人為的なCO2が海洋のCaCO3システムに与える影響
Richard A Feely1, Christopher L Sabine, Kitack Lee
1Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, Seattle, WA 98115-6349, USA. richard.a.feely@noaa.gov
まとめ
二酸化炭素 (CO2) の上昇による海洋酸化は,炭酸カルシウム (CaCO3) の溶解を増加させます. 世界の海洋のCaCO3溶解率は,年間0.5ペタグラムのCaCO3-Cであると推定され,貝殻を形成する種に影響を与えています.
科学分野:
- 海洋学 海洋学とは
- マリン・ケミストリー (海洋化学)
- 気候科学 気候科学
背景:
- 2世紀にわたって大気中の二酸化炭素 (CO2) の濃度が上昇したことで,海洋のCO2吸収が増加しました.
- このプロセスは,海洋酸性化につながり,カルシウム炭酸 (CaCO3) 粒子の飽和状態が変化しました.
研究 の 目的:
- 世界の海におけるCaCO3溶解速度を in situで推定する.
- 人為的なCO2がCaCO3の殻を形成する種に及ぼす将来の影響について議論する.
主な方法:
- CaCO3の溶解率を推定するために,総アルカリ性およびクロロフッ素炭素 (CFC) のデータを利用しました.
- 1kg/年あたりマイクロモルの溶解率を決定するためにデータを分析した.
主要な成果:
- CaCO3の溶解速度は,年間1kgあたり0.003~1.2マイクロモールであった.
- 溶解はアラゴナイトの飽和地平線近くから始まります.
- 世界の海洋のCaCO3溶解率は,年間約0.5 +/- 0.2ペタグラムのCaCO3-Cであると推定されています.
結論:
- 推定の世界的なCaCO3溶解率は,CaCO3.3の総輸出生産量の45~65%を占めている.
- 海洋酸性化は,海洋生態系,特に貝殻を形成する生物に重大な脅威をもたらしています.
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