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Journal Article

Comparison of Hydraulic Conductivity in Frozen Saturated and Unfrozen Unsaturated Soils Available to Purchase

Kunio Watanabe, Yurie Osada
Published: 01 May 2016
Vadose Zone Journal (2016) 15 (5): vzj2015.11.0154.
DOI: https://doi.org/10.2136/vzj2015.11.0154
... conductivity of frozen soils has been limited. Therefore, it is often estimated from the unsaturated hydraulic conductivity of unfrozen soil using temperature and the Clausius–Clapeyron equation, with inadequate validation. In this study, we simultaneously measured the unfrozen water content and hydraulic...
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View PDF for article title, Comparison of Hydraulic Conductivity in Frozen Saturated and <span class="search-highlight">Unfrozen</span> Unsaturated <span class="search-highlight">Soils</span>
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Journal Article

Constitutive Model for Unfrozen Water Content in Subfreezing Unsaturated Soils Available to Purchase

Scott L. Painter, Satish Karra
Published: 01 April 2014
Vadose Zone Journal (2014) 13 (4): vzj2013.04.0071.
DOI: https://doi.org/10.2136/vzj2013.04.0071
... for flow in freezing soil. The results based on this modified Richards equation are shown to compare well with data from two different column experiments. * Corresponding author ( [email protected] ). 16 04 2013 Equation [3] relates the unfrozen water fraction to temperature...
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View PDF for article title, Constitutive Model for <span class="search-highlight">Unfrozen</span> Water Content in Subfreezing Unsaturated <span class="search-highlight">Soils</span>
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Journal Article

Determining Hydraulic Conductivity for Air-Filled Porosity in an Unsaturated Frozen Soil by the Multistep Outflow Method Available to Purchase

Ying Zhao, Taku Nishimura, Robert Hill, Tsuyoshi Miyazaki
Published: 01 February 2013
Vadose Zone Journal (2013) 12 (1): vzj2012.0061.
DOI: https://doi.org/10.2136/vzj2012.0061
... method using antifreeze liquid. Comparisons of water flow in both partially frozen and unfrozen soils indicated that frozen soil significantly reduced K ( h ) due to the blocking effects of ice crystals. Based on one common K ( h )-based hydraulic equation, an impedance parameter for liquid-filled...
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View PDF for article title, Determining Hydraulic Conductivity for Air-Filled Porosity in an Unsaturated Frozen <span class="search-highlight">Soil</span> by the Multistep Outflow Method
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(a) Soil thermal conductivity curves and (b) soil heat capacity curves of the 5-cm soil depth for the site that has been ungrazed since 1999(UG99) and for the site that has been grazed in the winter (WG). Black boxes (UG99) and red circles (WG) showed measured values with standard deviations in the unfrozen soil (filled symbols) and the frozen soil (open symbols). The measured data of soil thermal conductivity were fitted by Eq. [9] for unfrozen soil (solid lines) and frozen soil (dashed lines). The calculated curves of soil heat capacity are shown for unfrozen soil (solid lines) and frozen soil with an assumed 5% ice water content (dashed lines) for the UG99 site (black) and for the WG site (red).

(a) Soil thermal conductivity curves and (b) soil heat capacity curves of t... Available to Purchase

Published: 01 February 2013
deviations in the unfrozen soil (filled symbols) and the frozen soil (open symbols). The measured data of soil thermal conductivity were fitted by Eq. [9] for unfrozen soil (solid lines) and frozen soil (dashed lines). The calculated curves of soil heat capacity are shown for unfrozen soil (solid lines
Journal Article

Application of Multiphase Dielectric Mixing Models for Understanding the Effective Dielectric Permittivity of Frozen Soils Available to Purchase

Hailong He, Miles Dyck
Published: 01 February 2013
Vadose Zone Journal (2013) 12 (1): vzj2012.0060.
DOI: https://doi.org/10.2136/vzj2012.0060
... with respect to each other. The objective of this study was to improve understanding of some of the factors affecting the effective permittivity of frozen soils through the use of dielectric mixing models. Published datasets and frozen and unfrozen soil data measured on western Canadian soils were investigated...
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Journal Article

Water Infiltration into a Frozen Soil with Simultaneous Melting of the Frozen Layer Available to Purchase

Kunio Watanabe, Tetsuya Kito, Shuhui Dun, Joan Q. Wu, R. Cory Greer, Markus Flury
Published: 01 February 2013
Vadose Zone Journal (2013) 12 (1): vzj2011.0188.
DOI: https://doi.org/10.2136/vzj2011.0188
... at the beginning, (ii) slow infiltration as the infiltration front advanced through the frozen layer, and (iii) increased infiltration as the infiltration front advanced through the unfrozen soil below the frozen layer. The duration of each phase became longer with increasing initial soil water content...
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View PDF for article title, Water Infiltration into a Frozen <span class="search-highlight">Soil</span> with Simultaneous Melting of the Frozen Layer
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Journal Article

Determining Soil Ice Contents during Freezing and Thawing with Thermo-Time Domain Reflectometry Available to Purchase

Zhengchao Tian, Joshua Heitman, Robert Horton, Tusheng Ren
Published: 01 August 2015
Vadose Zone Journal (2015) 14 (8): vzj2014.12.0179.
DOI: https://doi.org/10.2136/vzj2014.12.0179
...Zhengchao Tian; Joshua Heitman; Robert Horton; Tusheng Ren Abstract Determining soil ice content during freezing and thawing is important and challenging for both engineering and environmental issues. The thermo-time domain reflectometry (T-TDR) probe, which can monitor unfrozen soil water content...
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Journal Article

Degrading permafrost mapped with electrical resistivity tomography, airborne imagery and LiDAR, and seasonal thaw measurements Available to Purchase

Thomas A. Douglas, M. Torre Jorgenson, Dana R. N. Brown, Seth W. Campbell, Christopher A. Hiemstra, Stephanie P. Saari, Kevin Bjella, Anna K. Liljedahl
Journal: Geophysics
Published: 17 December 2015
Geophysics (2016) 81 (1): WA71–WA85.
DOI: https://doi.org/10.1190/geo2015-0149.1
... for frozen versus unfrozen material. There was no clear relationship between elapsed time since fire and permafrost extent at our sites. However, we have found that the transition zone boundaries between permafrost soils and unfrozen soils in the collapse-scar bogs at our sites had complex and unpredictable...
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Journal Article

Heave and Heaving Pressure in Freezing Soils: A Unifying Theory Available to Purchase

Pieter H. Groenevelt, Cameron D. Grant
Published: 01 February 2013
Vadose Zone Journal (2013) 12 (1): vzj2012.0051.
DOI: https://doi.org/10.2136/vzj2012.0051
... function of both the unfrozen soil below the frozen fringe and the soil layer at sub-zero temperature. Here we attempt to reconcile the differences between these two schools by focusing on a representative publication from each of them. From the Anderson school we focus on Konrad (1993) and from...
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Journal Article

Using Soil Freezing Characteristics to Model Multi-Season Soil Water Dynamics Available to Purchase

G. N. Flerchinger, M. S. Seyfried, S. P. Hardegree
Published: 01 November 2006
Vadose Zone Journal (2006) 5 (4): 1143–1153.
DOI: https://doi.org/10.2136/vzj2006.0025
... of soil temperature and liquid water content under frozen conditions enables in situ estimation of the SMC curve through its similarity to the SFC. We investigated the applicability of deducing the SMC curve from in situ measurements of the SFC for simulation of both frozen and unfrozen soil water...
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View PDF for article title, Using <span class="search-highlight">Soil</span> Freezing Characteristics to Model Multi-Season <span class="search-highlight">Soil</span> Water Dynamics
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Book Chapter

Effects of weather and soil characteristics on temporal variations in soil-gas radon concentrations Available to Purchase

Author(s)
R. Randall Schumann, Douglass E. Owen, Sigrid Asher-Bolinder
Book: Geologic Controls on Radon
Publisher: Geological Society of America
Published: 01 January 1992
DOI: 10.1130/SPE271-p65
... and removal of radon from the soil. A capping effect caused by frozen or unfrozen soil moisture is a primary mechanism for preventing radon loss to the atmosphere. ...
Abstract
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Concentrations of radon-222 in soil gas measured over about 1 yr at a monitoring site in Denver, Colorado, vary by as much as an order of magnitude seasonally and as much as severalfold in response to changes in weather. The primary weather factors that influence soil-gas radon concentrations are precipitation and barometric pressure. Soil characteristics are important in determining the magnitude and extent of the soil’s response to weather changes. The soil at the study site is clay rich and develops desiccation cracks upon drying that increase the soil’s permeability and enhance gas transport and removal of radon from the soil. A capping effect caused by frozen or unfrozen soil moisture is a primary mechanism for preventing radon loss to the atmosphere.

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Schematic illustration of soil pore distribution g(r) and corresponding impedance factor (Ω) or apparent impedance factor (Ωa) for unfrozen and frozen soil utilized for (a) water hydraulic conductivity K(h) at a matric potential of h = −600 hPa in unfrozen soil, (b) relative pore size occupied at −10°C by ice and unfrozen water hydraulic conductivity Kf(h) at a matric potential of h = −12 MPa, and (c) relative pore size occupied at −10°C by ice and antifreeze solution and antifreeze hydraulic conductivity Kaf(h).

Schematic illustration of soil pore distribution g ( r ) and corresponding... Available to Purchase

Published: 01 February 2013
Fig. 2. Schematic illustration of soil pore distribution g ( r ) and corresponding impedance factor (Ω) or apparent impedance factor (Ω a ) for unfrozen and frozen soil utilized for (a) water hydraulic conductivity K ( h ) at a matric potential of h = −600 hPa in unfrozen soil, (b) relative
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Relationship between hydraulic conductivity and liquid water content. Plots show observed data from frozen soils, and lines are the results of evaporation experiments for unfrozen soils.

Relationship between hydraulic conductivity and liquid water content. Plots... Available to Purchase

Published: 01 May 2016
Fig. 9. Relationship between hydraulic conductivity and liquid water content. Plots show observed data from frozen soils, and lines are the results of evaporation experiments for unfrozen soils.
Image
Unfrozen data from six western Canadian soils with discrete and confocal models for constant water permittivity (see Table 3 for the parameters and goodness of fit).

Unfrozen data from six western Canadian soils with discrete and confocal mo... Available to Purchase

Published: 01 February 2013
Fig. 9. Unfrozen data from six western Canadian soils with discrete and confocal models for constant water permittivity (see Table 3 for the parameters and goodness of fit).
Image
Measured cumulative outflow (circles), matric potential (squares), and simulated curves by the inverse method for the unfrozen soil. The arrows with number show the values of the applied air pressure.

Measured cumulative outflow (circles), matric potential (squares), and simu... Available to Purchase

Published: 01 February 2013
Fig. 4. Measured cumulative outflow (circles), matric potential (squares), and simulated curves by the inverse method for the unfrozen soil. The arrows with number show the values of the applied air pressure.
Image
Measured thermal conductivity, λ0, of Kanagawa sandy loam soil (symbols) as a function of temperature and water content (Mizoguchi, 1990), as well as its parameterizations used in numerical simulations (lines) using Eq. [15]. The upper graph shows the thermal conductivity for frozen conditions at total volumetric water contents of 0.20, 0.30, and 0.40, and the lower graph the thermal conductivity of unfrozen soil at various water contents.

Measured thermal conductivity, λ 0 , of Kanagawa sandy loam soil (symbols) ... Available to Purchase

Published: 01 May 2004
for frozen conditions at total volumetric water contents of 0.20, 0.30, and 0.40, and the lower graph the thermal conductivity of unfrozen soil at various water contents.
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Relationship between hydraulic conductivity and temperature during thawing of (a) an Andisol at different water flow rates (Jw), and (b) silt loam and sand at a flow rate of 0.53 m d−1. The lines indicate the unsaturated hydraulic conductivity of unfrozen soil (Kunfr; Fig. 1b), in which the matric potential was converted to the corresponding temperature using Eq. [1].

Relationship between hydraulic conductivity and temperature during thawing ... Available to Purchase

Published: 01 May 2016
Fig. 8. Relationship between hydraulic conductivity and temperature during thawing of (a) an Andisol at different water flow rates ( J w ), and (b) silt loam and sand at a flow rate of 0.53 m d −1 . The lines indicate the unsaturated hydraulic conductivity of unfrozen soil ( K unfr ; Fig. 1b
Image
GPR response in grounded ice conditions (data collected at 25  km/h). The quadruple material junction point is circled. The reflection from the ice/water interface, the ice/frozen-soil interface, and the frozen-soil/unfrozen-soil interface is annotated. The water-bottom reflection is seldom visible owing to the rapid increase in traveltime associated with the low EM wave velocity in water. (This event is usually beyond the GPR time-recording window in many cases.) The velocity of EM waves of 0.146  m/ns has been determined using local ice auger data.

GPR response in grounded ice conditions (data collected at 25     km... Available to Purchase

Published: 28 December 2015
Figure 7. GPR response in grounded ice conditions (data collected at 25     km / h ). The quadruple material junction point is circled. The reflection from the ice/water interface, the ice/frozen-soil interface, and the frozen-soil/unfrozen-soil interface is annotated. The water
Image
(a) Schematic diagram showing how new ice lenses can nucleate off the side of shrinkage cracks that grow into the soil ahead of an existing ice lens, from Style et al., 2011; and (b) a freezing block of Devon silt that is broken open at the freezing front, from Arenson et al., 2008. The left-hand block is the upper, frozen soil. The right-hand block is the warmer, unfrozen soil. A polygonal network of shrinkage cracks can clearly be seen extending out of the frozen material. The sample diameter is about 100 mm.

(a) Schematic diagram showing how new ice lenses can nucleate off the side ... Available to Purchase

Published: 01 February 2013
. The left-hand block is the upper, frozen soil. The right-hand block is the warmer, unfrozen soil. A polygonal network of shrinkage cracks can clearly be seen extending out of the frozen material. The sample diameter is about 100 mm.
Journal Article

Ground-penetrating radar for assessing winter roads Available to Purchase

A. Peter Annan, Nectaria Diamanti, J. David Redman, Steven R. Jackson
Journal: Geophysics
Published: 28 December 2015
Geophysics (2016) 81 (1): WA101–WA109.
DOI: https://doi.org/10.1190/geo2015-0138.1
...Figure 7. GPR response in grounded ice conditions (data collected at 25     km / h ). The quadruple material junction point is circled. The reflection from the ice/water interface, the ice/frozen-soil interface, and the frozen-soil/unfrozen-soil interface is annotated. The water...
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