将来の気候のシミュレーションにおける地表の変化の重要性
Johannes J Feddema1, Keith W Oleson, Gordon B Bonan
1Department of Geography, University of Kansas, Lawrence, KS 66045, USA. feddema@ku.edu
Science (New York, N.Y.)
|December 13, 2005
まとめ
土地の覆いの変化は2100年までに地域の気候を大幅に変化させ,気温と大気循環に影響を与えます. A2シナリオは,B1よりも顕著な効果を示しており,農業の拡大が異なる地域における温暖化と冷却を引き起こしている.
科学分野:
- 気候科学 気候科学
- 環境科学 環境科学
- 地球システム科学 地球システム科学
背景:
- 気候変動に関する政府間パネル (IPCC) の排出シナリオに関する特別報告書 (SRES) は,一時的な気候シミュレーション (A2とB1) を提供しています.
- 以前の気候モデリングは,大気圧力のみに焦点を当てており,地表の変化の影響を潜在的に過小評価していました.
研究 の 目的:
- SRESの気候シミュレーションに地表の変化を組み込むことの影響を調査する.
- 土地の覆面の変化を含めると,A2シナリオとB1シナリオの地域気候結果を比較する.
主な方法:
- SRES A2およびB1シナリオに基づく一時的な気候シミュレーションを使用しました.
- 現存する気候モデルに地表の変化の影響を統合した.
- 地域的な気候の差異を分析したシミュレーションの間で,土地の覆面の変化と,その変化のないシミュレーション.
主要な成果:
- 2100年までに,地表の変化は,大気力のみと比較して,地域の気候を大幅に変化させる.
- A2シナリオにおける農業の拡大は,アマゾンの大幅な温暖化と,上層大気と海洋の冷却を引き起こす.
- 中緯度の農業の拡大は,冷却と日々の気温の範囲の減少につながり,A2の効果はより顕著で,B1とはしばしば反対です.
結論:
- 土地の覆面の変化は地域気候の重要な要因であり,将来の気候予測にそれらを含めることが必要である.
- A2の排出シナリオは,地表の変化と併せて,B1のシナリオよりも地域的な気候の変化がより劇的であることを示しています.
- ハドリー・システムやモンスーン・システムなどの大気循環への影響は,熱帯外の気候変化に影響を与えます.
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