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Arising out of fieldwork in the Canadian Rockies, this paper analyzes the role of bears in the conservation culture of Canadian national parks. Why is the presence of this large predator tolerated and even celebrated by some? And why do others fear and even despise this animal, whom they see as a danger and a menace, and resent its continued preservation? Bears may act as a token charismatic species in conservation mythology; they may be anthropomorphized into a cuddly roadside attraction evoking childhood nostalgia; or they may play the part of wrathful Nature guarding against human incursion into the wilderness. Tourists in Banff National Park take great pains to see bears, while local hikers and campers expend almost equal energy avoiding an ursine encounter. This paper explores what human reactions to bears reveal about social attitudes toward the natural world, particularly in areas like the Canadian Rockies where human and bear territory overlap. [ABSTRACT FROM AUTHOR]

The early photographs of Canadian mountaineering are a unique genre of historical evidence that serve two functions: (1) they provide pictorial representations of the mountain scenery that supplement literary representations; (2) they are also an artifact of a kinetic event, the act of photographing. This paper considers journals, monographs and photographs from British and Canadian mountaineers. However, the specific focus is on the production and consumption of mountaineering photographs produced in the Canadian Rocky and Selkirk mountains between 1880 and 1920. While mountaineers made pioneering climbs in the Rocky and Selkirk ranges, their desire to reproduce the event brought additional meaning to the experience. Portable cameras and the event of photographing served this desire. As historical evidence, photographs are not merely reproductions of what they saw. They are extensions of what they desired to see as well as extensions of what they desired to feel. Photographs reveal a sensibility that is not evident in the written discourse. Through their cameras they cultivated a new and non-traditional way experiencing their surroundings and their bodies. Different ways of using the camera enabled this generation of mountaineer-sportsmen to constitute themselves as subjects of modernism. This paper demonstrates how ideas about modernist aesthetics provide an interesting and provocative analytical framework for the history of sport. [ABSTRACT FROM AUTHOR]

Case studies are presented in this paper to demonstrate the use of the pressure/rate deconvolution-approach in estimating drainage areas for wells completed in some of the naturally fractured tight gas reservoirs of the Canadian Rockies foothills. These case studies demonstrate the application of deconvolution to two key carbonate-stratigraphical horizons in the area: the Triassic Baldonnel and the Permo-Carboniferous Taylor Flat formations. In these structural plays with significant areal formation-rock heterogeneity, the matrix-rock properties controlling the gas storativity are low, with porosity between 3 and 6%, causing low matrix-rock permeability (from 0.01 and 0.1 md). However, all of these formations have been thrusted, overturned, and subjected to reverse faulting. These diagenetic factors have created swarms of natural fractures that control flow rates and may define rock volumes connected to individual wells. In each well, a preproduction flow test was performed with the intent of ensuring acceptable flow rates and scoping facility design. At this stage of early development, initial-gas-in-place (IGIP) estimates were derived mainly from geophysical mapping, with plans to calibrate the IGIP number through the application of gas material balance, rate-transient analysis, and/or simple latetime rate decline. The rate-history data available in the early stage of production were integrated with pressure-buildup (PBU) data collected later in the production life of the well during annual or routine shut-in periods that were relatively short. Application of deconvolution in this paper is aimed at detecting early signs of pseudosteady-state pool depletion and estimating connected drainage volume. The deconvolution procedures help calibrate and/or reconcile geosciences-defined volumetric resource sizes, map remaining reserves, and help identify possible infill-drilling opportunities. [ABSTRACT FROM AUTHOR]

This essay explores the complex struggles over the reinvention of mountaineering practices and ethics during the postwar period in the Rocky Mountains of Canada between competing interest groups of disparate climbers. Specifically, we focus on the increased challenges to the hegemony of the Alpine Club of Canada (ACC) by a wave of young, working-class emigrants, who contentiously broadened the limits and operative goals/meanings of the sport in the range. In doing so, this paper examines the controversy that erupted within the climbing community over first ascent of Brussels Peak in 1948, followed by a discussion of the arrival of renowned climber Hans Gmoser (1932-2006), whose early activities in the Rockies' eastern front irrevocably challenged local tradition and the hegemony of the ACC. [ABSTRACT FROM AUTHOR]

1. Elevational gradients create environmental variation that is hypothesized to promote variation in life-history strategies. We tested whether differences in life-history strategies were associated with elevation in a songbird, the dark-eyed junco ( Junco hyemalis; Aves; A.O.U. 1998 ). 2. We monitored birds in four replicated sites per elevation, at 2000 m a.s.l. (high elevation) and 1000 m a.s.l. (low elevation), in the Rocky Mountains of Canada. 3. Over 5 years, we measured the following traits and vital rates: egg-laying schedules, morphological indicators of reproductive stage, seasonal reproductive success, indicators of competitive class (age, size, arrival time), and survival rates. 4. We found two main patterns: with an increase in breeding elevation, dark-eyed juncos delayed the development of structures necessary for reproduction (e.g. cloacal protuberance in males) and reduced the duration of their reproductive period to less than half of the time used by low-elevation birds; and 5. Juncos at high-elevation sites had 55–61% lower annual reproductive success and 15 to 20% higher survival rates. While adult juncos at high elevations produced fewer offspring, those offspring were in better condition. Proportions of age and size classes in high- compared to low-elevation populations were similar, suggesting that a life-history trade-off is present, rather than competition forcing inferior competitors to breed in a peripheral habitat. The apparent trade-off between reproduction and survival corresponded to a shorter period of favourable weather and available food in high- compared to low-elevation habitats. 6. Thus, elevation had a strong influence on life-history characteristics of a single species over a short spatial distance, suggesting a shift in life history from a high reproductive strategy at lower elevations to a high survivor strategy at high elevations. 7. This is the first paper to show a shift in avian life-history strategies along an elevational gradient (in both genders, of multiple age classes) when region (latitude) and phylogenetic histories are controlled for. [ABSTRACT FROM AUTHOR]

Precipitation events that bring rain and snow to the Banff–Calgary area of Alberta are a critical aspect of the region's water cycle and can lead to major flooding events such as the June 2013 event that was the second most costly natural disaster in Canadian history. Because no special atmospheric-oriented observations of these events have been made, a field experiment was conducted in March and April 2015 in Kananaskis, Alberta, to begin to fill this gap. The goal was to characterize and better understand the formation of the precipitation at the surface during spring 2015 at a specific location in the Kananaskis Valley. Within the experiment, detailed measurements of precipitation and weather conditions were obtained, a vertically pointing Doppler radar was deployed and weather balloons were released. Although 17 precipitation events occurred, this period was associated with much less precipitation than normal (−35%) and above-normal temperatures (2.5°C). Of the 133h of observed precipitation, solid precipitation occurred 71% of the time, mixed precipitation occurred 9% and rain occurred 20%. An analysis of 17504 precipitation particles from 1181 images showed that a wide variety of crystals and aggregates occurred and approximately 63% showed signs of riming. This was largely independent of whether flows aloft were upslope (easterly) or downslope (westerly). In the often sub-saturated surface conditions, hydrometeors containing ice occurred at temperatures as high as 9°C. Radar structures aloft were highly variable with reflectivity sometimes  > 30dBZe and Doppler velocity up to −1ms−1, which indicates upward motion of particles within ascending air masses. Precipitation was formed in this region within cloud fields sometimes having variable structures and within which supercooled water at least sometimes existed to produce accreted particles massive enough to reach the surface through the relatively dry sub-cloud region. [ABSTRACT FROM AUTHOR]

A physically based model built upon extensive field observations of radiation dynamics and snow processes in cold regions forest environments was used to investigate the impacts of prescribed forest gap-thinning treatments on spring snowmelt in a small Saskatchewan River headwater basin of the Canadian Rocky Mountains. Both field observations and model simulations showed that snow accumulations in small clear-cut gaps was roughly double those under intact forest cover due to sublimation losses from the canopy. Consequently, mountain forests thinned with small clear-cut gaps resulted in a substantial increase in the magnitude of spring snowmelt. However, the impact of forest thinning on the timing of snowmelt was highly dependent on slope orientation; thinning accelerated snowmelt on south facing slopes primarily through enhanced shortwave radiation, but retarded snowmelt on north facing slopes primarily through reduced incoming longwave radiation. As a result, thinning treatments across opposing north facing and south facing mountain slopes acted to substantially expand the spring melt period in the basin, and illustrated the important hydrological control imparted by intact forest cover through its synchronization of snowmelt across complex terrain. A sensitivity analysis of snowmelt timing to varying spring meteorological conditions strongly suggests that shifts in spring snowmelt runoff from similar forest thinning treatments in mountain regions will depend on the slope and aspect at which they occur in combination with the seasonal timing of snowmelt resulting from latitude-controlled solar elevation effects. [ABSTRACT FROM AUTHOR]

The article presents the findings from a study that compares the alpine watershed characteristics in the Canadian Rocky Mountains based on data obtained from three digital elevation models (DEMs). The terrain topological information resources are the archived public access Terrain Resource Information Management (TRIM), stereo aerial photography DEM and airborne light detection and ranging (LiDAR). These three DEMs showed similar findings in terms of alpine basin attributes, however, significant differences were also found in the context of application uses and other finer scales.

Fresh snow samples were collected following seven snow accumulation events along an altitudinal transect of the Robertson Valley. This glacierized valley is on the eastern slopes of the Canadian Rockies at the Continental Divide and receives precipitation from both westerly (Pacific) air masses and from easterly (upslope) systems. Snow samples were collected over two winter seasons and were analyzed for δ18O, revealing altitudinal gradients that ranged from -0.3%/100 m to +1.8‰/100 m. Five of seven snow events had positive (inverse) isotopic gradients with altitude: 18O enrichment at higher altitudes. Surface and upper-air meteorological data were analyzed to classify the type of weather systems bringing precipitation to the area for each accumulation event. Three storm classifications were developed: westerly, upslope, and mixed/ northwesterly systems. Positive δ18O-elevation gradients were found under strong westerly and northwesterly flow, when the Robertson Valley acts as a leeward slope, while more conventional negative gradients correspond with upslope flow, when easterly winds make the Robertson Valley a windward snow deposition environment. We interpret the inverse isotopic gradients as evidence of ongoing Rayleigh distillation as westerly systems cross the Continental Divide. Position on the Rayleigh distillation curve had a strong influence on the magnitude of δ18O-elevation gradients. [ABSTRACT FROM AUTHOR]

The article explores whether atmospheric circulation indices derived from the NCEP-NCAR reanalysis dataset can be used in predicting regional climate anomalies and glacier mass balance in the Canadian Rockies. Jasper climate anomalies, regional climate anomalies and atmospheric flow indices were used to construct regression models for winter, summer and annual mass balance variability for Peyto Glacier in Alberta, Canada, known to offer the best available mass balance time-series in the Canadian Rockies. Multiple coefficient of determination and variables retained in the stepwise regression analysis were then used to examine model performance. Results suggest that flow indices are stronger predictor of glacier mass balance in the Canadian Rocky Mountains.

Examines the paleotemperature record from Picea engelmannii tree-line sites in Canadian Rockies, British Columbia. Differences in tree species modelling techniques, spatial coverage and seasonal temperatures; Development of temperature reconstruction for the Banff-Jasper region; Regional estimates of temperature.