Publications

Journal: Hydrological Processes

DOI: https://doi.org/10.1002/hyp.14056 

Abstract: River supercooling and ice formation is a regular occurrence throughout the winter in northern countries. The resulting frazil ice production can obstruct the flow through intakes along the river, causing major problems for hydropower and water treatment facilities, among others. Therefore, river ice modellers attempt to calculate the river energy budget and predict when supercooling will occur in order to anticipate and mitigate the effects of potential intake blockages. Despite this, very few energy budget studies have taken place during freeze-up, and none have specifically analysed individual supercooling events. To improve our understanding of the freeze-up energy budget detailed measurements of air temperature, relative humidity, barometric pressure, wind speed and direction, short- and longwave radiation, and water temperature were made on the Dauphin River in Manitoba. During the river freeze-up period of late October to early November 2019, a total of six supercooling events were recorded. Analysis of the energy budget throughout the supercooling period revealed that the most significant heat source was net shortwave radiation, reaching up to 298 W/m2, while the most significant heat loss was net longwave radiation, accounting for losses of up to 135 W/m2. Longwave radiation was also the most significant heat flux overall during the individual supercooling events, accounting for up to 84% of the total heat flux irrespective of flux direction, highlighting the importance of properly quantifying this flux during energy budget calculations. Five different sensible (Qh) and latent (Qe) heat flux calculations were also compared, using the bulk aerodynamic method as the baseline. It was found that the Priestley and Taylor method most-closely matched the bulk aerodynamic method on a daily timescale with an average offset of 8.5 W/m2 for Qh and 10.1 W/m2 for Qe, while a Dalton-type equation provided by Webb and Zhang was the most similar on a sub-daily timescale with average offsets of 20.0 and 14.7 W/m2 for Qh and Qe, respectively. 

Journal: Cold Regions Science and Technology

DOI: https://doi.org/10.1016/j.coldregions.2019.102812 

Abstract: Field images of in-situ frazil ice particles captured using a submersible camera system called the FrazilCam have proven difficult to analyse due to the presence of suspended sediment particles. McFarlane et al. (2017) accounted for this by subtracting an appropriately-scaled sediment size distribution from the overall size distribution, resulting in an estimate of the size distribution of frazil ice particles. However, this method over-compensated for the effect of suspended sediment particles and completely eliminated certain portions of the size distribution representing ice particles with diameters on the order of ~0.1 mm. In order to process FrazilCam images with greater accuracy, a machine learning algorithm has been trained to classify each individual particle as ice or sediment during image processing, resulting in more accurate size distributions of the frazil ice particles. The methodology used to train and validate the machine learning algorithm is described, and the data previously presented by McFarlane et al. (2017) are reanalysed. This resulted in a decrease in the mean diameters for each deployment reported by McFarlane et al. (2017); however, the overall trends reported remained the same. 

Journal: Cold Regions Science and Technology

DOI: https://doi.org/10.1016/j.coldregions.2019.102796 

Abstract: The FrazilCam system, developed to photograph suspended frazil ice crystals in field environments, was deployed in the Kananaskis, North Saskatchewan, and Peace Rivers in Alberta. Images captured during each deployment were processed and analysed using a support vector machine (SVM) learning algorithm to separate fine suspended sediment particles that were visible in the images from the suspended frazil crystals. The size distribution of the frazil ice crystals was then produced and found to be well described by a lognormal distribution in almost all cases where the flow rate remained constant. The mean particle diameter ranged from 0.32 to 1.32 mm and volume concentrations ranging from 1.0 to 15 × 10−6 m3/m3 were calculated by assuming a constant diameter to thickness ratio of 37 for the frazil ice discs. Additionally, a unique supercooling event that reached the extremely low temperature of −0.15 °C was observed in the North Saskatchewan River and resulted in the growth of long, shard-like anchor ice crystals on all objects submerged in the flow. 

Journal: Cold Regions Science and Technology

DOI: https://doi.org/10.1016/j.coldregions.2017.08.001 

Abstract: The size distribution of frazil ice particles has been studied extensively in laboratory environments but has proven much more difficult to measure in rivers. To make accurate measurements of frazil ice particle sizes and shapes in rivers, a novel submersible imaging system, called the FrazilCam, was designed and custom-built. The FrazilCam consists of a Nikon D800 digital single-lens reflex (DSLR) camera contained in a waterproof housing and programmed to capture images of frazil ice particles as they pass between two glass cross-polarising filters. Throughout the winter of 2014–15, the FrazilCam was deployed a total of six times in three different Alberta streams: the North Saskatchewan River at Edmonton, the Peace River at Fairview, and the Kananaskis River near Kananaskis Village. The resulting images were processed using a MATLAB algorithm and the size distribution of the suspended particles was determined. These are the first quantitative measurements of frazil ice size distributions made in rivers. It was observed that the mean particle diameter was larger during the principal supercooling stage, ranging from 0.73 to 1.20 mm, and reached a smaller mean diameter during the residual supercooling phase, with mean diameters ranging from 0.32 to 0.61 mm observed. Each of the frazil ice size distributions was reasonably well described by a lognormal distribution, which has long been used to describe the distribution of frazil particles produced in laboratory settings but never before been confirmed in the field. 

Journal: Cold Regions Science and Technology

DOI: https://doi.org/10.1016/j.coldregions.2017.09.003 

Abstract: The impact of sediment transport by anchor ice release on the annual sediment budgets of rivers is unknown. Sediment transport on regulated rivers could be significant since open water persists throughout the winter season and anchor ice forms and releases often. Studies that quantify the amount of sediment carried or rafted by released anchor ice pans are rare and have been performed on unregulated rivers with significantly different flow regimes, or have few collected samples. In this study, anchor ice samples were collected on three regulated rivers in Alberta: the North Saskatchewan, Peace and Kananaskis River. Previous studies on the amount of sediment contained in anchor ice are discussed and compared. Gravel and cobble sized particles were also sampled from anchor ice pans as they floated by to better understand the largest sediment anchor ice transports. The sampled gravels and cobbles contained in anchor ice showed that 24% of the total sampled mass came from only 1.2% of the particles sampled. The average sediment concentration contained in released, floating anchor ice was found to be 28.2 g/L, with a standard deviation of 33.2 g/L, and a median of 18.4 g/L. This information will allow for more accurate estimations of how transport of sediment by anchor ice releases affects the annual sediment budget on regulated rivers. 

Journal: Cold Regions Science and Technology

DOI: https://doi.org/10.1016/j.coldregions.2015.09.001 

Abstract: A series of 27 experiments were carried out at three different turbulence intensities in the frazil ice production tank at the University of Alberta. The frazil particles produced were photographed in suspension throughout the duration of the supercooling process using a high-resolution digital camera. An acoustic Doppler velocimeter (ADV) was used to record vertical profiles of the velocities at three locations in the tank, and the velocity time series data were processed to determine the rate of dissipation of turbulent kinetic energy per unit mass. A computer algorithm was written to process the captured images to determine the particle sizes and compute the properties of the particle size distribution. The resulting data were used to study the evolution of the size distribution throughout the supercooling process. It was found that the number of individual particles in suspension peaked shortly after the maximum degree of supercooling had been reached, and at approximately the same time the mean and standard deviation of the particle diameter approached constant values. The overall mean particle diameter prior to the onset of particle flocculation was found to decrease with increasing values of the dissipation rate, and ranged from 0.94 to 0.66 mm for dissipation rates of 24 to 336 cm2/s3. 

Journal: Cold Regions Science and Technology

DOI: https://doi.org/10.1016/j.coldregions.2014.06.009

Abstract: The rise velocity of frazil ice particles has proven difficult to measure with any accuracy. As a result the physics of rising frazil ice particles are poorly understood, making it difficult to determine whether skim ice, frazil ice, or both will be present during the early stages of river freeze-up. Past experimental studies have observed particles rising at a wide range of velocities, but without precise measurements of the particle diameter no definitive relationships could be determined. In this study, high-resolution digital images were taken of rising frazil ice particles as they passed between two cross-polarising filters. An image processing algorithm was used to accurately calculate the diameter of each rising particle and the movement of its centroid was then tracked through a series of images to determine the rise velocity based on the total vertical displacement. Rise velocities ranging from 0.40 to 13.47 mm/s for particles with diameters in the range of 0.24 to 3.35 mm were observed. Existing theoretical solutions for the rise of a horizontal disc were compared to the measured data and a new function relating the rise velocity to the diameter of a vertically oriented rising disc was derived. It was found that all of the data could be enveloped by curves corresponding to a vertical disc with an aspect ratio of 10 and a horizontal disc with an aspect ratio of 80. In some cases, the thickness of a particle could also be estimated from the images and thicknesses ranging from 0.03 to 0.12 mm with a mean of 0.07 mm were observed with aspect ratios in the range of 11 to 71. Based on this information it is suggested that the assumption of discs having a constant aspect ratio is inaccurate. 

A tool for estimating consequence classification of small dams in an urban setting
Top 5 Finalist in the Outstanding YP Paper Competition
McFarlane, V., Ghavasieh, R., and Pokhrel, N. (2024)
United States Society on Dams (USSD)
Proceedings of the USSD 2024 Annual Conference

Use of NASA CERES Satellite Data to Calculate the Net Heat Flux of the Dauphin River During Supercooling
Accompanied by Oral Presentation
McFarlane, V., Lim, K., and Clark, S. P. (2023)
CGU-HS Committee on River Ice Processes and the Environment (CRIPE)
Proceedings of the 22nd Workshop on the Hydraulics of Ice-Covered Rivers

In-situ measurements of anchor-ice formation and release
Ghobrial, T. R., McFarlane, V., and Loewen, M. R. (2019)
CGU-HS Committee on River Ice Processes and the Environment (CRIPE)
Proceedings of the 20th Workshop on the Hydraulics of Ice-Covered Rivers

Field Measurements of Supercooling in the North Saskatchewan River
Kalke, H., McFarlane, V., Ghobrial, T. R., and Loewen, M. R. (2019)
CGU-HS Committee on River Ice Processes and the Environment (CRIPE)
Proceedings of the 20th Workshop on the Hydraulics of Ice-Covered Rivers

Laboratory measurements of frazil ice properties in saline water
Schneck, C., McFarlane, V., and Loewen, M. (2017)
CGU-HS Committee on River Ice Processes and the Environment (CRIPE)
Proceedings of the 19th Workshop on the Hydraulics of Ice-Covered Rivers

Field observations of the growth rate of anchor ice crystals
Accompanied by Oral Presentation
McFarlane, V., Loewen, M., and Hicks, F. (2016)
International Association for Hydro-Environment Engineering and Research (IAHR)
Proceedings of the 23rd IAHR International Symposium on Ice

Ice rafting of sediment by anchor ice releases
Kalke, H., Loewen, M., McFarlane, V., and Jasek, M. (2015)
International Association for Hydro-Environment Engineering and Research (IAHR)
Proceedings of the 23rd IAHR International Symposium on Ice

Field measurements of the size distribution of frazil ice particles
Accompanied by Oral Presentation
McFarlane, V., Loewen, M., and Hicks, F. (2015)
CGU-HS Committee on River Ice Processes and the Environment (CRIPE)
Proceedings of the 18th Workshop on the Hydraulics of Ice-Covered Rivers

Observations of anchor ice formation and rafting of sediments
Kalke, H., Loewen, M., McFarlane, V., and Jasek, M. (2015)
CGU-HS Committee on River Ice Processes and the Environment (CRIPE)
Proceedings of the 18th Workshop on the Hydraulics of Ice-Covered Rivers

Effects of turbulence intensity on frazil ice particle characteristics
Recipient of the Best Student Paper Prize
Accompanied by Oral Presentation
McFarlane, V., Loewen, M., and Hicks, F. (2014)
International Association for Hydro-Environment Engineering and Research (IAHR)
Proceedings of the 22nd IAHR International Symposium on Ice

Laboratory measurements of frazil ice rise velocity
Recipient of the Best Student Paper Award
Accompanied by Oral Presentation
McFarlane, V., Loewen, M., and Hicks, F. (2013)
CGU-HS Committee on River Ice Processes and the Environment (CRIPE)
Proceedings of the 17th Workshop on River Ice

Measuring supercooling prevalence on small regulated and unregulated streams in New Brunswick and Newfoundland, Canada
Recipient of the R. Larry Gerard Medal as the best paper at the conference
Nafziger, J., Hicks, F., Thoms, P., McFarlane, V., Banack, J., and Cunjack, R. A. (2013)
CGU-HS Committee on River Ice Processes and the Environment (CRIPE)
Proceedings of the 17th Workshop on River Ice

Laboratory experiments to determine frazil ice properties
Accompanied by Oral Presentation
McFarlane, V., Loewen, M., and Hicks, F. (2012)
Canadian Society for Civil Engineering (CSCE)
Proceedings of the Annual Conference and General Meeting of the CSCE - 2012

Posters

Winter ice processes of the Kananaskis River, Alberta
Recipient of the Best Student Poster Award
Emmer, S., Nafziger, J., McFarlane, V., Loewen, M., and Hicks, F. (2013)
CGU-HS Committee on River Ice Processes and the Environment (CRIPE)
Proceedings of the 17th Workshop on River Ice

Presentations

Measurements of frazil ice particles at the onset of supercooling
McFarlane, V., Loewen, M., and Hicks, F. (2017)
CGU-HS Committee on River Ice Processes and the Environment (CRIPE)
Proceedings of the 19th Workshop on the Hydraulics of Ice-Covered Rivers

Laboratory and Field Measurements of Frazil Ice Characteristics
Ph.D. Thesis
https://doi.org/10.7939/r3-pwv3-nf92 

Laboratory Studies of Suspended Frazil Ice Particles
M.Sc. Thesis
https://doi.org/10.7939/R3X921S6Q 

Comparison of Empirical Equations for Dam Breach Outflow when Applied to Small Dams
Yassin, M., and McFarlane, V. (2023)
Research Report 

River freeze-up: Properties of freshwater frazil ice particles
Presentation, 2018
Presented to the Physical Oceanography group, Department of Earth Sciences, University of Oxford

Frozen Kaleidoscope
Photograph, 2017
Semi-finalist Prize, University of Alberta Images of Research Competition 2017
https://doi.org/10.7939/R3T43JG35