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In cold region environments, any alteration in the hydro-climatic regime can have profound impacts on river ice processes. This paper studies the implications of hydro-climatic trends on river ice processes, particularly on the freeze-up and ice-cover breakup along the Athabasca River in Fort McMurray in western Canada, which is an area very prone to ice-jam flooding. Using a stochastic approach in a one-dimensional hydrodynamic river ice model, a relationship between overbank flow and breakup discharge is established. Furthermore, the likelihood of ice-jam flooding in the future (2041–2070 period) is assessed by forcing a hydrological model with meteorological inputs from the Canadian regional climate model driven by two atmospheric–ocean general circulation climate models. Our results show that the probability of ice-jam flooding for the town of Fort McMurray in the future will be lower, but extreme ice-jam flood events are still probable. [ABSTRACT FROM AUTHOR]

Abstract Reducing the cost of hydrokinetic turbines is an important step in the commer-cialization of the technology. One of the costs of the implementation of hydrokinetic turbines is the selection of potential hydrokinetic sites. In this paper, it is proposed that site selection for a hydrokinetic turbine can be improved in river environments in Canada by the use of winter imagery that is available at little or no cost. This is of particular value to remote communities who power their community using diesel fuel, as some pay over $1.00 per kWh. It is shown that river sections that do not freeze during the winter have higher velocity magnitudes than sections that are covered with ice. The average velocity magnitude for open ice locations is found to be 1.09 m/s, with a standard deviation of 0.48 m/s. Ice covered locations were found to have an average velocity magnitude of 0.301 m/s. The relationship between river depth and velocity magnitude is shown to have a low correlation, with an R2 value of 0.185. [ABSTRACT FROM AUTHOR]

Greater opportunity now exists compared to 35 years ago for civil engineers to apply river ice knowledge to practical problems of planning, designing, and operating hydro-power facilities, water intakes, bridges, and other infrastructure along ice-covered rivers. This is due to major advancements made during this period in understanding the physical processes of river ice formation, growth and breakup, in developing instrumentation for acquisition of information on winter environments, and in developing numerical modelling tools. An increasing number of journal articles, as well as papers presented at the river ice workshops of the CGU Committee on River Ice Processes and the Environment (CRIPE) and the ice symposia of the International Association for Hydro-Environment Engineering and Research (IAHR) attest to the advancement in river ice science and engineering knowledge that has occurred during the past 35 years. This paper reviews the developments in river ice science and engineering from a Canadian perspective and briefly discusses future directions. [ABSTRACT FROM AUTHOR]

Ground-based, interferometric, synthetic aperture radar (GB-InSAR) has been successfully implemented for the monitoring and assessment of both natural and man-made slopes. Its advantages include high-frequency data acquisition and high spatial density, providing maps of displacement. The implementation of this tool for civil projects in remote areas and under severe weather conditions present several challenges. This paper presents the implementation of GB-InSAR, particularly using discrete monitoring campaigns and temporal aggregation of data, for resolving logistical issues associated with power availability. This was implemented to monitor a very slow-moving (average displacement rate of ~10 mm/y) 2 to 3 million m3 bedrock landslide known as The Checkerboard Creek Rock Slope located within the Revelstoke dam reservoir, BC, Canada. GB-InSAR deployment has been successful as it confirmed the toppling-like deformation mode, improved definition of the most active area within the exposed slope cut, improved understanding of the seasonality observed in some instruments at the site, and identification of a potential unstable block north of the known active area. Further, the findings in this paper verify the feasibility of implementing GB-InSAR technology to monitor similar slopes associated with the safety of civil infrastructure and in challenging conditions characteristic of the Canadian environment. • Discontinuous ground radar slope monitoring in remote, challenging environments. • Successful implementation and update of rock landslide deformation patterns. • Valuable insight into slow rock landslides without base sliding surface. • Precedent and guide for ground radar deployment in remote, challenging weather. • Updated information on known Canadian landslide Checkerboard Creek Rock Slope. [ABSTRACT FROM AUTHOR]

Sugar maple decline in eastern North America is caused by a complex combination of factors, with soil nutrition being one of several important determinants. Given the complexity of sugar maple population dynamics and the geographic extent of the species, we support Bailey et al.'s (2019, Can. J. For. Res. 49(7), doi:10.1139/cjfr-2018-0207) argument to interpret results from Cleavitt et al. (2018, Can. J. For. Res. 48(1): 23–31, doi:10.1139/cjfr-2017-0233) with due caution. The experiment at Hubbard Brook Experimental Forest represents an atypical application of contemporary forest practice in the White Mountain National Forest; however, some comments in Bailey et al. (2019) missed the point; others inaccurately characterized our paper. Cleavitt et al.'s (2018) 30-year record of vegetation recovery following whole-tree harvest documented a worrisome inability of a sugar maple population that successfully established after harvest to maintain its position in the understory. This lack of persistence on base-poor soils such as those in the mid and upper elevations of Hubbard Brook Experimental Forest suggests that the successful recruitment of sugar maple is not guaranteed. [ABSTRACT FROM AUTHOR]