透气估计中的不确定性
A M J Coenders-Gerrits1, R J van der Ent1, T A Bogaard1
1Water Resources Section, Delft University of Technology, Stevinweg 1, 2628 CN Delft, The Netherlands.
Nature
|February 14, 2014
概括
植物透气是植物的透气.
科学领域:
- 水文学的水文学
- 生态生态学 生态生态学
- 气候科学 气候科学
背景情况:
- 植物透气与其他来源 (如土壤,水体,树冠拦截) 的蒸发对全球水循环的相对贡献是一个长期的辩论.
- 之前的研究,包括Jasechko等. (2013年) 提出了透气在土地蒸发中的重要作用.
- 准确的量化对于理解陆地与大气相互作用和改善气候模型至关重要.
研究的目的:
- 批判性地评估Jasechko等人估计的全球透气比率. (2013年) 的时间.
- 重新评估植物透气对土地总蒸发的贡献.
- 突出数据选择和不确定性量化对水文估计的影响.
主要方法:
- 重新分析全球蒸发数据,考虑其他输入数据集.
- 对与水文测量相关的不确定性进行保守的核算.
- 修订过的透气估计与现有气候模型输出结果的比较.
主要成果:
- 当使用替代数据和保守的不确定性评估时,估计的全球透气率显著降低,扩大到35-80%
- 这一修订的范围表明,与最初提出的80-90%相比,透气的占主导作用较小.
- 这些发现表明观测数据和气候模型假设之间的潜在差异.
结论:
- 植物透气的全球重要性需要通过更全面的采集区规模数据进行进一步的研究.
- 减少水文测量的不确定性对于调整观测数据与气候模型预测至关重要.
- 需要继续进行研究,以完善我们对全球水循环和陆地-大气反的理解.
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