気候:今日の太陽活動がどれほど異常なのか?
Raimund Muscheler1, Fortunat Joos, Simon A Müller
1National Center for Atmospheric Research, Climate and Global Dynamics Division, Paleoclimatology, Boulder, Colorado 80305-3000, USA. raimund@ucar.edu
Nature
|July 29, 2005
まとめ
ここ数十年の太陽活動量は,過去8000年に比べて,特に高くないかもしれません. 放射性炭素記録の拡張分析は,以前の世紀における太陽風の磁場強さと同等またはより高いことを示しています.
科学分野:
- 気候科学 気候科学
- 太陽物理 太陽物理学
- 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
背景:
- 地球温暖化を理解するには,過去の太陽活動と,気候変動における太陽の役割の文脈が必要です.
- 以前の研究では,最近の太陽活動が過去8000年にわたって例外的に高かったことが示唆されていました.
研究 の 目的:
- 長期にわたる太陽風の磁場強さを分析することによって,最近の太陽活動の例外性を再評価する.
- 現在の太陽活動とその気候への潜在的な影響について,より正確な歴史的文脈を提供するためです.
主な方法:
- 放射性炭素記録の拡張分析.
- 過去数世紀にわたって太陽風の磁場強度の再構築.
主要な成果:
- 過去数世紀に太陽風の磁場強度が最近のレベルと同等またはそれ以上であったいくつかの期間を特定しました.
- 最近の太陽活動が過去8000年間で前例のないものであるという考えに異議を唱えた.
結論:
- 最近の太陽活動レベルは,以前に提案されたほど例外的に高いものではないかもしれません.
- 太陽の磁場強さは,過去には,今日のような,あるいはそれよりも高い周期で,変動を示している.
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