通过地形绝缘与高原加热对南亚季风的支配性控制
William R Boos1, Zhiming Kuang
1Department of Earth and Planetary Sciences.
Nature
|January 16, 2010
概括
在西藏高原的西藏高原.
科学领域:
- 气候学 气候学 气候学
- 大气科学 大气科学
- 地质物理学 地质物理学
背景情况:
- 西藏高原的高度传统上被认为是南亚夏季季风的主要驱动因素.
- 以前的假设将高原升高与地质时间尺度气候变化联系在一起.
- 目前的气候观测显示,印度的上热带热量达到顶峰,而不是高原,质疑其主导作用.
研究的目的:
- 调查西藏高原作为南亚夏季季风的热源的实际作用.
- 重新评估山脉,特别是喜马拉雅山脉对季风动态的影响.
- 了解陆地表面和辐射强迫对区域气候的影响.
主要方法:
- 利用大气模型模拟季风循环,并没有西藏高原的热力强迫.
- 在模型实验中保存了喜马拉雅山脉和相邻山脉的狭窄地形.
- 分析了观测数据和模型输出,以评估区域气候反应.
主要成果:
- 消除西藏高原的加热效应并没有显著改变南亚大规模的夏季季风循环.
- 发现高原的加热增加了沿其南部边缘的当地降雨量.
- 喜马拉雅山脉和相关的山脉在维持季风方面显得至关重要,因为它们能将印度温暖的空气从寒冷的热带地区隔离出来.
结论:
- 这项研究挑战了长期以来关于西藏高原作为南亚夏季季风的主要驱动因素的观点.
- 山岳地形,特别是喜马拉雅山脉,在塑造季风强度方面发挥着至关重要的作用.
- 这些发现需要重新解释过去气候对地形升起和未来气候变化影响的反应.
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