The February 2000 floods on the Letaba River, South Africa: an examination of magnitude and frequency
The February 2000 floods on the Letaba River, South Africa: an examination of magnitude and frequency
复制标题
2000 年 2 月南非莱塔巴河洪水：对震级和频率的考察
DOI：
--
复制
发表时间：
2001
期刊：
影响因子：
--
通讯作者：
A. Large
中科院分区：
文献类型：
--
作者：
B. P. Moon;A. Large
很难准确估计2000年2月影响南部非洲的洪水的严重程度，因为洪水损坏了受影响河流上的大多数测站。通过模拟峰值水流的水力和几何特征，并将其与河道的粗糙度联系起来，可以估计克鲁格国家公园莱塔巴河经历的峰值流量。峰值水面坡度数据是由渠道类型断裂处的碎屑和泥线测量确定的。这些数据与公布的不同渠道类型的大流量渠道阻力系数相结合，以生成位于支流之间的11个不同横断面的峰值流量估计值，以便估计分流域的贡献。2000年2月，在黑鹭大坝附近(公园西部)，流量达到峰值，约为西北4000度，并在奥立夫茨河汇合处上游增加到约2000米？S。与仪表记录的比较表明，2000年2月的峰值比随后40年中的任何流量都要高。
Accurate estimates of the magnitude of the floods that affected southern Africa in February 2000 are difficult to obtain since floodwaters damaged the majority of gauging stations on affected rivers. It is possible to estimate the peak discharge experienced in the Letaba River in the Kruger National Park by simulating the hydraulic and geometric characteristics of the peak flow and relating these to the roughness of the channel. Peak water surface slope data were determined from debris and mudline measurements at breaks in channel type. These data are combined with published high-flow channel resistance coefficients for different channel types to generate peak flow estimates for eleven different cross-sections, located between tributaries to allow for sub-catchment contributions to be estimated. In February 2000 flow peaked at approximately 4000 nWs near to Black Heron Dam (in the west of the park), and increased to approximately POOOm^s just upstream of the confluence with the Olifants River. Comparison with gauge records indicates that the February 2000 peak was higher than any flow during the proceeding four decades.