Temporal stability of surface soil moisture in the Little Washita River watershed and its applications in satellite soil moisture product validation
Temporal stability of surface soil moisture in the Little Washita River watershed and its applications in satellite soil moisture product validation
复制标题
DOI：
10.1016/j.jhydrol.2005.08.020
复制
发表时间：
2006-05-30
影响因子：
6.4
通讯作者：
Heathman, G
中科院分区：
文献类型：
--
作者：
Cosh, MH;Jackson, TJ;Heathman, G
时间稳定性的概念可以用来识别持续的土壤水分模式，并从选定的代表性传感器位置估计大尺度平均值。准确和有效地估计大尺度表层土壤水分是土壤水分卫星验证计划的一个主要组成部分。然而，在大网格尺度上监测土壤表面是困难的。作为AQUA卫星先进微波扫描辐射计(AMSR)验证计划的一部分，2002年在美国俄克拉何马州的小沃什托河流域安装了土壤湿度传感器网络。与2003年土壤水分试验(SMEX03)的数据一起，该网络将为卫星土壤水分产品验证提供有价值的数据集。分析表明，大多数网络传感器在多个尺度上都是时间稳定的，其中4个站点具有代表性，偏差可以忽略不计，对分水岭平均值的标准偏差很小。作为分析的一部分，验证了为大规模土壤水分采样活动建立的协议，例如在土壤水分实验(SNMX)中。分析表明，基于6个采样点的栅格比例尺估算是合理和准确的。时间稳定性是土壤水分网络分析的一个有价值的工具，可以为大规模卫星验证提供一个有效的手段。(C)2005 Elsevier B.V.保留所有权利。
The concept of temporal stability can be used to identify persistent soil moisture patterns and estimate the large scale average from select representative sensor locations. Accurate and efficient estimation of large-scale surface soil moisture is a primary component of soil moisture satellite validation programs. However, monitoring the soil surface at large grid scales is difficult. As part of the aqua satellite advanced microwave scanning radiometer (AMSR) Validation Program, a soil moisture sensor network was installed in the little Washita river watershed in Oklahoma, USA in 2002. Along with data from the soil moisture experiment 2003 (SMEX03), this network will provide a valuable dataset for satellite soil moisture product validation. Analysis shows that most of the network sensors are temporally stable at multiple scales and four sites are identified as representative with negligible bias and small standard deviation to the watershed mean. As part of this analysis, the protocols established for large-scale soil moisture sampling campaigns such as in the soil moisture experiments (SNMX) are validated. This analysis showed that basing grid scale estimates on six sampling points is reasonable and accurate. Temporal stability is shown to be a valuable tool for soil moisture network analysis and can provide an efficient means to large-scale satellite validation. (c) 2005 Elsevier B.V. All rights reserved.