Ice jam release surges, ice runs, and breaking fronts: field measurements, physical descriptions, and research needs

2003 ◽  
Vol 30 (1) ◽  
pp. 113-127 ◽  
Author(s):  
Martin Jasek
Keyword(s):  
Unsteady Flow ◽  
Field Measurements ◽  
Open Water ◽  
Two Phase ◽  
Ice Jams ◽  
Water Ice ◽  
Flow Models ◽  
Ice Jam ◽  
Recent Developments ◽  
Break Up

Surges or flood waves made up of ice and water resulting from the release of ice jams can be destructive to life and property and are also one of the more complicated problems in river ice engineering. The interaction between the ice mechanics and unsteady flow leads to results that are often unpredictable with open water unsteady flow models. There are considerable differences of opinion on the degree of significance of this water–ice interaction. There have also been recent developments in two-phase unsteady flow modelling which are capable of handling these complicated situations. It is the aim of this paper to present both quantitative data and qualitative observations on ice runs and breaking fronts to provide insight to the physical processes involved as and possible sources of model calibration data.Key words: ice jam, surge, unsteady flow, ice run, ice jam release, breaking front, break-up, breakup, break-up front.

Ice jams in shallow rivers with floodplain flow

1983 ◽  
Vol 10 (3) ◽  
pp. 538-548 ◽  
Author(s):  
Darryl J. Calkins
Keyword(s):  
Field Measurements ◽  
Close Correlation ◽  
Ice Cover ◽  
Ice Jams ◽  
Ice Jam ◽  
Surface Gradient ◽  
Breakup Channel ◽  
Modified Equations ◽  
Cover Thickness ◽  
Ice Jam Thickness

The equilibrium ice jam thickness given by Pariset et al. is modified to yield a clearer, consistent relationship between the flow hydraulics and thickness. The modified equations are analyzed with respect to a floating ice jam in the main channel with flow also occurring in the floodplain. The final derivation allows the expected ice jam thickness to be computed, given the bed and ice cover roughness coefficients, the channel characteristics, the water surface gradient, and the pre-breakup channel ice cover thickness. The analytical computation for the ice jam thicknesses is compared with prototype data on ice jam thicknesses from four shallow rivers which had significant floodplain flow with the ice jam event. A reasonable correlation between the predicted and measured ice jam thicknesses was obtained. The data suggests that once bankfull depth is exceeded the ice jam thickness does not increase appreciably because of flow diversion to the floodplain. Field measurements of the thickness of the remaining ice jam shear wall along with actual measurements of the ice jam thickness showed a close correlation between the two sets of data.

High-accuracy mapping of inundations induced by ice jams: a case study from Iceland

2012 ◽  
Vol 43 (4) ◽  
pp. 412-421 ◽  
Author(s):  
Emmanuel Pagneux ◽  
Árni Snorrason
Keyword(s):  
Flood Hazard ◽  
Numerical Models ◽  
Open Water ◽  
Flood Hazards ◽  
Hydraulic Modelling ◽  
Photo Interpretation ◽  
Ice Jams ◽  
Ice Jam ◽  
Digital Elevation ◽  
Elevation Model

Hydraulic modelling is widely used for deriving flood hazard maps featuring depth of flooding and flow velocity from discharge scenarios. Due to uncertainties about flow conditions or inaccurate terrain models, flood hazards maps obtained from hydraulic modelling may be of limited relevance and accuracy. Hydraulic modelling is particularly challenging in Arctic regions, where ice jams lead to flooding in areas that would not be subjected to inundation under open-water conditions. As numerical models of ice jam processes require information that may be difficult and expensive to collect, an alternative approach based on the photo interpretation of documented historical events is presented here. Orthophotographs and a digital elevation model at high resolution are used to support the photo interpretation process. Tested in an Icelandic watershed prone to ice jam floods, reconstructions provide locally unprecedented and robust information on the extent and depth of flooding of inundations induced by ice jams.

scholarly journals River predisposition to ice jams: a simplified geospatial model

2016 ◽  
Author(s):  
Stéphane De Munck ◽  
Yves Gauthier ◽  
Monique Bernier ◽  
Karem Chokmani ◽  
Serge Légaré
Keyword(s):  
Local Knowledge ◽  
False Positive ◽  
False Negative ◽  
River Channel ◽  
Geospatial Data ◽  
River Ice ◽  
Main Question ◽  
Ice Jams ◽  
Ice Jam ◽  
Break Up

Abstract. The goal of this work was to develop a simplified geospatial model to estimate the predisposition of any river channel to ice jams. Rather than predicting river ice break up, the main question here was to predict where the broken up ice is susceptible to jam based on the river’s geomorphological characteristics. Thus, six parameters referred to potential causes for ice jams in the literature were selected: presence of an island, narrowing of the channel, high sinuosity, presence of a bridge, confluence of rivers, and slope break. A GIS-based tool has been used to generate the aforementioned factors over regular-spaced segments along the entire channel using available geospatial data. An "Ice Jam Predisposition Index" (IJPI) was calculated by combining the weighted optimal factors. Three Canadian rivers (Province of Quebec) have been chosen as test sites. The resulting maps were assessed from historical observations and local knowledge. Results show 77 % of the observed ice jam sites on record occurred in river sections that the model considered as having high or medium predisposition. This leaves 23 % of false negative errors (missed occurrence). Between 7 % and 11 % of the highly "predisposed" river sections did not have an ice jam on record (false-positive errors). Potential improvements are discussed.

Analysis of breakup and ice jams on the Athabasca River at Fort McMurray, Alberta

1984 ◽  
Vol 11 (3) ◽  
pp. 444-458 ◽  
Author(s):  
D. D. Andres ◽  
P. F. Doyle
Keyword(s):  
Internal Friction ◽  
Open Water ◽  
Water Levels ◽  
Roughness Coefficient ◽  
Produce Water ◽  
Ice Jams ◽  
Athabasca River ◽  
Fort Mcmurray ◽  
Ice Jam ◽  
Clearwater River

During breakup, severe ice jams form at Fort McMurray, Alberta because of the dramatic change in the character of the Athabasca River at that location. Such jams, which produce water levels in the order of 10 m above the normal open water stage, were documented in 1977, 1978, and 1979. Additional channel surveys and improved estimates of discharge made since the initial analysis have redefined the ice jam characteristics. The Manning roughness coefficient of the underside of the ice jams was found to be 0.072. The new discharge estimates, which were up to twice those previously reported, result in a calculated coefficient of internal friction of 0.8–2.7. This is 30–100% greater than previous estimates, but still similar to values determined for ice jams at other locations.Even with the variation in the coefficient of internal friction, the river stage due to an ice jam at Fort McMurray could be computed with reasonable accuracy for a range of given discharges. If jams form downstream of the mouth of the Clearwater River at discharges greater than 800 m3/s (considerably less than the 1-in-2-year open water flood), flooding will occur within lower Fort McMurray. Unfortunately, the frequency of such an event is unknown because the probabilities of both the discharge being exceeded and the jam occurrence cannot be defined. Key words: ice, breakup, ice jam, ice roughness, flooding, hydraulics.

Thermal budget of river ice covers during breakup

1989 ◽  
Vol 16 (1) ◽  
pp. 62-71 ◽  
Author(s):  
T. D. Prowse ◽  
P. Marsh
Keyword(s):  
Heat Input ◽  
Leading Edge ◽  
Field Measurements ◽  
Open Water ◽  
Heat Fluxes ◽  
River Ice ◽  
Ice Jams ◽  
Frazil Ice ◽  
Ice Melt ◽  
Ice Roughness

The magnitude and relative importance of atmosheric (air–ice) and hydrothermal (water–ice) heat fluxes to intact and fragmented river ice covers are studied for the case of a thermal breakup. Based on field measurements obtained from the Liard River, the atmospheric sources are shown to be dominant during the period of intact ice cover. Radiation was the primary heat source, but its effect was reduced by a granulation of the decaying columnar ice which increased the cover albedo to that comparable for melting snow. The hydrothermal heat input, even with frazil ice entrained within the flow, was comparable to that from atmospheric sources under low melt conditions. The hydrothermal heat flux dramatically increased with the arrival of the breakup front because of a rapid rise in water temperature and an increase in subsurface ice roughness. Higher surface roughness and lower albedo of the fragmented ice also increased the atmospheric heat fluxes, but these were small relative to the hydrothermal heat input near the leading edge of open water. Key words: floating ice, ice breakup, ice jams, ice melt.

scholarly journals Freeze-Up Ice Jam Formation in the River Bend, a Case Study on the Inner Mongolia Reach of Yellow River

Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 631
Author(s):  
Shui-Xia Zhao ◽  
Wen-Jun Wang ◽  
Xiao-Hong Shi ◽  
Sheng-Nan Zhao ◽  
Ying-Jie Wu ◽  
...  
Keyword(s):  
Sediment Transport ◽  
Yellow River ◽  
Open Water ◽  
River Ice ◽  
Freezing Process ◽  
Ice Jams ◽  
Narrow Channels ◽  
Frazil Ice ◽  
Ice Jam ◽  
Bed Changes

Concern has been expressed regarding the impacts of climate change on river ice and ice jam formation in cold regions. Ice jams are easily initiated in bends and narrow channels and cause disasters. In this study, observations and remote sensing monitoring are used to study the freeze-up ice jam formation of bends. Sediment transport and freezing process of the river interact, influencing bed changes profile and sedimentary budget. River ice processes, channel evolution, ice hydro-thermodynamics, and ice jam accumulation are explored. The results show that the channel topography determines the river thalweg, and that the channel elevation interacts with the river ice through sediment transport. The channel shrinkage increases the probability of ice jam, and the sharp bend is prone to ice jam formation. Under the effect of secondary circulation flow in the bend and in the outer bank, the juxtaposed freeze-up and the hummocky ice cover occur in the same location, and frazil ice accumulates under the junction of the main channel and the shoals. Affected by the increase of the hydraulic slope and the velocity downstream, open water reaches develops downstream of the ice accumulation. An open water section is emerged upstream of the bend, due to the ice deposition, and partly cut-off supply of the frazil.

Review of prediction methods for breakup ice jams

2003 ◽  
Vol 30 (1) ◽  
pp. 89-100 ◽  
Author(s):  
Kathleen D White
Keyword(s):  
Open Water ◽  
Flood Damage ◽  
Water Levels ◽  
Water Flooding ◽  
Prediction Methods ◽  
Deterministic Models ◽  
Flood Prediction ◽  
Ice Jams ◽  
Ice Jam ◽  
Flood Warning

Breakup ice jams often occur suddenly, with little warning. Severe flooding or ice-related damage can result from rapid rises in upstream water levels associated with breakup ice jams. Breakup jam prediction methods that can be used to increase response time are desirable to minimize flood damage, including potential loss of life. A variety of hydrologic and hydraulic models exist to predict open-water flooding, whether resulting from rainfall, snowmelt, or catastrophic events such as dam breaches. However, breakup ice jams result from a complex series of physical processes that cannot currently be described with analytical or deterministic models, hindering the development of prediction methods. Those which do exist are highly site specific and range from simple empirical models to an artificial intelligence formulation. To date, no one model exhibits a clear advantage over the others. This paper provides examples of existing breakup ice jam prediction methods and discusses their potential advantages and disadvantages.Key words: ice jam, breakup ice jam, flood prediction, flood warning, ice jam mitigation.

Recent Developments in Computational Methods for the Analysis of Ducted Propellers in Open Water

2019 ◽  
Vol 63 (4) ◽  
pp. 219-234
Author(s):  
João Baltazar ◽  
José A. C. Falcão de Campos ◽  
Johan Bosschers ◽  
Douwe Rijpkema
Keyword(s):  
Computational Methods ◽  
Open Water ◽  
Boundary Element Methods ◽  
Navier Stokes ◽  
Hydrodynamic Analysis ◽  
Numerical Predictions ◽  
Ducted Propeller ◽  
Recent Developments ◽  
Propeller Performance ◽  
Ducted Propellers

This article presents an overview of the recent developments at Instituto Superior Técnico and Maritime Research Institute Netherlands in applying computational methods for the hydrodynamic analysis of ducted propellers. The developments focus on the propeller performance prediction in open water conditions using boundary element methods and Reynolds-averaged Navier-Stokes solvers. The article starts with an estimation of the numerical errors involved in both methods. Then, the different viscous mechanisms involved in the ducted propeller flow are discussed and numerical procedures for the potential flow solution proposed. Finally, the numerical predictions are compared with experimental measurements.

scholarly journals Port-Hamiltonian formulation of two-phase flow models

2021 ◽  
Vol 149 ◽  
pp. 104881
Author(s):  
H. Bansal ◽  
P. Schulze ◽  
M.H. Abbasi ◽  
H. Zwart ◽  
L. Iapichino ◽  
...  
Keyword(s):  
Two Phase Flow ◽  
Hamiltonian Formulation ◽  
Phase Flow ◽  
Two Phase ◽  
Flow Models
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