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Updated: Jun 10, 2025

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北极海冰上的夏季雪是由北极振荡调节的
Melinda A Webster1, Aku Riihelä2, Sahra Kacimi3
1Polar Science Center, Applied Physics Laboratory, University of Washington, Seattle, WA USA.
概括
北极振荡影响北极海冰的夏季雪深,在积极阶段增加积累和白度. 自2007年以来,这种影响已经减弱,可能会改变未来海冰融化的动态.
科学领域:
- *气候学和冷层科学
- * 大气科学与海洋学
背景情况:
- * 自20世纪70年代以来,北极海冰显著稀释和减少.
- *海冰上的雪覆盖对于调节太阳吸收至关重要,因为它的白度很高,减轻了融化和海洋变暖.
- * 夏季北极海冰雪深度变化的主要驱动因素在很大程度上是未知的.
研究的目的:
- * 调查北极振荡 (AO) 对夏季北极海冰雪深度变化的影响.
- *使用多个数据源和建模技术分析1980年至2020年期间.
- * 了解AO阶段如何影响积雪,表面白度和随后的海冰状况.
主要方法:
- *利用大气再分析数据来评估气候条件.
- * 采用雪模型来模拟雪的深度和积累.
- * 包含卫星数据用于观测验证.
主要成果:
- *北极振荡的积极阶段与北极夏季增加的积雪 (北极附近高达4.5厘米) 和更高的表面白度相关.
- * 积极的AO阶段与更频繁和更强烈的北极旋风,更低的上层温度和更多的降雪有关.
- *这些条件有助于夏季更持久的雪地覆盖,可能减少海冰融化和海洋变暖.
结论:
- *北极振荡在调节夏季雪深和北极海冰的白度方面发挥着重要作用.
- *北极振荡对北极海冰雪覆盖的影响自2007年以来呈现疲软趋势.
- *未来的北极变暖和海冰流失可能会改变北极振荡和雪地覆盖动态之间的关系,影响气候反.
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