過去1000年の気候変動の原因
1Department of Oceanography, Texas A&M University, College Station, TX 77843, USA.
まとめ
地球温暖化は加速しており,20世紀の気温は前例のない上昇を示しています. 太陽光照射や火山活動などの自然要因は,過去の温暖化の一部を説明しますが,温室効果ガスの強制は現在支配的です.
科学分野:
- 気候科学 気候科学
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- 気候モデリング
背景:
- 1000年の北半球温度再構築は,20世紀の温暖化に関する歴史的文脈を提供します.
- 過去の気候変動の変動を理解することは,自然的な気候変動と人為的な影響を区別するために不可欠です.
研究 の 目的:
- 20世紀の温暖化を1000年の歴史的文脈に置くために.
- 再構築と気候モデルを使用して,さまざまな気候変動メカニズムをテストする.
- 最近の温暖化における,温室効果ガスの強制と自然的な強制の役割を評価する.
主な方法:
- 観測データとエネルギーバランス気候モデルのシミュレーションの比較.
- 再構築された温度タイムシリーズと気候モデルの制御走行の分析.
- 温室効果ガスの分離は,過去千年における気温動向に強い影響を及ぼしている.
主要な成果:
- 1850年以前の10年間の気温変動の41~64%は,太陽光照射と火山活動に起因している.
- 気候モデルの残留値は,再構築された温度残留値と一致し,低周波変動のモデル推定値を検証します.
- 温室効果ガス強制のみを考慮する20世紀後半の温暖化は,モデル予測と密接に一致しています.
結論:
- 温室効果ガスの影響は,20世紀後半のユニークな温暖化によって証明された,自然の変動レベルを超えました.
- 予測される21世紀の地球温暖化は,過去の自然変動と最後の氷期間の温度を大幅に上回る.
- 証拠は,温室効果ガスの強制を,最近のおよび将来の気候変動の主な原動力として支持しています.
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