晴れた空の可視性は,1973年から2007年まで,地球上の陸上では減少しています
Kaicun Wang1, Robert E Dickinson, Shunlin Liang
1Department of Geography, University of Maryland, College Park, MD 20742, USA. kcwang@umd.edu
Science (New York, N.Y.)
|March 17, 2009
まとめ
エアロゾールによって引き起こされる地球規模のダミングは,1980年代半ばから増加し,太陽放射線を減少させました. ヨーロッパが明るくなっている一方で,他の大陸では視界が悪化し,暗くなっています.
科学分野:
- 大気科学 大気科学
- 気候科学 気候科学
- 環境科学 環境科学
背景:
- エアロゾールは,可視性を低下させることで,地球の表面の太陽放射線に大きく影響します.
- 太陽放射線の減少によって特徴づけられる地球規模のダミングは,1980年代半ばまで観察された.
研究 の 目的:
- 1973年から2007年までの陸上での逆視野の世界的な気候学を作成する.
- エアロゾールの光学的な深さと太陽放射線の影響を考慮して,視界の変化を解釈する.
主な方法:
- 35年間 (1973年~2007年) の土地における逆視野の分析.
- エアロゾールの光学的な深さと発生太陽放射線に関する可視性の傾向の解釈.
主要な成果:
- グローバルダミングへのエアロゾールの貢献は,分析された期間中,単調に増加しています.
- 1980年代半ば以降,欧州の知名度が向上しました (欧州の明るさ).
- 南アジア,東アジア,南アメリカ,オーストラリア,アフリカでは視界が低下し,陸上での地球全体の遮光が減少しています.
結論:
- この研究は,エアロゾールによる陸上でのグローバルダミングの増加の長期的な傾向を確立しています.
- 地域による可視性傾向の変動は明らかで,ヨーロッパは明るくなり,他の大陸は暗くなります.
- エアロゾールによる視界の変化は,地球規模で発生する太陽放射線に重大な影響を及ぼします.
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