北大西洋のカーボンシンクの年間変動
Nicolas Gruber1, Charles D Keeling, Nicholas R Bates
1Institute of Geophysics and Planetary Physics and Department of Atmospheric Sciences, University of California, Los Angeles, CA 90095, USA. ngruber@igpp.ucla.edu
まとめ
北大西洋 北大西洋 北大西洋
科学分野:
- 海洋学 海洋学とは
- 気候科学 気候科学
- 炭素循環に関する研究
背景:
- 北大西洋は大気中の二酸化炭素の重要な海水槽である.
- このカーボンシンクの時間的な変動性は十分に理解されていません.
- 炭素吸収場を理解することは,気候変動の緩和に不可欠です.
研究 の 目的:
- 北大西洋の海洋炭水化物の時間的変動を調査するために.
- 上部海洋における炭素変動の主要な要因を特定する.
- 観測された変動の盆地全体の潜在的な影響を評価する.
主な方法:
- 海洋上部における無機炭素観測の18年間のタイムシリーズの分析.
- 北西亜熱帯北大西洋のバミューダの近くのデータを活用して.
- 冬の混合層の深さや海面温度異常と炭素の変動を相関させる.
主要な成果:
- 北大西洋のカーボンシンクで,年ごとに大きな変動が観察されました.
- 主要な要因として,冬の混合層の深さと海面温度異常を特定した.
- 変動は北大西洋振動 (NAO) と関連した盆地全体のパターンを表しています.
結論:
- 北大西洋の炭素シンクの強さは,時間的な変動が顕著である.
- 北大西洋振動 (NAO) は,盆地全体でこの変動を調整している可能性が高い.
- 炭素シンク強度の推定変動は,年間約+/-0.3ペタグラムの炭素,ほぼ+/-50%です.
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