1980年以来,陸と海の二酸化炭素流動における地域的な変化
P Bousquet1, P Peylin, P Ciais
1Laboratoire des Sciences du Climat et de l'Environnement (LSCE), F-91198 Gif-sur-Yvette Cedex, France. pbousquet@cea.fr
まとめ
世界的な炭素バランスの変動は,陸上の流れが海洋の流れの2倍の変動性を示しています. 熱帯地域は1980年代の炭素変化を主導し,北部の土地は1990年代に主導した.
科学分野:
- 地球システム科学 地球システム科学
- 大気化学 大気化学
- エコロジー エコロジー エコロジー
背景:
- 大気中の二酸化炭素 (CO2) は重要な温室効果ガスである.
- 地域の炭素バランスを理解することは,気候変動の緩和に不可欠です.
- 長期的なCO2測定は,炭素循環の研究に貴重なデータを提供します.
研究 の 目的:
- 大気中のCO2測定を用いて,海洋と大陸の地域的な炭素バランスの年次変化を推論する.
- 陸上と海洋の炭素フローの変動性を定量化するために.
- 年間間炭素バランスの変動に支配的な貢献者の変化を時間とともに特定する.
主な方法:
- 20年間の大気中のCO2測定 (1980-1998) に逆モデルを適用した.
- 海と陸の生態系からの地域的な炭素流れの分析.
- 陸地と海洋の沈殿槽の間の炭素流動の変動の比較.
主要な成果:
- 地球上の陸上の炭素流は,1980年から1998年の間に海洋流のおよそ2倍に変動していた.
- 熱帯地の生態系は,1980年代における年間間炭素バランスの変化の主な原動力であった.
- 北部中高緯度の陸地生態系が1990年から1995年にかけての炭素バランスの変化の主な要因となった.
- 北米では,1992年から1993年にかけて,1989年から1990年に比べて,炭素吸収が著しく増加することが観察されました.
結論:
- 陸上の生態系は,海洋と比較して,炭素フローの年間間変動が高くなります.
- 世界的な炭素バランスの変化の主な原動力は,過去20年間で地理的にシフトしています.
- 北米における炭素吸収の拡大など,地域分析は,炭素循環のダイナミックな性質を強調している.
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