地球上の二酸化炭素の総吸収量:地球規模分布と気候との共変量
Christian Beer1, Markus Reichstein, Enrico Tomelleri
1Biogeochemical Model-Data Integration Group, Max Planck Institute for Biogeochemistry, 07745 Jena, Germany. christian.beer@bgc-jena.mpg.de
Science (New York, N.Y.)
|July 7, 2010
まとめ
最大のCO2フローである陸上の総一次生産 (GPP) は,観測データを用いて年間123PgCと推定された. この研究は,GPPを強調しています.
科学分野:
- 地球システム科学 地球システム科学
- エコロジー エコロジー エコロジー
- バイオジオケミストリー バイオジオケミストリー
背景:
- 陸上の原産総量 (GPP) は,世界最大の二酸化炭素 (CO2) 流量であり,生態系機能に根本的な影響を与えている.
- GPPの正確な定量化は,世界の炭素循環とその気候との相互作用を理解するために不可欠です.
- 既存のバイオスフィアモデルは,GPPパターンをシミュレートする上で大きな不一致を示しており,モデルのコンポーネントを改善する必要があることを示しています.
研究 の 目的:
- 地球上の地上のGPPの観測に基づく推定を提供すること.
- GPPと気候要因,特に降雨量との関係を調査する.
- 気候変動の予測のための現在のバイオスフィアモデルの限界を特定する.
主な方法:
- 世界各地の多数のサイトから,エディの共変量流量データを利用した.
- 流量データを処理および分析するために,さまざまな診断モデルを使用しました.
- 空間的に分布したGPPを推定し,気候変数との共変性を分析した.
主要な成果:
- 観測に基づくGPPの推定値は,年間123±8ペタグラムの炭素 (PgC年−1) であった.
- 熱帯雨林とサバンナが大幅に貢献し,総GDPの60%を占めています.
- 植生地の約40%は,GPPが降雨パターンに強く影響されていることを示しています.
結論:
- 現在の生物圏モデルは,プロセスやフィードバックメカニズムが欠けているため,気候に対する植物の反応を完全に捉えることができない可能性があります.
- 導出されたGPP推定値とその気候共変数は,結合された気候-炭素サイクルモデルを精錬するために貴重なデータを提供します.
- 改善されたモデルは,より正確な気候変動予測と生態系の動態を理解するために不可欠です.
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