気候による大気中のCO2の変動により,亜熱帯の北太平洋でCO2が沈んでいく
John E Dore1, Roger Lukas, Daniel W Sadler
1Department of Oceanography, School of Ocean and Earth Science and Technology, University of Hawaii, 1000 Pope Road, Honolulu, Hawaii 96822, USA. jdore@hawaii.edu
Nature
|August 15, 2003
まとめ
海の二酸化炭素の吸収は1989年から2001年にかけてハワイ近くの海域で著しく減少した. 過剰な蒸発により,海面の二酸化炭素が増加し,海面の二酸化炭素が減少した.
科学分野:
- 海洋学 海洋学 海洋学
- 気候科学 気候科学
- バイオジオケミストリー バイオジオケミストリー
背景:
- 海洋は大気中の二酸化炭素を吸収する主要なシンクとして機能する.
- この炭素吸収槽の強さは,物理的および生物学的要因の変化により,年間時間スケールによって変化します.
- これらの要因は,二酸化炭素が地表混合層に流入し,地表混合層から流出することを制御する.
研究 の 目的:
- 海洋の二酸化炭素測定の13年間のタイムシリーズを分析するために.
- 亜熱帯北太平洋のステーションALOHAの二酸化炭素シンク強度の変化を調査する.
- 海洋の炭素吸収の観測された変動に寄与する要因を特定する.
主な方法:
- 海洋の二酸化炭素測定の13年間のタイムシリーズ (1989-2001) の分析.
- サブトロピカル北太平洋の重要な監視拠点であるALOHAステーションのデータを活用して.
- 表面海洋の二酸化炭素部分圧力と蒸発などの物理的パラメータとの関係を調査する.
主要な成果:
- 1989年から2001年にかけて,海洋の二酸化炭素シンクの強さの有意な減少が観察されました.
- 海洋表面における二酸化炭素の部分圧の上昇は,シンク強度の低下の主な要因として特定されました.
- 水質における過剰な蒸発と溶質の濃度が,地表海洋の二酸化炭素レベルに影響を与える重要な要因であることが判明しました.
結論:
- 海洋の二酸化炭素吸収は,地域の降雨と蒸発パターンによって大きく影響を受けます.
- 気候変動の変動,特に蒸発の変化は,大気中の二酸化炭素を吸収する海洋の能力を大幅に変化させる可能性があります.
- これらの発見は,気候に起因する水文学的変化に対する海洋の炭素吸収体の感受性を強調しています.
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