The Spatial and Temporal Variability of Meltwater Flow Paths: Insights From a Grid of Over 100 Snow Lysimeters
The Spatial and Temporal Variability of Meltwater Flow Paths: Insights From a Grid of Over 100 Snow Lysimeters
复制标题
融水流动路径的空间和时间变化：来自 100 多个雪蒸渗仪网格的见解
DOI：
10.1002/2017wr020866
复制
发表时间：
2018
影响因子：
5.4
通讯作者：
Erickson, T. A.
中科院分区：
文献类型：
--
作者：
Webb, R. W.;Williams, M. W.;Erickson, T. A.
融雪是水源地水文循环和生态系统动力学的重要组成部分。然而，通过雪的水流的物理过程是一个了解甚少的方面雪水文学的融水流动路径往往是非常复杂的。当融化的融水到达地层界面时，融水流动路径发散和会聚，从而产生高空间变化。此外，由于融化过程中发生的快速局部变质作用，积雪在时间上是不均匀的。这项研究使用了融雪蒸渗仪阵列在树线在北方科罗拉多的尼沃特岭研究领域。该阵列旨在解决1 300平方米面积上105个地点的基础流量的空间和时间变化问题。观察到的变异系数范围从0到几乎10表示更多的变化比以前观察到的，虽然这种变化在整个融化季节下降。融雪基流量也显着增加，积雪深度减少，显示集群模式，峰值在第3-5周的融雪季节。这些结果被解释为沿沿着雪层界面的融水流动。由于积雪在融化季节变得不那么分层，模式从优先流动路径转变为均匀的矩阵流。观测到的基底流量的相关范围对应于100 m2的平均代表性基本面积或10 m的特征长度。融雪模型表示的过程中，规模小于这将需要明确纳入融雪排放和融水流动路径通过模型像素之间的雪的空间变异性。
Snowmelt is an important part of the hydrologic cycle and ecosystem dynamics for headwater systems. However, the physical process of water flow through snow is a poorly understood aspect of snow hydrology as meltwater flow paths tend to be highly complex. Meltwater flow paths diverge and converge as percolating meltwater reaches stratigraphic layer interfaces creating high spatial variability. Additionally, a snowpack is temporally heterogeneous due to rapid localized metamorphism that occurs during melt. This study uses a snowmelt lysimeter array at tree line in the Niwot Ridge study area of northern Colorado. The array is designed to address the issue of spatial and temporal variability of basal discharge at 105 locations over an area of 1,300 m2. Observed coefficients of variation ranged from 0 to almost 10 indicating more variability than previously observed, though this variability decreased throughout each melt season. Snowmelt basal discharge also significantly increases as snow depth decreases displaying a cluster pattern that peaks during weeks 3–5 of the snowmelt season. These results are explained by the flow of meltwater along snow layer interfaces. As the snowpack becomes less stratified through the melt season, the pattern transforms from preferential flow paths to uniform matrix flow. Correlation ranges of the observed basal discharge correspond to a mean representative elementary area of 100 m2, or a characteristic length of 10 m. Snowmelt models representing processes at scales less than this will need to explicitly incorporate the spatial variability of snowmelt discharge and meltwater flow paths through snow between model pixels.
登录
查看更多内容
DOI：
--
发表时间：
1979
期刊：
影响因子：
--
作者：
S. Colbeck
通讯作者：
S. Colbeck
科罗拉多州北部积雪特性的盆地尺度空间变异性的驱动因素
DOI：
--
发表时间：
2014
期刊：
影响因子：
--
作者：
G. Sexstone;S. Fassnacht
通讯作者：
S. Fassnacht
美国科罗拉多州绿湖谷温暖积雪中的冰柱和冰冻溪流
DOI：
--
发表时间：
2000
期刊：
影响因子：
--
作者：
M. Williams;M. Rikkers;W. Pfeffer
通讯作者：
W. Pfeffer
影响因子：
5.4
作者：
Bales, Roger C.;Molotch, Noah P.;Dozier, Jeff
通讯作者：
Dozier, Jeff
迈向空间统计理论：又向前迈出了一步
DOI：
--
发表时间：
2010
期刊：
影响因子：
--
作者：
D. Griffith
通讯作者：
D. Griffith