...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Earth Surface Processes and Landforms: The journal of the British Geomorphological Research Group >Linking frequency of rainstorms, runoff generation and sediment transport across hyperarid talus-pediment slopes
【24h】

Linking frequency of rainstorms, runoff generation and sediment transport across hyperarid talus-pediment slopes

机译：带有暴雨频率，跨越式滑石滑坡的频率

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Documenting hillslope response to hydroclimatic forcing is crucial to our understanding of landscape evolution. The evolution of talus-pediment sequences (talus flatirons) in arid areas was often linked to climatic cycles, although the physical processes that may account for such a link remain obscure. Our approach is to integrate field measurements, remote sensing of rainfall and modeling to link between storm frequency, runoff, erosion and sediment transport. We present a quantitative hydrometeorological analysis of rainstorms, their geomorphic impact and their potential role in the evolution of hyperarid talus-pediment slopes in the Negev desert, Israel. Rainstorm properties were defined based on intensity-duration-frequency curves and using a rainfall simulator, artificial rainstorms were executed in the field. Then, the obtained measured experimental results were up-scaled to the entire slope length using a fully distributed hydrological model. In addition, natural storms and their hydro-geomorphic impacts were monitored using X-band radar and time-lapse cameras. These integrated analyses constrain the rainfall threshold for local runoff generation at rain intensity of 14 to 22 mm h(-1) for a duration of five minutes and provide a high-resolution characterization of small-scale runoff-generating rain cells. The current frequency of such runoff-producing rainstorms is similar to 1-3 per year. However, extending this local value into the full extent of hillslope runoff indicates that it occurs only under rainstorms with >= 100-years return interval, or 1% annual exceedance probability. Sheetwash efficiency rises with downslope distance; beyond a threshold distance of similar to 100 m, runoff during rainstorms with such annual exceedance probability are capable of transporting surface clasts. The erosion efficiency of these discrete rare events highlights their potential importance in shaping the landscape of arid regions. Our results support the hypothesis that a shift in the properties and frequency of extreme events can trigger significant geomorphic transitions in areas that remained hyperarid during the entire Quaternary. (c) 2020 John Wiley & Sons, Ltd.
机译：记录山坡对水皮强迫的反应对于我们对景观演变的理解至关重要。干旱地区的缩略图序列（Talus Flatirons）的演变通常与气候循环相连，尽管可能对这种环节进行解释的物理过程仍然模糊不清。我们的方法是整合现场测量，遥感降雨和建模，以在风暴频率，径流，侵蚀和沉积物运输之间联系。我们展示了暴雨的定量水质气象分析，其几何影响及其在以色列内德夫沙漠的超级岩石山地山坡演变中的潜在作用。利用强度持续时间曲线和使用降雨模拟器来定义暴雨性质，在该领域执行人工暴雨。然后，使用完全分布的水文模型将获得的测量的实验结果上缩放到整个斜坡长度。此外，使用X波段雷达和延时摄像机监测天然风暴及其水力磨碎的影响。这些综合分析限制了在雨强度为14至22mm H（-1）的局部径流的降雨阈值，持续为五分钟，并提供小型径流产生雨细胞的高分辨率表征。此类径流导出暴雨的当前频率类似于每年1-3。但是，将该本地值扩展到Hillslope Runoff的全部范围内表明它仅在暴政下发生> = 100年返回间隔，或年度超标概率1％。洗涤效率随下坡距离;除了类似于100米的阈值距离之外，具有此类年度超标概率的暴雨期间的径流能够运输表面泥浆。这些离散罕见事件的侵蚀效率突出了它们在塑造干旱地区景观方面的潜在重要性。我们的结果支持假设，即极端事件的性质和频率的变化可以触发在整个第四纪期间剩余的大型过渡的区域中的显着地貌过渡。 （c）2020 John Wiley＆Sons，Ltd。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号