気候システムへの半乾燥森林の貢献
1Environmental Sciences and Energy Research, Weizmann Institute of Science, Rehovot 76100, Israel.
まとめ
森林は炭素を吸収し,冷却効果をもたらしますが,これは温暖化放射線によって相殺されます. 砂漠化は地球表面温度にも影響を及ぼし,温暖化傾向を緩和します.
科学分野:
- 気候科学 気候科学
- 森林生態学 森林生態学 森林生態学
- 地球システム科学 地球システム科学
背景:
- 森林は,炭素の吸収と太陽放射線の吸収を通じて,地球温暖化に影響を与えます.
- 対照的な放射線効果 (冷却対温暖化) は,気候に対する森林の影響を複雑にします.
研究 の 目的:
- 乾燥林界地帯の森林の気候への影響を調査する.
- これらの生態系における炭素収束と放射性強制のバランスを定量化する.
主な方法:
- 乾燥した森林地帯 (降雨量200~600mm) での9年間の研究.
- 炭素結合率と放射線効果 (短波アルベドと長波放射線) の分析.
主要な成果:
- 光合成活動の早春へのシフトにより,かなりの炭素結合が発生します.
- この冷却効果は,長波放射線抑制による温暖化効果によって相殺されます.
- 短波と長波の放射線効果の組み合わせは,アルベドの影響を2倍にし,バランスをとるために数十年にわたる炭素蓄積を必要とします.
結論:
- 乾燥過渡地帯の森林は,複雑な気候フィードバックループを示します.
- 砂漠化は,温暖化傾向を緩和し,重大な負の強制効果を及ぼしています.
- 森林による温暖化効果を相殺するために,長期的な炭素蓄積は極めて重要です.
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