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极端的平流层波浪活动作为北美地区寒冷事件的预兆
Xiuyuan Ding1, Gang Chen1, Pengfei Zhang2
1Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, Los Angeles, CA USA.
概括
极端的平流层波事件在北美寒冷时期之前发生. 这种连接在5-25天后发生,提高了严冬天气和极端寒冷的可预测性.
科学领域:
- 大气科学 大气科学
- 气候动力学 气候动力学
- 气象学 天气学
背景情况:
- 北美地区的极端寒冷事件,比如2021年2月的寒波,可能与平流层极地延伸有关.
- 对平流层对表面温度异常的影响的确切贡献和时间范围尚不清楚.
研究的目的:
- 为了研究平流层波动活动与北美极端寒冷之间的联系.
- 开发一种简单的平流层波活动测量方法,适用于重新分析和气候模型.
主要方法:
- 介绍了一种新的,简单的平流层波动活动度量.
- 对观测数据和气候模型输出的分析.
- 理想化的大气模型模拟与一个明确的平流层.
主要成果:
- 极端的平流层波事件与北美温暖和寒冷之间的季内波动相关.
- 强烈的平流层波浪活动在5-25天后北美极寒风险增加之前.
- 垂直波合被认为是将平流层活动与寒冷周期联系起来的机制.
结论:
- 平流层波浪活动显著影响北美表面的天气,特别是极端寒冷.
- 这些发现增强了对高影响冬季天气事件可预测性的理解.
- 一个新的指标有助于分析平流层在气候研究和建模中的影响.
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