在云运动向量中检测到的大气循环的十年变化
Larry Di Girolamo1, Guangyu Zhao2, Gan Zhang2
1Department of Climate, Meteorology & Atmospheric Sciences, University of Illinois Urbana-Champaign, Urbana, IL, USA. gdi@illinois.edu.
Nature
|July 9, 2025
概括
卫星数据显示,在过去的20年里,地球大气循环发生了重大变化. 云的移动速度有所增加,表明天气模式的变化和潜在的气候模型偏差.
科学领域:
- 大气科学
- 气候科学
- 遥感技术
背景情况:
- 全球的天气模式受到大气循环的影响,
- 现有的气候模型和重新分析数据显示观察到的循环变化存在差异.
- 用独立的气候质量测量验证对于理解这些变化至关重要.
研究的目的:
- 使用卫星数据检测和验证热层循环的统计学意义上的变化.
- 根据独立观察,评估广泛使用的再分析产品的准确性.
- 为改善气候模型提供基准.
主要方法:
- 使用多角度成像光谱仪 (MISR) 的卫星观测,高度解析的云运动向量.
- 分析了二十年来热带和极地阵线的上层热带云运动速度和度变化.
- 将MISR数据与ERA5再分析风进行比较.
主要成果:
- 观测到上层热带中度云运动速度的统计显著增加 (高达4米/秒/十年).
- 在北半球热带 (0.42°/十年) 和极地阵线 (0.37°/十年) 中检测到极移.
- 在MISR和ERA5气候学之间发现了良好的一致性,但在上层热带层发现了可能的ERA5偏差.
结论:
- MISR卫星数据提供了重要的独立证据,证明了热层循环的重大变化.
- 这些发现突显了当前再分析产品的潜在偏差,特别是在上层热层.
- 这些观测对于完善气候模型和改善我们对气候变化影响的理解至关重要.
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