解释和预测南半球旋驱动的喷气式飞机
Julia Mindlin1, Theodore G Shepherd2,3, Marisol Osman4,5,6
1Leipzig Institute for Meteorology, Leipzig 04103, Germany.
概括
全球变暖和远程驱动因素解释了南半球旋驱动喷气式 (EDJ) 转移. 气候模型准确地预测了度变化,但低估了EDJ的加强,突出了改善气候变化预测的必要性.
科学领域:
- 大气科学 大气科学
- 气候动力学 气候动力学
- 南半球气象学 南半球气象学
背景情况:
- 南半球旋转驱动喷气 (EDJ) 对区域天气模式和气候至关重要.
- 全球气候模型 (GCM) 在准确预测EDJ趋势方面面临挑战,原因是热带变暖和平流层变化等远程驱动因素的不确定性.
- 预测未来的EDJ行为对于了解区域气候影响至关重要.
研究的目的:
- 开发一个因果框架来归因过去的EDJ变化.
- 预测可能的EDJ的未来轨迹.
- 弥合气候变化归因与预测之间的差距.
主要方法:
- 结合观测数据,重新分析数据集和合模型对比项目 (CMIP) 的预测.
- 开发了一个因果推理框架,与气候故事集成.
- 分析了热带变暖和平流层极地加强对EDJ趋势的影响.
主要成果:
- 热带变暖在CMIP预测的下端正在进展.
- 平流层极地显示显著增强,影响观察到的EDJ趋势.
- 全球变暖占据了观察到的EDJ度转移的50%;远程驱动器占据了其他50%,GW归因不确定.
- GCMs准确地捕捉了观察到的度变化,但低估了EDJ的强化.
结论:
- 开发的因果关系框架有效地捕捉了观察到的EDJ趋势,在某些方面表现优于标准GCM.
- 将因果推理与气候故事情节相结合,为预测未来气候变化途径提供了一个物理基础的方法.
- 这种方法提高了我们做出更可靠的气候变化预测和了解区域气候影响的能力.
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