scholarly journals Analysis of river ice motion near a breaking front

1992 ◽  
Vol 19 (1) ◽  
pp. 105-116 ◽  
Author(s):  
M. G. Ferrick ◽  
P. B. Weyrick ◽  
S. T. Hunnewell
Keyword(s):  
Key Words ◽  
Surface Area ◽  
Ice Cover ◽  
Physical Characteristics ◽  
River Ice ◽  
Quantitative Theory ◽  
Ice Breakup ◽  
Essential Components ◽  
River Reach ◽  
Ice Velocity

Dynamic river ice breakup displays different behaviors depending on the physical characteristics of the river, the flow, and the ice cover. Although a quantitative theory of dynamic breakup is not yet available, one of the essential components of such a theory will be a description of the ice motion near the breaking front. In this paper we develop an analysis of this motion for a specific case. The analysis is generalized by allowing the speed of the breaking front to vary, and the parameters of the ice motion that are obtained represent different dynamic breakup behaviors that have been previously described. The results of the analysis include (i) the ice velocity, ice acceleration, and bank resistance at each point in a river reach as functions of time, (ii) the equilibrium ice velocity as a function of bank resistance and the ice velocity as a function of time for several initial and bank resistance conditions, and (iii) the time of ice motion, ice velocity, ice acceleration, and the convergence of the moving ice with distance from the breaking front. The measure of ice convergence quantifies the loss of surface area by the sheet required for ice continuity, and distinguishes the basic types of dynamic breakup. Key words: breaking front, dynamic ice breakup, ice continuity, ice convergence, ice motion, river ice.

Damage resulting from a sudden river ice breakup

1988 ◽  
Vol 15 (4) ◽  
pp. 609-615 ◽  
Author(s):  
P. F. Doyle
Keyword(s):  
Key Words ◽  
Sharp Increase ◽  
Private Property ◽  
Ice Cover ◽  
Flood Damage ◽  
River Ice ◽  
Public And Private ◽  
Ice Jams ◽  
Melting Snow ◽  
Ice Breakup

On January 4, 1984, the Nicola River and its two main tributaries broke up suddenly due to a sharp increase in discharge from a rain-on-melting-snow event while the ice cover was still thick and strong. The resulting ice run and attendant jamming caused hundreds of thousands of dollars in damage to public and private property, including the destruction of a bridge and several riprapped banks. Four ice jams remained in place for up to a week after the ice drive. All the damage was due either to the severe ice run within the channel or to flow forced out over the floodplain by ice jams. Key words: flood damage, ice run, ice breakup, ice jams, riprap.

Ice jam mitigation

1990 ◽  
Vol 17 (5) ◽  
pp. 675-685 ◽  
Author(s):  
Harold S. Belore ◽  
Brian C. Burrell ◽  
Spyros Beltaos
Keyword(s):  
Key Words ◽  
Carrying Capacity ◽  
Flood Control ◽  
Human Life ◽  
Water Levels ◽  
Economic Losses ◽  
River Ice ◽  
Ice Jams ◽  
Ice Jam ◽  
Ice Breakup

In Canada, flooding due to the rise in water levels upstream of an ice jam, or the temporary exceedance of the flow and ice-carrying capacity of a channel upon release of an ice jam, has resulted in the loss of human life and extensive economic losses. Ice jam mitigation is a component of river ice management which includes all activities carried out to prevent or remove ice jams, or to reduce the damages that may result from an ice jam event. This paper presents a brief overview of measures to mitigate the damaging effects of ice jams and contains a discussion on their application to Canadian rivers. Key words: controlled ice breakup, flood control, ice jams, ice management, river ice.

A conceptual model of river ice breakup

1984 ◽  
Vol 11 (3) ◽  
pp. 516-529 ◽  
Author(s):  
S. Beltaos
Keyword(s):  
Conceptual Model ◽  
Water Surface ◽  
Flow Characteristics ◽  
Ice Cover ◽  
River Ice ◽  
Meandering Channel ◽  
Transverse Cracking ◽  
Ice Breakup ◽  
Pertinent Data ◽  
Short Term Forecasting

A conceptual model of ice breakup is formulated and used to analyze and compare data from four river gauge sites. Emphasis is on the development of generalized short-term forecasting methods, which to date have been site specific. The features to be forecast are the onset and flooding potential of breakup. These are related to the water surface width available for passage of the large sheets of ice that form by transverse cracking of the ice cover. Thus it is possible to study the effects of parameters such as ice cover dimensions and channel geometry. Owing to a lack of pertinent data, other parameters such as ice mechanical properties and flow characteristics are only considered indirectly. The mechanism of transverse cracking is examined in the light of recent field observations. Bending on planes parallel to the water surface, caused by stream curvature, could account for the observed crack spacing but more data are needed for positive conclusions. The present model does not apply in cases of “overmature” breakup, proximity of stage controls, and river planforms different from the single meandering channel type. Key words: breakup, cracks, field data, forecasting, gauge records, ice, ice clearing, ice sheets, model, onset, river ice, rivers.

Comparison of field data with theories on ice cover progression in large rivers

1984 ◽  
Vol 11 (4) ◽  
pp. 798-814 ◽  
Author(s):  
Bernard Michel
Keyword(s):  
Quantitative Determination ◽  
Key Words ◽  
Field Data ◽  
Ice Cover ◽  
Large Rivers ◽  
Ice Dynamics ◽  
Physical Mechanisms ◽  
Flow Parameters ◽  
Existing Data ◽  
St Lawrence River

There are many theories pertaining to the progression of ice covers in rivers fed by frazil slush and floes but very few have been examined critically by comparing them with field data. In this paper the existing theories on dynamic ice cover progression are reviewed, an additional one is proposed, and they are classified according to the physical mechanisms that are involved. Finally, they are compared with some existing field data for large rivers. The data are extremely scarce and difficult to obtain because of the costs involved and the dangers in traveling over thin ice when the ice cover is being formed.It is usually easier to get only the critical values of parameters giving the limits of ice cover progression. In this paper, complete data were taken from the St. Lawrence River, the Beauharnois Canal, and the La Grande Rivière where the ice thicknesses along with the flow parameters have been measured.In these cases the existing data are adequate, so they could be grouped to explain the various mechanisms involved and to obtain numerical values for their quantitative determination. Key words: glaciology, river ice, ice dynamics, fluvial processes, ice hydraulics.

scholarly journals Description and Analysis of a 20-Year (1960-79) Digital Ice-Concentration Database for the Great Lakes of North America

1983 ◽  
Vol 4 ◽  
pp. 14-18 ◽  
Author(s):  
Raymond A. Assel
Keyword(s):  
North America ◽  
Great Lakes ◽  
Surface Area ◽  
Information Service ◽  
Grid Cell ◽  
Ice Cover ◽  
Unit Surface Area ◽  
Grid Cells ◽  
Data Set ◽  
Ice Concentration

A digital ice-concentration database spanning 20 years (1960 to 1979) was established for the Great Lakes of North America. Data on ice concentration, i.e. the percentage of a unit surface area of the lake that is ice-covered, were abstracted from over 2 800 historic ice charts produced by United States and Canadian government agencies. The database consists of ice concentrations ranging from zero to 100% in 10% increments for individual grid cells of size 5 × 5 km constituting the surface area of each Great Lake. The data set for each of the Great Lakes was divided into half-month periods for statistical analysis. Maxinium, minimum, median, mode, and average ice-concentrations statistics were calculated for each grid cell and half-month period. A lakewide average value was then calculated for each of the half-month ice-concentration statistics for all grid cells for a given lake. Ice-cover variability and the normal extent and progression of the ice cover is discussed within the context of the lakewide averaged value of the minimum and maximum ice concentrations and the lakewide averaged value of the median ice concentrations, respectively. Differences in ice-cover variability among the five Great Lakes are related to mean lake depth and accumulated freezing degree-days. A Great Lakes ice atlas presenting a series of ice charts which depict the maximum, minimum, and median icecover concentrations for each of the Great Lakes for nine half-monthly periods, starting the last half of December and continuing through the last half of April will be published in 1983 by the National Oceanic and Atmospheric Administration (NOAA). The database will be archived at the National Snow and Ice Data Center of the National Environmental Satellite Data and Information Service (NESDIS) in Boulder, Colorado, USA, also in 1983.

Experience in developing a method for long-term forecasting of the ice breakup time for the Vyatka River basin

2021 ◽  
Vol 4 ◽  
pp. 99-111
Author(s):  
Y.A Pavroz . ◽  
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
River Basin ◽  
Geopotential Height ◽  
Sea Surface ◽  
River Ice ◽  
Northwest Pacific ◽  
Ice Breakup ◽  
The Impact ◽  
Breakup Time

An attempt is made to develop a method for long-term forecasting of the ice breakup time for the Vyatka River basin, to identify the impact of the distribution of sea surface temperature and geopotential height in the informative regions at the levels H100 and H500 over the Northern Hemisphere on the river ice breakup. The location and boundaries of the informative regions in the fields of H100 and H500 were revealed by the discriminant analysis, the EOF expansion coefficients of the fields of anomalies of monthly mean values of H100 and H500 for January and February and the anomalies of monthly mean sea surface temperature in the North Atlantic and Northwest Pacific were used as potential predictors. The stepwise regression analysis allowed deriving good and satisfactory (S/σ = 0.45–0.73) complex prognostic equations for forecasting the ice breakup time for the Vyatka River basin. The essential influence of H100 and H500 geopotential height fields and the spatial distribution of sea surface temperature anomalies in the North Atlantic and Northwest Pacific in January and February on the river ice breakup time is revealed. It is proposed to improve the method by considering the impact of air temperature, maximum ice thickness per winter, and other indirect characteristics on the processes of river ice breakup in the Vyatka River basin. Keywords: ice regime, long-range forecast, river ice breakup, expansion coefficients, geopotential height fields, spring ice phenomena, energy-active zones of the oceans, complex prognostic equation

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