八个世纪的北大西洋大气变化大气的变化
1Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL 33149, USA. National Oceanic and Atmospheric Administration Paleoclimatology Program and the Institute for Arctic and Alpine Research, University of Colorado, B.
概括
热带大西洋气候在825年的变化揭示了一个关键的十年模式. 百年级的变化和大约700年前北半球气候转变的可能性也很明显.
科学领域:
- 古气候学 古气候学
- 海洋 - 大气动力学 海洋 - 大气动力学
- 热带气象学 热带气象学
背景情况:
- 热带北大西洋气候受过海风,热带融合区 (ITCZ) 和海面温度的影响.
- 了解过去的气候变化对于预测未来的气候趋势至关重要.
研究的目的:
- 用高分辨率的加勒比海沉积物数据重建过去825年的热带上升和贸易风的变化.
- 调查热带大西洋气候变化的主要模式.
主要方法:
- 来自加勒比海的高分辨率沉积物核心的分析.
- 亚十年级的古气候重建.
主要成果:
- 证实了大西洋变化的显著十年 (12至13年) 模式,可能是由海洋与大气的合驱动的.
- 有证据表明,热带大西洋的百年级变化很大.
- 没有明确的十年间变化模式被确定为该地区的特征.
结论:
- 热带大西洋表现出显著的十年和世纪规模的气候变化.
- 该地区可能受到大约700年前北半球主要气候变化的影响.
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