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观察到热带降雨量增加,然后空气穿过森林
D V Spracklen1, S R Arnold, C M Taylor
1School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK. d.v.spracklen@leeds.ac.uk
Nature
|September 7, 2012
概括
热带森林显著增加了降雨量. 森林砍伐减少了这种影响,亚马逊森林砍伐可能会使到2050年降雨量减少21%,这是由于水分回收减少.
科学领域:
- 环境科学 环境科学
- 大气科学 大气科学
- 生态生态学 生态生态学
背景情况:
- 植被通过调节水分,能量和微量气体的表面-大气交换来影响降水.
- 森林通过蒸发转化,对大气湿度做出了重大贡献,影响了降雨模式.
- 关于森林砍伐对降水的影响的先前研究产生了混合的结果,气候模型预测区域降低,一些观察表明局部增加.
研究的目的:
- 通过使用卫星数据和大气运输模式,评估森林对热带降雨的泛热带影响.
- 实证地证明植被覆盖和降水之间的联系.
- 预测亚马逊森林砍伐对该地区未来降雨的影响.
主要方法:
- 利用卫星遥感数据来测量热带降雨量和植被覆盖面.
- 嵌入模拟的大气运输模式以分析空气质量历史.
- 开发了植被和降雨之间的经验关系,并将它们应用于森林砍伐趋势.
主要成果:
- 超过60%的热带陆地表面显示,空气通过广泛的植被产生至少两倍的降雨量,相比空气通过稀疏的植被.
- 这种相关性支持了蒸发转化在维持植被地区大气湿度方面的作用.
- 预计亚马逊森林砍伐表明,到2050年,雨季降雨量将减少12%,干季降雨量将减少21%.
结论:
- 森林对于通过水分回收来维持热带降雨至关重要.
- 预计森林砍伐,特别是在亚马逊,将大大减少区域降雨量.
- 经验发现补充了气候模型的预测,强调了植被对气候调节的重要性.
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