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由于北极地区云层增强的短波冷却效应,降低了雪和冰的融化
Annan Chen1, Chuanfeng Zhao1, Haotian Zhang1
1Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China.
National science review
|May 7, 2025
概括
北极的雪和冰损失放大了云的辐射效应,导致冷却,这部分减缓了融化. 尽管如此,总体上雪和冰的损失仍在继续,影响着地球的能量平衡.
科学领域:
- 地球科学 地球科学 地球科学
- 气候科学 气候科学
- 大气科学 大气科学
背景情况:
- 云和表面的白度是地球能量平衡的关键组成部分.
- 北极雪/冰融对短波云辐射效应 (CRE) 的影响尚不清楚.
- 了解这些影响对于气候变化预测至关重要.
研究的目的:
- 分析北极地区的雪/冰覆盖面 (SIC) 变化.
- 调查SIC变化对云辐射效应 (CRE) 的影响.
- 评估过去,现在和未来的北极雪/冰损失和CRE的情景.
主要方法:
- 对2000年至2020年的雪/冰覆盖面 (SIC) 数据进行分析.
- 计算大气和表面顶部云辐射效应 (CRE) 的变化.
- 根据不同的社会经济路径 (SSP 245和585) 检查历史 (1850-1915) 和未来 (2015年后) 趋势.
主要成果:
- 从2000年到2020年,北极的SIC下降了-0.058/十年.
- 这导致CRE变化为-1.25 ± 0.49 W/m2/十年 (TOA) 和-0.21 ± 0.20 W/m2/十年 (表面).
- 在SSP 245和585下,海冰覆盖面和CRE在2015年后大幅下降.
结论:
- 雪/冰损失放大了云引起的短波冷却.
- 这种增强的冷却效应提供了对进一步化的部分阻力.
- 这种反机制并不能阻止北极地区的雪和冰总体损失.
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