Physically based modeling of rainfall-triggered landslides: a case study in the Luquillo forest, Puerto Rico

Abstract. This paper presents the development of a rainfall-triggered landslide module within an existing physically based spatially distributed ecohydrologic model. The model, tRIBS-VEGGIE (Triangulated Irregular Networks-based Real-time Integrated Basin Simulator and Vegetation Generator for Interactive Evolution), is capable of a sophisticated description of many hydrological processes; in particular, the soil moisture dynamics are resolved at a temporal and spatial resolution required to examine the triggering mechanisms of rainfall-induced landslides. The validity of the tRIBS-VEGGIE model to a tropical environment is shown with an evaluation of its performance against direct observations made within the study area of Luquillo Forest. The newly developed landslide module builds upon the previous version of the tRIBS landslide component. This new module utilizes a numerical solution to the Richards' equation (present in tRIBS-VEGGIE but not in tRIBS), which better represents the time evolution of soil moisture transport through the soil column. Moreover, the new landslide module utilizes an extended formulation of the factor of safety (FS) to correctly quantify the role of matric suction in slope stability and to account for unsaturated conditions in the evaluation of FS. The new modeling framework couples the capabilities of the detailed hydrologic model to describe soil moisture dynamics with the infinite slope model, creating a powerful tool for the assessment of rainfall-triggered landslide risk.

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Physically based modeling of rainfall-triggered landslides: a case study in the Luquillo Forest, Puerto Rico

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-10-1333-2013 ◽

2013 ◽

Vol 10 (1) ◽

pp. 1333-1373 ◽

Cited By ~ 1

Author(s):

C. Lepore ◽

E. Arnone ◽

L. V. Noto ◽

G. Sivandran ◽

R. L. Bras

Keyword(s):

Soil Moisture ◽

Soil Column ◽

Hydrologic Model ◽

Richards Equation ◽

Landslide Risk ◽

Modeling Framework ◽

Soil Moisture Dynamics ◽

Physically Based ◽

Spatially Distributed ◽

Moisture Dynamics

Abstract. This paper presents the development of a rainfall-triggered landslide module within a physically based spatially distributed ecohydrologic model. The model, Triangulated Irregular Networks Real-time Integrated Basin Simulator and VEGetation Generator for Interactive Evolution (tRIBS-VEGGIE), is capable of a sophisticated description of many hydrological processes; in particular, the soil moisture dynamics is resolved at a temporal and spatial resolution required to examine the triggering mechanisms of rainfall-induced landslides. The validity of the tRIBS-VEGGIE model to a tropical environment is shown with an evaluation of its performance against direct observations made within the Luquillo Forest (the study area). The newly developed landslide module builds upon the previous version of the tRIBS landslide component. This new module utilizes a numerical solution to the Richards equation to better represent the time evolution of soil moisture transport through the soil column. Moreover, the new landslide module utilizes an extended formulation of the Factor of Safety (FS) to correctly quantify the role of matric suction in slope stability and to account for unsaturated conditions in the evaluation of FS. The new modeling framework couples the capabilities of the detailed hydrologic model to describe soil moisture dynamics with the Infinite Slope model creating a powerful tool for the assessment of landslide risk.

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Gravitational and capillary soil moisture dynamics for distributed hydrologic models

Hydrology and Earth System Sciences ◽

10.5194/hess-19-1857-2015 ◽

2015 ◽

Vol 19 (4) ◽

pp. 1857-1869 ◽

Cited By ~ 9

Author(s):

A. Castillo ◽

F. Castelli ◽

D. Entekhabi

Keyword(s):

Soil Moisture ◽

Unsaturated Soils ◽

Soil Layer ◽

Hydrologic Model ◽

Local Scale ◽

Distributed Model ◽

Limiting Factor ◽

Soil Physics ◽

Soil Moisture Dynamics ◽

Moisture Dynamics

Abstract. Distributed and continuous catchment models are used to simulate water and energy balance and fluxes across varied topography and landscape. The landscape is discretized into computational plan elements at resolutions of 101–103 m, and soil moisture is the hydrologic state variable. At the local scale, the vertical soil moisture dynamics link hydrologic fluxes and provide continuity in time. In catchment models these local-scale processes are modeled using 1-D soil columns that are discretized into layers that are usually 10−3–10−1 m in thickness. This creates a mismatch between the horizontal and vertical scales. For applications across large domains and in ensemble mode, this treatment can be a limiting factor due to its high computational demand. This study compares continuous multi-year simulations of soil moisture at the local scale using (i) a 1-pixel version of a distributed catchment hydrologic model and (ii) a benchmark detailed soil water physics solver. The distributed model uses a single soil layer with a novel dual-pore structure and employs linear parameterization of infiltration and some other fluxes. The detailed solver uses multiple soil layers and employs nonlinear soil physics relations to model flow in unsaturated soils. Using two sites with different climates (semiarid and sub-humid), it is shown that the efficient parameterization in the distributed model captures the essential dynamics of the detailed solver.

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Assimilating scatterometer soil moisture data into conceptual hydrologic models at the regional scale

Hydrology and Earth System Sciences ◽

10.5194/hess-10-353-2006 ◽

2006 ◽

Vol 10 (3) ◽

pp. 353-368 ◽

Cited By ~ 116

Author(s):

J. Parajka ◽

V. Naeimi ◽

G. Blöschl ◽

W. Wagner ◽

R. Merz ◽

...

Keyword(s):

Soil Moisture ◽

Regional Scale ◽

Hydrologic Model ◽

Hydrologic Models ◽

Ungauged Catchments ◽

Soil Moisture Dynamics ◽

Model Efficiency ◽

The Relationship ◽

Runoff Model ◽

Moisture Dynamics

Abstract. This paper examines the potential of scatterometer data from ERS satellites for improving hydrological simulations in both gauged and ungauged catchments. We compare the soil moisture dynamics simulated by a semidistributed hydrologic model in 320 Austrian catchments with the soil moisture dynamics inferred from the satellite data. The most apparent differences occur in the Alpine areas. Assimilating the scatterometer data into the hydrologic model during the calibration phase improves the relationship between the two soil moisture estimates without any significant decrease in runoff model efficiency. For the case of ungauged catchments, assimilating scatterometer data does not improve the daily runoff simulations but does provide more consistent soil moisture estimates. If the main interest is in obtaining estimates of catchment soil moisture, reconciling the two sources of soil moisture information seems to be of value because of the different error structures.

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Simplified stochastic soil-moisture models: a look at infiltration

Hydrology and Earth System Sciences ◽

10.5194/hess-10-861-2006 ◽

2006 ◽

Vol 10 (6) ◽

pp. 861-871 ◽

Cited By ~ 17

Author(s):

J. R. Rigby ◽

A. Porporato

Keyword(s):

Soil Moisture ◽

Time Scale ◽

Rectangular Pulse ◽

Short Time Scale ◽

Soil Moisture Dynamics ◽

Physically Based ◽

Probabilistic Structure ◽

Averaged Model ◽

Moisture Dynamics ◽

Daily Time

Abstract. A simplified, vertically-averaged model of soil moisture interpreted at the daily time scale and forced by a stochastic process of instantaneous rainfall events is compared with a vertically-averaged model which uses a non-overlapping rectangular pulse rainfall model and a more physically based description of infiltration. The models are compared with respect to the importance of short time-scale (intra-storm) variable infiltration in determining the probabilistic structure of soil-moisture dynamics at the daily time-scale. Differences in approach to infiltration modelling show only minor effects on the probabilistic structure of soil-moisture dynamics as simulated in the two models. The partitioning of losses during a single rainfall event are examined closely and the conditions under which surface-controlled runoff is significant, as a proportion of total losses, are delineated.

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Assimilating scatterometer soil moisture data into conceptual hydrologic models at the regional scale

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-2-2739-2005 ◽

2005 ◽

Vol 2 (6) ◽

pp. 2739-2786 ◽

Cited By ~ 3

Author(s):

J. Parajka ◽

V. Naeimi ◽

G. Blöschl ◽

W. Wagner ◽

R. Merz ◽

...

Keyword(s):

Soil Moisture ◽

Regional Scale ◽

Hydrologic Model ◽

Hydrologic Models ◽

Ungauged Catchments ◽

Soil Moisture Dynamics ◽

Model Efficiency ◽

The Relationship ◽

Runoff Model ◽

Moisture Dynamics

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Evaluation of Flux-PIHM, a physically-based land surface hydrologic model in an agricultural watershed

10.22541/au.161007744.48064604/v1 ◽

2021 ◽

Author(s):

Yuting Smeglin ◽

Yuning Shi ◽

Jason Kaye ◽

Caitlin Hodges ◽

Qicheng Tang ◽

...

Keyword(s):

Soil Moisture ◽

Land Surface ◽

Deciduous Forest ◽

Soil Column ◽

Hydrologic Model ◽

Agricultural Watershed ◽

Sensible Heat ◽

Spatially Distributed ◽

The Impact ◽

Shale Hills

An agricultural watershed, Cole Farm, was established as the newest of the three subcatchments in the Susquehanna Shale Hills Critical Zone Observatory (SSHCZO) in 2017. The catchment contains mostly pasture and crops, with a small portion of deciduous forest. The observations in Cole Farm afford an opportunity to test the spatially distributed land surface hydrologic model, Flux-PIHM, in farmland for the first time. In this study, we calibrated the model to only discharge and groundwater level observations at Cole Farm, but it’s able to capture the variations and magnitudes of soil moisture, latent heat (LE) and sensible heat (H) fluxes. Modeled soil moisture on the ridge top matched the observations well, but modeled soil moisture in the mid-slope differed from observations likely due to the existence of fragipan in the soil column. Flux-PIHM reproduced the seasonality and diurnal variations of watershed-average evapotranspiration (ET), sensible heat flux (H), though modeled ET in summer is about 25% greater than tower ET. To study the impact of land cover on hydrology, we imposed two different LAI forcings to the model: spatially distributed versus uniform LAI. Spatially distributed LAI produced higher ET and lower soil moisture in the forested part of the watershed due to higher LAI of deciduous forest in comparison to crops and pasture. But the impact of different LAI forcings on discharge was small. We further compared the water budget simulated by Flux-PIHM in the agricultural watershed (Cole Farm) to a forested watershed (Shale Hills). Flux-PIHM simulated less discharge and higher transpiration and bare soil evaporation in the Cole Farm watershed relative to Shale Hills watershed. Our work shows that with a few key observations, Flux-PIHM can be calibrated to simulate agricultural watershed hydrology, but spatially distributed LAI and soils data are needed to capture the spatial variations in soil moisture and ET.

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Gravitational and capillary soil moisture dynamics for hillslope-resolving models

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-11-7133-2014 ◽

2014 ◽

Vol 11 (6) ◽

pp. 7133-7168 ◽

Cited By ~ 1

Author(s):

A. Castillo ◽

F. Castelli ◽

D. Entekhabi

Keyword(s):

Soil Moisture ◽

Unsaturated Soils ◽

Soil Layer ◽

Hydrologic Model ◽

Local Scale ◽

Distributed Model ◽

Limiting Factor ◽

Soil Physics ◽

Soil Moisture Dynamics ◽

Moisture Dynamics

Abstract. Distributed and continuous catchment models are used to simulate water and energy balance and fluxes across varied topography and landscape. The landscape is discretized into plan computational elements at resolutions of 101–103 m, and soil moisture is the hydrologic state variable. At the local scale, the vertical soil moisture dynamics link hydrologic fluxes and provide continuity in time. In catchment models these local scale processes are modeled using one-dimensional soil columns that are discretized into layers that are usually 10−3–10−1 m in thickness. This creates a mismatch between the horizontal and vertical scales. For applications across large domains and in ensemble mode, this treatment can be a limiting factor due to its high computational demand. This study compares continuous multi-year simulations of soil moisture at the local scale using (i) a 1-D version of a distributed catchment hydrologic model; and (ii) a benchmark detailed soil water physics solver. The distributed model uses a single soil layer with a novel dual-pore structure, and employs linear parameterization of infiltration and some other fluxes. The detailed solver uses multiple soil layers and employs nonlinear soil physics relations to model flow in unsaturated soils. Using two sites with different climates (semiarid and sub-humid), it is shown that the efficient parameterization in the distributed model captures the essential dynamics of the detailed solver.

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Simplified stochastic soil moisture models: a look at infiltration

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-3-1339-2006 ◽

2006 ◽

Vol 3 (4) ◽

pp. 1339-1367 ◽

Cited By ~ 2

Author(s):

J. Rigby ◽

A. Porporato

Keyword(s):

Soil Moisture ◽

Time Scale ◽

Rectangular Pulse ◽

Short Time Scale ◽

Soil Moisture Dynamics ◽

Physically Based ◽

Rainfall Model ◽

Averaged Model ◽

Moisture Dynamics ◽

Daily Time

Abstract. A simplified, vertically averaged model of soil moisture interpreted at the daily time scale and forced by a stochastic process of instantaneous rainfall events is compared with a model which uses a non-overlapping rectangular pulse rainfall model and a more physically based description of infiltration. The models are compared with respect to the importance of short time-scale (intra-storm) variable infiltration in determining soil moisture dynamics at the daily time-scale. Differences in approach to infiltration modelling show only minor effects on the probabilistic structure of soil moisture dynamics as simulated in the two models. Examining closely the partitioning of losses during a rainfall event reveals that losses to percolation are significantly greater than that of Hortonian runoff. A possible improvement of the instantaneous rainfall model to incorporate a jump distribution with a state dependent mean is also discussed.

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