隐形的船只痕迹显示大云对气溶的敏感性
Peter Manshausen1, Duncan Watson-Parris2, Matthew W Christensen3
1Atmospheric, Oceanic and Planetary Physics, Department of Physics, University of Oxford, Oxford, UK. peter.manshausen@physics.ox.ac.uk.
Nature
|October 5, 2022
概括
即使没有可见的船舶轨迹, 气溶排放也会显著改变云的特性. 一种新的方法揭示了水滴数量和液态水的增加,
科学领域:
- 大气科学
- 气候科学
- 气溶与云的相互作用
背景情况:
- 云的反射性受到气溶粒子作为凝结核的影响.
- 人类引起的气溶增加了撞击云滴数量,液态水和云分数,但存在很大的不确定性.
- 只有很小一部分受污染的云呈现出这种现象.
研究的目的:
- 量化航运排放对云的影响,即使没有可见的船舶轨迹.
- 开发一种超出卫星可见船舶轨道观测的新方法来评估气溶与云的相互作用.
- 调查航运对大西洋贸易积聚区域的云的影响.
主要方法:
- 开发一种新的方法来量化航运排放的气溶与云的相互作用.
- 分析大西洋贸易累积区域的云特性,重点关注最少可见船舶轨迹的地区.
- 直接检测出海产生的云特性变化.
主要成果:
- 气溶的排放大大改变了云的特性, 即使船只的轨迹是看不见的.
- 这种新方法检测出云滴数度增加,并且在没有可见的痕迹的情况下产生了积极的液态水反应.
- 在大西洋贸易累积地区直接观察到由航运引起的云特性变化.
结论:
- 之前仅依靠可见船舶轨迹的研究可能存在选择偏差.
- 观察到强烈的液态水路反应意味着航运带来的气溶降温效应更大.
- 这种增强的冷却效应可能会掩盖比当前温度趋势更高的气候敏感性.
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