强大的云流通合解释了贸易累积反的弱点
Raphaela Vogel1,2, Anna Lea Albright3, Jessica Vial3
1LMD/IPSL, Sorbonne Université, CNRS, Paris, France. raphaela.vogel@uni-hamburg.de.
Nature
|November 30, 2022
概括
贸易积云对于地球的冷却至关重要. 新的EUREC4A观测显示混合动力,而不是湿度,控制云层,反驳预测大量云层损失和高气候敏感性的模型.
科学领域:
- 大气科学
- 气候科学
- 云物理
背景情况:
- 贸易风地区的浅积云通过反射太阳辐射, 在地球的能量平衡中起着至关重要的作用.
- 这些云对气候变化的反应代表了气候预测的重大不确定性.
- 现有的气候模型往往将云层部分的变化与低热层混合联系起来,这表明云层干燥与混合增加.
研究的目的:
- 通过使用新的观测数据,研究贸易积云对气候变化的反应.
- 测试"混合-干燥假设",假设混合的增加导致云层的减少.
- 评估气候模型在模拟贸易累积云反方面的准确性.
主要方法:
- 采用了EUREC4A (阐明云循环合在气候中的作用) 实地活动的观察数据.
- 分析了云基部分,低热层混合和湿度之间的相互作用.
- 交易累积反模型与观察结果进行比较.
主要成果:
- 新的EUREC4A观测证实了混合干燥的假设.
- 由于混合而导致的阴度的动态增加比通过湿度进行的热力学控制更有影响.
- 中层层运动和引进速度对湿度有相反的影响,防止云干燥.
- 气候模型与EUREC4A数据之间在混合和多云的幅度,可变性和合方面发现了显著的差异.
结论:
- 夸大阴度与相对湿度对混合的依赖的模型被认为是不可信的.
- 这项研究支持并解释了在工艺规模上贸易累积反的弱点.
- 这些发现挑战了支持高气候敏感性的关键证据.
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