セッション記号 A (大気水圏科学) » A-OS 海洋科学・海洋環境

[A-OS16] 海洋化学・生物学

2019年5月27日(月) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 8ホール)

コンビーナ:山田 奈海葉(国立研究開発法人 産業技術総合研究所)、安中 さやか(国立研究開発法人 海洋研究開発機構)、齊藤 宏明(東京大学大気海洋研究所)

[AOS16-P02] 1991年から2017年間で太平洋に蓄積した人為起源CO2

*村田 昌彦1Carter B.R.2,3Feely R.A.3Wanninkhof R.3纐纈 慎也1Sonnerup R.E.2Pardo P.C.4Sabine C.L.5Johnson G. C.3Sloyan B.M.6Mecking S.2Tilbrook B.6Speer K.7Talley L.D.8Millero F.J.9Wijffels S.E.6,10Macdonald A.M.10Gruber N.11Bullister J. L.3 (1.国立研究開発法人海洋研究開発機構、2.University of Washington、3.NOAA、4.University of Tasmania、5.University of Hawaii Manoa、6.CSIRO、7.The Florida State University、8.University of California、9.University of Miami、10.Woods Hole Oceanographic Institution、11.IBP)

The ocean is storing between a fourth and a third of anthropogenic CO2 (Canth) emissions. Monitoring the oceanic CO2 sink is critical to assessing the global carbon budget. We estimate total Canth storage and accumulation rates from 14 Pacific hydrographic sections that have been occupied two to four times over the past decades, with most sections having been recently measured as part of the Global Ocean Hydrographic Investigations Program (GO-SHIP). The Canth sink over the top 1500 m of the Pacific increased from 8.6 (±1.1, 1σ) Pg of carbon decade-1 from 1995 to 2005 to 10.8 (±1.1) PgC decade-1 from 2005 to 2015. We estimate 1.2 of this observed 2.2 PgC decade-1 increase in the rate of accumulation between decades is attributable to atmospheric anthropogenic CO2 increases alone, while the remaining increase is consistent with recent literature suggesting there was an increase in the ocean carbon sink during the mid-2000s. Methods that allow for analysis of multiple occupations of sections and comparisons between different sections spaced irregularly in time are introduced. The accuracy of the resulting Canth accumulation reconstructions is limited by the accuracy of the data, suggesting that a continuation of repeat hydrographic surveys with a high emphasis on obtaining multiple independent realizations of the most accurate possible measurements is a critical piece of future carbon cycle monitoring.