The numerical method for estimating soil moisture transport coefficients in land surface models (LSMs) is evaluated through comparison to a weighted-average method based on successive steady states [Warrick, 1991] and a proposed new scheme [Dong and Wang, 1997]. The focus is on situations with large gradients of soil moisture. The reference cases used to evaluate the performance of the various ...

Some essential features of the terrestrial hydrologic cycle and ecosystem response are singled out by confronting empirical observations of the soil water balance of different ecosystems with the results of a stochastic model of soil moisture dynamics. The simplified framework analytically describes how hydroclimatic variability (especially the frequency and amount of rainfall events) concurs w...

Lateral surface/subsurface flow and their connectivity play a significant role in redistributing soil water, which has a direct effect on biological, chemical, and geomorphological processes in the root zone (~1m). However, most of the land surface models neglect the horizontal exchanges of water at the grid or subgrid scales, focusing only on the vertical exchanges of water as one-dimensional ...

* Corresponding author ** This study is supported by the ‘Ministère Luxembourgeois de la Culture, de l’Enseignement Supérieur et de la Recherche’ and the French Space Agency (CNES) Abstract –Owing to the non-linearity of the rainfallinfiltration-runoff relationship, soil water content in the river basin represents a key parameter to be monitored for flood management purposes. Remote sensing obs...

The major problem in the assessment of relationships between rainfall and runoff occurs when a study is carried out in ungauged watersheds in the absence of hydro-climatic data. This study aims to evaluate the applicability of Natural Resources Conservation Service-Curve Number (NRCS-CN) method together with GIS in estimating runoff depth in a mountainous watershed. The study was carried out in...

soil and water assessment tool model, swat, uses different layers of watershed data which out of soil layer is the important one. soil layer data should be extracted from detailed soil maps. in most developing countries including iran, these detailed maps are not available except for irrigation districts and rarely for dry land farming areas and also for some strategic places of development pur...

Catchment classification is an efficient method to synthesize our understanding of how climate variability and catchment characteristics interact to define hydrological response. One way to accomplish catchment classification is to empirically relate climate and catchment characteristics to hydrologic behavior and to quantify the skill of predicting hydrologic response based on the combination ...

Hydrologic models can be categorized as being either Newtonian or Darwinian in nature. The Newtonian approach requires a thorough understanding of the individual physical processes acting in a watershed in order to build a detailed hydrologic model based on the conservation equations. The Darwinian approach seeks to explain the behavior of a hydrologic system as a whole by identifying simple an...

Imparting knowledge of the physical processes of a system to a model and determining a set of parameter values for a hydrologic or water quality model application (i.e., parameterization) are important and difficult tasks. An exponential increase in the literature has been devoted to the use and development of these models over the years. Few articles, however, have been devoted to developing g...