過去1万1千年に比べて,ここ数十年における太陽の異常な活動
S K Solanki1, I G Usoskin, B Kromer
1Max-Planck-Institut für Sonnensystemforschung (formerly the Max-Planck-Institut für Aeronomie), 37191 Katlenburg-Lindau, Germany. solanki@mps.mpg.de
Nature
|October 29, 2004
まとめ
この研究では,放射性炭素データを用いて,1万1400年の太陽光斑数を再構築しました. 最近の太陽活動は非常に高く,8,000年以上前に見たレベルを超えています.
科学分野:
- * 太陽物理学と古気候学.
- * 長期の太陽活動とその潜在的な気候への影響を調査する.
背景:
- * 直接的な太陽光斑数観測は400年しか経っていない.
- *より長い太陽活動記録は,気候影響の研究と太陽ダイナモモデルにとって不可欠です.
研究 の 目的:
- * 過去1万1400年の太陽の斑点数を復元する.
- * 長期的な文脈で最近の太陽活動レベルを評価する.
- * 最近の気候変動に対する太陽の寄与を評価する.
主な方法:
- * デンドロクロノロジカルに日付付けられた放射性炭素濃度を用いて,過去の太陽光斑数の再構築.
- * 放射性炭素のレベルと太陽の斑点の活動とを関連付けるための物理ベースのモデルの適用.
主要な成果:
- *太陽の磁気活動のレベルは,過去70年間,11,400年の記録の中で例外的なものです.
- *同様の高い太陽活動期間の発生は稀で,約10%しか発生しなかった.
- * 過去のハイアクティビティエピソードのほとんどは,現在のエピソードより短い.
結論:
- *現在の高い太陽活動は,歴史的にまれで,20世紀の気候変動に寄与している可能性がある.
- *しかしながら,太陽の変動性は,過去30年にわたる激しい温暖化の主要な原動力である可能性は低い.
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