重建的莫拉瓦河温暖季节流量的波动性增加,捷克共和国
Max C A Torbenson1,2, Rudolf Brázdil2,3, James H Stagge4
1Department of Geography, Johannes Gutenberg University, Mainz, Germany.
概括
树木环揭示了上个世纪中欧河流变化增加. 过去极低的流量并非完全由温度驱动,这表明未来的流量变化可能与当前的趋势有所不同.
科学领域:
- 水文学的水文学
- 古气候学 古气候学
- 登德罗年代学 登德罗年代学
背景情况:
- 在中欧,水文夏季极端 (低流量和洪水) 是重要的自然危险.
- 有限的测量数据在理解极端水文事件的变化方面造成了不确定性.
- 河流的低流影响了农业,工业和社会的供水.
研究的目的:
- 为了使用树环重建莫拉瓦河7月至9月底流的变化,从1745年到2018年.
- 提供欧洲第一个以树环为基础的基流重建.
- 用模拟流和历史记录来验证重建.
主要方法:
- 摩拉瓦河流域树环网络的编制.
- 开发一组基流重建的集合.
- 校准期长度和趋势影响的评估.
- 20世纪前估计的定量和定性验证.
主要成果:
- 重建显示,在过去的100年中,温暖季节的流量变化增加了.
- 大多数极端高低流量发生在仪器记录开始后.
- 1960年以后观察到的负基准流动趋势在长期记录中并非前所未有的.
结论:
- 仪器前的低流量趋势并不是主要由温度驱动的,与最近的趋势不同.
- 未来的低流量事件可能比仅由温度驱动模型预测的事件更严重.
- 树环数据为了解水文极端提供了重要的长期背景.
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