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The Canadian Cordillera in the province of British Columbia witnesses numerous rock falls every year. Studies on the recorded rock fall data in this area show that rock fall hazard follows weather conditions, especially precipitation and freeze-thaw cycles. This relationship indicates that a weather-based approach can be implemented to estimate possible changes in the rock fall hazard due to climate change. In this paper, we used a statistical approach to quantify the relationship between monthly weather averages and rock fall frequencies for a section of a transportation corridor along the Fraser River in British Columbia, Canada. In this regard, von Mises distributions are used to find the best-fitted models to the monthly precipitation and freeze-thaw cycles, and proper relative weights are applied to the models in order to calibrate them to the rock fall monthly frequency. The calibrated model is used with input data from climatic predictions for 2041–2070 and 2071–2100 to see how rock fall distribution will be affected due to climate change in the future decades. Results show that between 9 and 19%, more rock fall is anticipated in future winters. Rock falls are expected to decrease in other months, especially in October, November, March, and April. This paper presents a method to predict changes in rock fall hazard seasonality due to climate change and illustrates the method with a case study along a section of the Canadian Cordillera. [ABSTRACT FROM AUTHOR]

Groundwater sustainability is challenged by the difference between legal and scientific understanding of groundwater, as well as the lack of focused attention to regulatory design in the literature on groundwater institutions, governance and management. The purpose of this paper is to use the scientific characteristics of groundwater to direct the necessary elements of regulatory design for this unique element. Developing interdisciplinary language that could be applied in any jurisdiction or region, the article describes seven groundwater characteristics as processes, functions, qualities, physical sustainability, scale, information and data, and physical state. Using these characteristics of groundwater embeds the scientific understanding of groundwater into regulatory design and enables the expression of new values such as Indigenous rights to water. Applying these scientific characteristics to a case study of new groundwater regulation in a subnational jurisdiction in the Global North—British Columbia (BC), Canada—highlights the failure of regulatory design even in a well-resourced jurisdiction where environmental regulation is the norm. Groundwater in BC is extremely heterogeneous in process and function, with low observation density and undefined sustainability goals where regulations are applied uniformly. Looking forward, three recommendations can be drawn using the scientific characteristics of groundwater to improve regulatory design in BC: defining sustainability goals and ecological thresholds; regionalizing and prioritizing; and long-term planning. This science-forward and interdisciplinary approach has implications for states with customary water entitlements and multiple legal orders. It also provides practitioners with an interdisciplinary language that can be useful for assessing current and future regulatory design. [ABSTRACT FROM AUTHOR]

This paper demonstrates knowledge-guided fuzzy logic modeling of regional-scale surficial uranium (U) prospectivity in British Columbia (Canada). The deposits/occurrences of surficial U in this region vary from those in Western Australia and Namibia; thus, requiring innovative and carefully-thought techniques of spatial evidence generation and integration. As novelty, this papers introduces a new weighted fuzzy algebraic sum operator to combine certain spatial evidence layers. The analysis trialed several layers of spatial evidence based on conceptual mineral system model of surficial U in British Columbia (Canada) as well as tested various models of evidence integration. Non-linear weighted functions of (a) spatial closeness to U-enriched felsic igneous rocks was employed as U-source spatial evidence, (b) spatial closeness to paleochannels as fluid pathways spatial evidence, and (c) surface water U content as chemical trap spatial evidence. The best models of prospectivity created by integrating the layers of spatial evidence for U-source, pathways and traps predicted at least 85% of the known surficial U deposits/occurrences in >10% of the study region with the highest prospectivity fuzzy scores. The results of analyses demonstrate that, employing the known deposits/occurrences of surficial U for scrutinizing the spatial evidence layers and the final models of prospectivity can pinpoint the most suitable critical processes and models of data integration to reduce bias in the analysis of mineral prospectivity. [ABSTRACT FROM AUTHOR]

Terrestrial lidar scanning (TLS) has become a widely accepted expert tool for monitoring geohazards on bare or sparsely vegetated slopes through change detection. While trees can be an important indicator of landslide activity at a slope, vegetation is often removed or ignored when monitoring landslides with TLS. This paper explores the use of multi-temporal terrestrial lidar scanning at a slope in the Peace River valley of British Columbia to test the author's hypothesis that tree stems in TLS data can be used to track landslide displacement and provide insight into the landslide mechanism. Six TLS datasets, each collected approximately 6 months apart, are used, and roto-translation methods are employed to determine the azimuth, plunge, and toppling angle of trees between each TLS scan. The tree displacement patterns are compared to TLS change detection results on bare-ground, and to single-point tracking techniques for extracting displacement vectors. Considerations for future applications are discussed. [ABSTRACT FROM AUTHOR]

The displacement of a large slow-moving landslide is accompanied by slope damage, such as fractures, tension cracks, and slope bulging. Studies of these features provide insight into the mechanisms responsible for the deformation. In this paper, we investigate slope damage at the Downie Slide, a very large landslide in British Columbia, Canada, that is slowly moving along two shear zones subparallel to the ground surface. Structural geology, and particularly the morphology of the lower shear zone, strongly controls the deformation and, in turn, the observed internal and surficial slope damage features. We use aerial and underground adit laser scanning and photogrammetry to characterize the geometry of the landslide. We subdivide the slide area into slope damage domains based on the distribution, size, and orientation of the slope damage features. We reconstruct the shape of the two failure surfaces by interpolating borehole inclinometer monitoring data and processing the 3D surfaces in a GIS environment to create aspect and slope maps. We observe a strong correlation between surficial slope damage features and changes in the dip and dip direction of the lower sliding surface. We further infer the presence of a multi-planar failure surface geometry and previously unrecognized structurally controlled damage zones. [ABSTRACT FROM AUTHOR]

In this paper, we examine the influence of the 27 October 2012, Mw 7.8 earthquake on landslide occurrence in the southern half of Haida Gwaii (formerly Queen Charlotte Islands), British Columbia, Canada. Our 1350 km2 study area is undisturbed, primarily forested terrain that has not experienced road building or timber harvesting. Our inventory of landslide polygons is based on optical airborne and spaceborne images acquired between 2007 and 2018, from which we extracted and mapped 446 individual landslides (an average of 33 landslides per 100 km2). The landslide rate in years without major earthquakes averages 19.4 per year, or 1.4/100 km2/year, and the annual average area covered by non-seismically triggered landslides is 35 ha/year. The number of landslides identified in imagery closely following the 2012 earthquake, and probably triggered by it, is 244 or an average of about 18 landslides per 100 km2. These landslides cover a total area of 461 ha. In the following years—2013–2016 and 2016–2018—the number of landslides fell, respectively, to 26 and 13.5 landslides per year. In non-earthquake years, most landslides happen on south-facing slopes, facing the prevailing winds. In contrast, during or immediately after the earthquake, up to 32% of the landslides occurred on north and northwest-facing slopes. Although we could not find imagery from the day after the earthquake, overview reconnaissance flights 10 and 16 days later showed that most of the landslides were recent, suggesting they were co-seismic. [ABSTRACT FROM AUTHOR]

The five great trans-Pacific tsunamis of the 20th century that occurred in 1946, 1952, 1957, 1960 and 1964 were accurately recorded by analogue tide gauges on the coast of British Columbia. All available pen-and-paper records of these events were collected, digitised, de-tided and analysed. The 1946 Aleutian Islands event was recorded at two stations, Tofino and Victoria, where maximum trough-to-crest tsunami wave heights were 55 and 27 cm, respectively. These two gauged stations, as well as Prince Rupert, Alert Bay and Kitimat, also recorded the 1952 Kamchatka tsunami, which generated a maximum wave height of 77 cm at Tofino. The 1957 Andreanof Islands tsunami was recorded at six primary stations and the 1960 Chile tsunami by 17 primary and temporary tide gauges. For both of these events, the maximum tsunami wave heights also occurred at Tofino: 48 cm (1957) and 132 cm (1960). The 1964 Alaska tsunami remains the strongest tsunami yet instrumentally recorded on the coast of British Columbia. Our examination of 16 records from this event shows that maximum wave heights at eight stations were higher than 1 m, including Port Alberni (770 cm), Ocean Falls (376 cm), Tofino (237 cm) and Alert Bay (222 cm). We also find that the maximum wave at all stations for this event was among the first three waves. Subsequent wave heights rapidly attenuated following this group of waves. Frequency-time (f–t) analyses of the tsunami waveforms reveal that, for each station, the dominant frequencies of the waves and their evolution with time were very similar for different tsunamis, but differed considerably among sites for a particular tsunami, indicating the strong influence of local/regional topography on the incoming waves. From the latter point of view, the 1964 tsunami was exceptional. The epicentre of the 1964 Alaska earthquake was located much closer to the BC coast than for the other events and, therefore, the influence of the source was much stronger. The "ringing" of this tsunami was substantially shorter (< 1.5 days), the energy decay much faster, and the f–t diagrams at all sites more similar than for the other major events. During the 1964 event, energy associated with the dominant period of 2 h rapidly decayed. All of the tsunamis examined penetrated deep inside the narrow channels, fjords and inlets, typical of the BC coast. Waves also propagated far into some of the rivers. The 1952 Kamchatka tsunami was recorded at Kitimat, located at the head of Kitimat Arm about 80 km from Hecate Strait, while the 1957 Andreanof Islands tsunami was measured at Bella Coola, located at the remotest part of Burke Channel, a distance of ~110 km from the open ocean (Queen Charlotte Sound). The 1960 Chile tsunami was recorded at five stations located in the complex network of inlets and channels that make up the Seymour–Belize Inlet system on the central mainland coast of British Columbia, while the 1964 Alaska tsunami was observed at many stations in the Fraser River, including Pitt Lake that is connected to the Strait of Georgia through a 64-km route upstream in the Fraser and Pitt rivers. Our results further show that occasionally the fjords and inlets of the BC coast not only do not hinder the incoming waves but can strongly enhance them through resonant amplification. This was the case for the 1964 tsunami waves in Alberni Inlet, where the resonant response to the incoming waves resulted in severe damage to Port Alberni at the head of the inlet. The results of our analyses make it possible to isolate the tsunami signal and evaluate the principal parameters of tsunami waves. This, in turn, is of considerable value for three major problems: (1) Cataloguing of tsunami events; (2) estimation of the potential tsunami risk to the BC coast; and (3) verification and calibration of numerical tsunami models. [ABSTRACT FROM AUTHOR]

Analysing sexual harassment law in British Columbia, this paper argues that in highly sexualised work environments, in which practices including sexual 'jokes' or innuendo may be common, law embodies and (re)creates the gendered subtext of the workplace. When a complaint of sexual harassment from a sexualised workplace is raised in a legal forum, a complainant has an obligation to clearly object to the sexual remarks, 'jokes,' banter, etc.-which may be the 'norm'-to show the conduct in question was unwelcome. At the same time, however, a workplace may be structured, in part by law, in a way that restricts employee resistance to uncomfortable sexual experiences. This is the case, I argue, for women working in full-service restaurants when it comes to sexual interactions with customers. This paper explores how restaurant work, in the Canadian context with a focus on the province of British Columbia, is organised in a manner that makes women vulnerable to enduring sexually harassing practices as a routine part of their jobs. [ABSTRACT FROM AUTHOR]

The Thompson River valley, south of Ashcroft in British Columbia, Canada, has experienced several landslides since the mid-1800s. The national railways that run along the valley cross a number of these landslides. All the landslides occur in glacial deposits, typically sliding on weak clay layers. Some have failed rapidly to very rapidly and are currently inactive or showing deformation rates from a few millimeters to centimeters per year. An evaluation of satellite InSAR (Interferometric Synthetic Aperture Radar) using RADARSAT-2 images between September 2013 and November 2015 provides new insight into landslide displacements in the Thompson River valley. This information enhances the ongoing hazard management of unstable terrain. This paper presents the comparison of the InSAR measurements with other instrumentation (GPS and ShapeAccelArrays™ -SAA) installed at one moving landslide and then addresses the extent and magnitude of the slope movements observed. InSAR was found to provide similar displacement values to those measured otherwise. The stable location showed displacements of +/−1 mm with an average near zero during the whole monitoring period. Six areas of slope movement were identified within the study area, all within or adjacent to the footprints of past landslides. The average line of sight (LOS) displacement rates range between 11 and 39 mm/year. Most of the landslides exhibited seasonal variations in velocity that corresponds to changes in river elevation in the valley. [ABSTRACT FROM AUTHOR]

Background: British Columbia's (BC) extensive forest resources provide climate change mitigation opportunities that are available to few other jurisdictions. However, as a consequence of the Mountain Pine Beetle outbreak and large-scale wildfires, BC is anticipating reduced roundwood harvest for the next decades. Progress towards more climatically efficient utilization of forest resources is needed. This research quantitatively compared the greenhouse gas emission consequences of nine harvested wood products trade and consumption strategies. Inward-focused strategies use wood products within Canada to achieve emission reduction objectives, while outward-focused strategies encourage exports of wood products. Results: In the business-as-usual baseline scenario, average emissions arising from BC-originated harvested wood products between 2016 and 2050 were 40 MtCO2e yr−1. The estimated theoretical boundaries were 11 MtCO2e yr−1 and 54 MtCO2e yr−1, under the scenarios of using all harvests for either construction purposes or biofuel production, respectively. Due to the constrained domestic market size, inward-focused scenarios that were based on population and market capacity achieved 0.3–10% emission reductions compared to the baseline. The international markets were larger, however the emissions varied substantially between 68% reduction and 25% increase depending on wood products' end uses. Conclusions: Future bioeconomy strategies can have a substantial impact on emissions. This analysis revealed that from a carbon storage and emission perspective, it was better to consume BC's harvests within Canada and only export those products that would be used for long-lived construction applications, provided that construction market access beyond the US was available. However, restricting export of wood products destined for short-lived uses such as pulp and wood pellets would have significant economic and social impacts. On the other hand, inward-focused strategies had a small but politically and environmentally meaningful contribution to BC's climate action plan. This study also revealed the conflicts between a demand-driven bioeconomy and targeted environmental outcomes. A hierarchical incentive system that could co-exist with other market drivers may help achieve emission reduction goals, but this would require a better quantitative understanding of wood products' substitution effects. While the analyses were conducted for BC, other regions that are net exporters of wood products may face similar issues. [ABSTRACT FROM AUTHOR]

Background: Cholecystitis and gallstones affect a large segment of the population in developed nations, and a small proportion of affected individuals subsequently develop cancer of the gallbladder. However, little is known about the possible beneficial effects of physical activity. Objective: Accordingly, a systematic review examined the influence of both acute and chronic exercise on gallbladder motility, and relationships were examined between habitual physical activity, gallbladder disease, and gallbladder cancer. Methods: A search of Ovid/MEDLINE from 1996 to November 2014 yielded 67 articles relating to physical activity and gallbladder function or disease; 18 of these relevant to the objectives of the review were supplemented by 22 papers from personal files and other sources. Because of the limited volume of material, all were considered, although note was taken of the quality of activity measurement, care in excluding covariates, and experimental design (cross-sectional, case-control or randomized controlled trial). Results: The impact of physical activity upon gallbladder function remains unclear; acute activity could augment emptying by stimulating cholecystokinin release, and one of two training experiments found a small increase in gallbladder motility. The largest and most recent cross-sectional and case-control trials show a reduced risk of gallbladder disease in active individuals. A small number of randomized controlled trials in humans and one animal study generally support these trends, although the number of cases of gallstones are too few for statistical significance. Three studies of gallbladder cancer also show a non-significant trend to benefit from physical activity. Conclusions: Although there remains a need for further research, regular physical activity seems likely to reduce the risk of both gallstones and gallbladder cancer. A substantial number of individuals must be persuaded to exercise in order to avoid one case of gallbladder disease, but the attempt appears warranted because of the other health benefits of regular physical activity. [ABSTRACT FROM AUTHOR]

The main purpose of this prospective study is to validate the construct of psychosocial well-being (PSWB) for people with severe mental disorders enrolled in Supported Employment (SE) programs. This paper also aims to assess the impact of job acquisition on PSWB after obtaining competitive employment. A two-phase study approach was used and 231 individuals with severe mental disorders enrolled in SE programs who took part in both phases. The shortened versions of the Psychological Well-Being Scale (Keyes et al. in J Personal Soc Psychol, 82(6):1007-1022, ; Ryff and Keyes in J Personal Soc Psychol 69(4):719-727, ) and the Social Well-Being Scale (Keyes in Soc Psychol Q 61(2):121-140, ) were used. The PSWB's multidimensionality construct was confirmed. The results of repeated measure ANOVA analyses revealed that job acquisition, as well as, being involved in a work-seeking process increase the PSWB of people with severe mental disorders. Employment specialists might find clinical utility in using this validated tool for assessing PSWB in their clients with severe mental disorders. In a recovery oriented approach to psychiatric services and SE programs, clinicians and employment specialists should continue to encourage their clients in their work integration process even though they may not all obtain competitive employment quickly. [ABSTRACT FROM AUTHOR]