大气层顶部和地球表面热带气溶强迫的巨大差异
1Center for Clouds, Chemistry, and Climate, Scripps Institution of Oceanography, University of California at San Diego, La Jolla 92093, USA.
Nature
|May 16, 2000
概括
人类产生的气溶显著影响气候预测. 这项研究量化了热带气溶强迫,揭示了表面和大气顶部太阳辐射加热之间的三倍差异,表明了对水文循环的潜在影响.
科学领域:
- 大气科学 大气科学
- 气候科学 气候科学
- 环境科学 环境科学
背景情况:
- 人类产生的气溶在气候变化预测中占据了主要的不确定性.
- 对气溶辐射强迫的直接观测,特别是在热带地区,至关重要但有限.
- 热带气溶起源于南亚大陆,人们对其了解甚少.
研究的目的:
- 开发和介绍一种观测方法,以高精度 (+/- 5%) 量化气溶辐射强迫.
- 为了同时测量地球表面和大气层顶部的气溶强迫.
- 调查热带气溶对印度洋太阳辐射加热的影响.
主要方法:
- 使用校准的卫星辐射测量.
- 采用五个独立的表面辐射计进行地面验证.
- 在冬季 (1998-1999年) 的热带北印度洋清天空的量化太阳辐射加热.
主要成果:
- 观察到海洋表面太阳辐射加热的显著减少 (12-30 Wm(-2)).
- 在大气层顶部 (4-10 Wm(-2)) 测量了太阳辐射加热的较小减少.
- 确定了表面和大气顶部强迫之间的三倍差异,主要归因于烟尘吸收.
结论:
- 该研究提出了一种精确的方法来量化气溶强迫.
- 观察到的大面强迫和表面和TOA强迫之间的差异表明热带气溶可能会减缓水文循环.
- 研究结果强调了热带人为气溶在区域和全球气候动态中的重要作用.
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