ホロセーン - プレイストセーン後期気候 青海・チベット高原の氷芯記録
まとめ
中国のダンデ氷河からの気候記録は,後期氷河期がより冷たく湿った状態であったことを示しています. 最近の数十年は,ホロセンの最大値に匹敵する最も暖かい年代の一つです.
科学分野:
- 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
- 氷河学 氷河学とは
- 気候科学 気候科学
背景:
- 氷の芯は,過去の気候条件の貴重なアーカイブを提供します.
- 青海・チベット高原は,アジアの気候動態を理解する上で重要な地域である.
研究 の 目的:
- ホロセーンと後期氷河期 (LGS) における亜熱帯気候変化を再構築する.
- LGSの気候条件とホロセーン時代の気候条件を比較する.
主な方法:
- ダンデの氷冠の岩盤に掘削された3つの深い氷芯の分析.
- 同位体組成 (デルタ(18) O),塵含量,溶性エアロゾール,氷結晶のサイズについて調べます.
主要な成果:
- 氷河期末期の条件は,ホロセーンと比較して,より低温,降水量の増加,およびより高い塵量で特徴付けられました.
- デルタ18O比,塵濃度,溶性エアロゾール,氷結晶の大きさの大きな変化が,LGSからホロセーンへの移行を象徴しています.
- これらの急速な気候変動は,約1万年前に起こった.
- 過去60年間は,全氷河核記録の中で最も暖かい時期の1つであり,ホロセーン熱の最大値と比較できます.
結論:
- ダンデの氷帽の氷芯は,過去数十万年にわたる亜熱帯気候の変動の詳細なプロキシを提供します.
- 急速な気候変動は,最後の氷河期の終わりに発生し,地域の気候に影響を与えました.
- 最近の温暖化傾向は,現在の気候システムにおける重大な変化を強調しています.
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