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In this paper, we put forward a proposal for a critical geography of physical activity that attunes to experience while centring on the socio‐spatial processes and power structures enabling and constraining physical activity participation. Drawing on our research that explored women's and men's emotional geographies of an everyday exercise environment – the gym – in a Canadian city, we show how this approach can identify otherwise invisible environmental influences on physical activity participation. Our thematic analysis reveals that the gym environment is generative of three place‐based emotive processes of dislocation, evaluation, and sexualisation that collectively configure an unevenly gendered emotional architecture of place. Through this interstitial structure, the boundaries of localised hierarchies of masculinities and femininities become felt in ways that create tensions and anxieties, which in turn reinforce gendered boundaries on physical activity participation. Two additional themes reveal how gendered motivation and individual factors mediate negative emotional experiences. Our findings indicate that emotional geographies are one way in which gender disparities in physical activity are naturalised at the scale of the everyday exercise environment. Interventions for gender equity in physical activity would benefit from being empathetically attuned to the subtleties of place‐based experiences. More widely, bringing emotions into geographies of physical activity sheds light on the larger question of the role of place in (re)producing gendered health inequities, with implications for geographical research on health and social justice. Future critical geographical inquiry is necessary to ensure that public health interventions are grounded in the experiential realities of practising physical activity in particular places. [ABSTRACT FROM AUTHOR]

Salt marshes are highly effective carbon (C) sinks and have higher rates of soil C burial (per square meter) than terrestrial ecosystems. Marsh reclamation and anthropogenic impacts, however, have resulted in extensive losses of salt marshes. Restoration of marshes drained and “reclaimed” for agriculture (referred to in Canada as dykelands) and degraded marshes can generate C credits, but only if C burial is reliably quantified. To date, studies reporting on C burial rates have been limited primarily to restored marshes which are more than 10 years old. Here we report on a study which assessed C burial six years after the return of tidal flooding to a section of dykeland in Aulac, New Brunswick on Canada’s Bay of Fundy. The C burial rate in the restored marsh averaged 1 329 g C m-2 yr-1, more than five times the rate reported for a nearby mature marsh. Carbon density in the recovering marsh was relatively consistent with depth and although salt marsh cordgrass (Spartina alterniflora) became established in 2012, the bulk of the C in the new marsh deposit is assumed to be allochthonous. Financial constraints are a barrier to marsh restoration projects and C markets could provide a considerable source of funding for restoration work in the future. For marsh restoration projects to be recognized in C crediting systems, however, it must also be demonstrated that the allochthonous C would not otherwise have been sequestered; the potential for this is discussed. [ABSTRACT FROM AUTHOR]

As suggested by Ashmore and Dodson (), emphasis on urban physical geography would contribute to deeper understandings about the Anthropocene, while supporting the management of more livable cities and suburbs. Urban physical geography can look to urban ecology for conceptual models that will support exploration of urban areas as unique socio-ecological systems. There are, however, institutional barriers to achieving a more robust urban physical geography in Canada. These include the siloed structure of the main funding bodies and traditional separation of human and physical geography in undergraduate programs. While overcoming these barriers is not easy, urban physical geography has the potential to provide critical insights into the places where most Canadians live and work. [ABSTRACT FROM AUTHOR]

The Critical Zone is an interdisciplinary theme for environmental research that considers the near surface environment of the Earth and interactions amongst rock, soil, water, air, and living organisms. Critical Zone research initiatives in the United States (US) have met with great success, with multiple Critical Zone Observatories located in a variety of regional field settings at their core. These initiatives have allowed for enormous advances in addressing interdisciplinary environmental science questions based on team collaborations involving experts from various disciplines. The Critical Zone initiative in the US is now being extended to several other countries, but Canada has not been a participant in initial meetings involving various national funding agencies and researchers from different countries. Because physical geographers study a wide range of topics falling under the banner of Critical Zone science (including soils, hydrology, geomorphology, climatology, glaciology, biogeography), they are well poised to be active participants in national strategies for Critical Zone science. Suggestions are provided for moving towards a national strategy for Critical Zone science initiatives in Canada that connect to recent international developments. Vers une stratégie pour la science de la zone critique au Canada La zone critique est un thème interdisciplinaire de la recherche environnementale qui examine le milieu de la proche surface de la Terre et les interactions entre la roche, le sol, l'eau, l'air et les organismes vivants. Les initiatives de recherche en zone critique aux États-Unis ont connu beaucoup de succès grâce à de nombreux observatoires de la zone critique situés au centre de divers dispositifs d'études régionales. Ces initiatives ont permis d'accomplir d'énormes progrès en abordant des questions de science environnementale interdisciplinaire fondées sur la collaboration d'équipes impliquant des spécialistes de diverses disciplines. Les initiatives américaines en zone critique sont maintenant étendues à de nombreux autres pays, mais le Canada n'a pas participé aux premières réunions impliquant divers organismes nationaux de financement ainsi que des chercheurs de différents pays. Comme les géographes spécialisés en géographie physique étudient un large éventail de thèmes placés sous la bannière de la science de la zone critique (y compris les sols, l'hydrologie, la géomorphologie, la climatologie, la glaciologie, la biogéographie), ils sont bien placés pour participer activement aux stratégies nationales pour la science de la zone critique. Des suggestions sont faites dans le but d'adopter une stratégie nationale pour les initiatives concernant la science de la zone critique au Canada qui se rattachent aux récents progrès internationaux. [ABSTRACT FROM AUTHOR]

Observations of the interactions of large amplitude internal seiches with the sloping boundary of Lake Simcoe, Canada show a pronounced asymmetry between up- and downwelling. Data were obtained during a 42-day period in late summer with an ADCP and an array of four thermistor chains located in a 5 km line at the depths where the thermocline intersects the shallow slope of the lakebed. The thermocline is located at depths of 12–14 m during the strongly stratified period of late summer. During periods of strong westerly winds the thermocline is deflected as much as 8 m vertically and interacts directly with the lakebed at depth between 14–18 m. When the thermocline was rising at the boundary, the stratification resembles a turbulent bore that propagates up the sloping lakebed with a speed of 0.05–0.15 m s−1 and a Froude number close to unity. There were strong temperature overturns associated with the abrupt changes in temperature across the bore. Based on the size of overturns in the near bed stratification, we show that the inferred turbulent diffusivity varies by up to two orders of magnitude between up- and downwellings. When the thermocline was rising, estimates of turbulent diffusivity were high with KZ ∼10−4 m2s−1, whereas during downwelling events the near-bed stratification was greatly increased and the turbulence was reduced. This asymmetry is consistent with previous field observations and underlines the importance of shear-induced convection in benthic bottom boundary layers of stratified lakes. [ABSTRACT FROM AUTHOR]

Geomorphology in Canada, as elsewhere, has evolved into an essentially bipartite discipline focusing either on ‘process’ or broader ‘historical’ (Quaternary) landscape interpretation. A growing emphasis on process-oriented research that relies increasingly on instrumentation and computational technologies has occurred. Critics of such research note limited applicability for landscape evolution, fashionability of methods and limited societal relevance. Indeed, some say we are not seeing the landscape for the processes. This article discusses the changing nature of geomorphology since the Quantitative Revolution of the 1950s including new advances, recent trends and challenges. Publication trends and recent advances suggest that the discipline is very healthy (following a slump in the early 1990s) and continues to evolve, which may reflect increasing research infrastructure and/or funding opportunities and new publications spotlighting Canadian research. Unfortunately, fundamental (less applied) research is threatened by funding program shifts, changing institutional pressures and a decline in research capacity from retirement attrition, and student recruitment challenges. Three research priorities are recommended: (1) continued fundamental research, (2) more integrated modelling to link micro scale processes to macro scale landform behaviour and (3) improvements in profiling our discipline amongst students and related professionals. [ABSTRACT FROM AUTHOR]

Small impact events recorded on the surface of Earth are significantly underrepresented based on expected magnitude-frequency relations. We report the discovery of a 36-m-diameter late Holocene impact crater located in a forested area near the town of Whitecourt, Alberta, Canada. Although undetectable using visible imagery, the presence of the crater is revealed using a bare-Earth digital elevation model obtained through airborne light detection and ranging (LiDAR). The target material comprises deglacial Quaternary sediments, with impact ejecta burying a late Holocene soil dated to ca. 1100 14C yr B.P. Most of the 74 iron meteorites (0.1-1196 g) recovered have an angular exterior morphology. These meteorites were buried at depths <25 cm and are interpreted to result from fragmentation of the original projectile mass, either at low altitude or during the impact event. Impact of the main mass formed the simple bowl-shaped impact structure associated with an ejecta blanket and crater fill. The increasing availability of LiDAR data for many terrestrial surfaces will serve as a useful tool in the discovery of additional small impact features. [ABSTRACT FROM AUTHOR]

Regional-scale spatial variation in the change in equilibrium-line altitude (ELA) trend surface in the Queen Elizabeth Islands (QEI), Arctic Canada between the 'Little Ice Age' (LIA) and 1960 corresponds to Empirical Orthogonal Functions (EOFs) representing specific patterns of summer climate variability found in the modern record. Extreme warm (1953-1962) and cold (1965-1974) decades in the modern record were used as modern analogues of climatic conditions during the early twentieth century and the LIA, respectively. Because of the minimal influence of precipitation during both extreme decades, temperature is the variable upon which the fluctuation of the ELA is dependent. Hence, the ELA ?h pattern describes the spatial pattern of change in SAT across the QEI between the LIA and 1960. This pattern is consistent with the primary mode of variability of mean summer surface air temperature (SAT) in the modern record (ie, EOF-1, 1949-2002), the positive (negative) phase of which is strongly in place during the extreme warm (cold) decade. SAT anomalies in the QEI during the warm (cold) decade are positively correlated with a weak (strong) QEI-distal (QEIproximal) polar vortex, higher (lower) than normal SSTs in the North Atlantic, and one of the lowest (highest) periods of sea-ice extent during the twentieth century. The climatic conditions during the cold decade are believed to describe conditions, which if sustained, would lead to a LIA-type cold episode capable of long-term snowline lowering and perennial snow/ice expansion. The climatic conditions during the warm decade represent possible modern analogues for those that might have occurred during the early twentieth century in the Canadian High Arctic, which led to a substantial reduction in perennial snow/ice. [ABSTRACT FROM AUTHOR]

Changes in late Neoglaical climate resulted in extensive modification of Arctic terrestrial ice cover. A substantial reduction in terrestrial ice cover in the Queen Elizabeth Islands (QEI) following the 'Little Ice Age' (LIA) (~AD 1250-1900), is indicated by widespread, light-toned patches of poorly vegetated terrain, extending back to the modern ice mass. These patches display abrupt outer margins (trimlines), which record the former position and maximum extent of perennial snow/ice and, in many cases, mark the former equilibrium-line altitude (ELA). Trimlines surrounding terrain formerly covered by LIA perennial snow/ice were mapped using multispectral classification approaches applied to high-resolution satellite imagery. ELAs were reconstructed from trimlines associated with former perennial snow/ice produced by long-term snowline lowering. Between the end of the LIA and 1960, the area of terrestrial ice in the QEI decreased by 37% (62 387 km2). Most of this reduction (94%) occurred in the eastern QEI where the majority of the ice exists today; however, a 100% reduction in ice cover occurred on many of the western islands by 1960, an effect largely controlled by the subtle topography of these islands. The reconstructed LIA ELA trend surface was used with the 1960 mapped ELAs to calculate spatial variations in the change in height (Δh) of the ELA trend surface throughout the QEI during the first half of the twentieth century. ELA Δh between the LIA and 1960 reveal a high degree of local variability in the mountainous regions, ranging from 0 to >600 m; however a strong regional-scale pattern of change is shown over the QEI as a whole. [ABSTRACT FROM AUTHOR]

Abstract: Patterns of coastal erosion in the Arctic differ dramatically from those coasts in more temperate environments. Thick sea ice and shore-fast ice limit wave-based erosional processes to a brief open water season, however despite this, permafrost coasts containing massive ice, ice wedges and ice-bonded sediments tend to experience high rates of erosion. These high rates of erosion reflect the combined thermal–mechanical processes of thawing permafrost, melting ground ice, and wave action. Climate change in the Arctic is expected to result in increased rates of coastal erosion due to warming permafrost, increasing active layer depths and thermokarst, rising sea levels, reduction in sea ice extent and duration, and increasing storm impacts. With the most ice-rich permafrost in the Canadian Arctic, the southern Beaufort Sea coast between the Tuktoyaktuk Peninsula and the Alaskan border is subject to high rates of erosion and retrogressive thaw slump activity. Under many climate change scenarios this area is also predicted to experience the greatest warming in the Canadian Arctic. This paper presents results of a remote sensing study on the long-term patterns of coastal erosion and retrogressive thaw slump activity for Herschel Island in the northern Yukon Territory. Using orthorectified airphotos from 1952 and 1970 and an Ikonos image from 2000 corrected with control points collected by kinematic differential global positioning system and processed using softcopy photogrammetric tools, mean coastal retreat rates of 0.61 m/yr and 0.45 m/yr were calculated for the periods 1952–1970 and 1970–2000, respectively. The highest coastal retreat rates are on north–west facing shorelines which correspond to the main direction of storm-related wave attack. During the period 1970–2000 coastal retreat rates for south to south–east facing shorelines displayed a distinct increase even though these are the most sheltered orientations. However, south to south–east facing shorelines correspond to the orientations where the highest densities of retrogressive thaw slumps are observed. Differences in rates of headwall retreat of retrogressive thaw slumps and coastal erosion results in the formation of larger thermokarst scars and the development of polycyclic thaw slumps on south to south–east exposures. The number and the total area of retrogressive thaw slumps increased by 125% and 160%, respectively, between 1952 and 2000. As well, the proportion of active retrogressive thaw slumps increased dramatically. Polycyclic retrogressive thaw slumps appear to develop in a periodic fashion, related to retrogressive thaw slump stage and maximum inland extent. [Copyright &y& Elsevier]

The Kaskapau Formation spans Late Cenomanian to Middle Turonian time and was deposited on a low-gradient, shallow, storm-dominated muddy ramp. Dense well log control, coupled with exposure on both proximal and distal margins of the basin allows mapping of sedimentary facies over about 35 000 km2. The studied portion of the Kaskapau Formation is a mudstone-dominated wedge that thins from 700 m in the proximal foredeep to 50 m near the forebulge about 300 km distant. Regional flooding surfaces permit mapping of 28 allomembers, each of which represent an average of ca 125 kyr. More than 200 km from shore, calcareous silty claystone predominates, whereas 100 to 200 km offshore, mudstone and siltstone predominate. From about 30 to 100 km offshore, centimetre-bedded very fine sandstone and mudstone record along-shelf (SSE)-directed storm-generated geostrophic flows. Five to thirty kilometres from shore, decimetre-bedded hummocky cross-stratified fine sandstone and mudstone record strongly oscillatory, wave-dominated flows whereas some gutter casts indicate shore-oblique, apparently mostly unidirectional geostrophic flows. Nearshore facies are dominated by swaley cross-stratified or intensely bioturbated clean fine sandstone, interpreted as recording, respectively, areas strongly and weakly affected by discharge from distributary mouths. Shoreface sandstones grade locally into river-mouth conglomerates and sandstones, including conglomerate channel-fills up to 15 m thick. Locally, brackish lagoonal shelly mudstones are present on the extreme western margin of the basin. There is no evidence for clinoform stratification, which indicates that the Kaskapau sea floor had extremely low relief, lacked a shelf-slope break, and was probably nowhere more than a few tens of metres deep. The absence of clinoforms probably indicates a long-term balance between rates of accommodation and sediment supply. Mud is interpreted to have been transported >250 km offshore in a sea-bed nepheloid layer, repeatedly re-suspended by storms. Fine-grained sediment accumulated up to a ‘mud accommodation envelope’, perhaps only 20 to 40 m deep. Continuous re-working of the sea floor by storms ensured that excess sediment was redistributed away from areas that had filled to the ‘accommodation envelope’, being deposited in areas of higher accommodation further down the transport path. The facies distributions and stratal geometry of the Kaskapau shelf strongly suggest that sedimentary facies, especially grain-size, were related to distance from shore, not to water depth. As a result, the ‘100 to >300 m’ depth interpreted from calcareous claystone facies for the more central parts of the Interior Seaway, might be a significant overestimate. [ABSTRACT FROM AUTHOR]

The main objectives of this in situ study were to evaluate the usefulness of an in situ bioassay to determine if downstream water bodies at the Key Lake and Rabbit Lake uranium operations (Saskatchewan, Canada) were toxic to Hyalella azteca and, if toxicity was observed, to differentiate between the contribution of surface water and sediment contamination to in situ toxicity. These objectives were achieved by performing 4-d in situ bioassays with laboratory-reared H. azteca confined in specially designed, paired, surface water and sediment exposure chambers. Results from the in situ bioassays revealed significant mortality, relative to the respective reference site, at the exposure sites at both Key Lake ( p ≤ 0.001) and Rabbit Lake ( p = 0.001). No statistical differences were found between survival in surface water and sediment exposure chambers at either Key Lake ( p = 0.232) or Rabbit Lake ( p = 0.072). This suggests that surface water (the common feature of both types of exposure chambers) was the primary cause of in situ mortality of H. azteca at both operations, although this relationship was stronger at Key Lake. At Key Lake, the primary cause of aquatic toxicity to H. azteca did not appear to be correlated with the variables measured in this study, but most likely with a pulse of organic mill-process chemicals released during the time of the in situ study—a transient event that was caused by a problem with the mill's solvent extraction process. The suspected cause of in situ toxicity to H. azteca at Rabbit Lake was high levels of uranium in surface water, sediment, and pore water. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we documented the Holocene history of a peat plateau at the arctic tree line in northern Québec using stratigraphic and macrofossil analyses to highlight the effects of geomorphic setting in peatland development. Paludification of the site began about 6800 cal yr BP. From 6390 to 4120 cal yr BP, the peatland experienced a series of flooding events. The location of the peatland in a depression bounded by two small lakes likely explains its sensitivity to runoff. The proximity of a large hill bordering the peatland to the south possibly favored the inflow of mineral-laden water. The onset of permafrost aggradation in several parts of the peatland occurred after 3670 cal yr BP. Uplifting of the peatland surface caused by permafrost stopped the flooding. According to radiocarbon dating of the uppermost peat layers, permafrost distribution progressed from the east to the west of the peatland, indicating differential timing for the initiation of permafrost throughout the peatland. Most of the peatland was affected by permafrost growth during the Little Ice Age. Picea mariana macroremains at 6450 cal yr BP indicate that the species was present during the early stages of peatland development, which occurred soon after the sea regression. [Copyright &y& Elsevier]

Among the factors that make an impression on international travellers arriving in Canada is the role that nature plays in explaining the country and its inhabitants. Of course, the book deals with the concept of nature from an environmental point of view, and focuses on how to protect nature from pollution and global climate change. I The Nature of Canada i contributes to rethinking how wilderness, climate, and nation are complex, constructed concepts, and how cultural and physical dimensions are strongly intertwined. [Extracted from the article]

In northern Nunavik, orientation of ice-flow features and dispersal patterns of lithologic indicators suggest three major regional ice-flow phases. The oldest ice-flow phase is related to the buildup of an outflow centre, the Ungava centre, over the high plateaux located north of the Povungnituk Hills. During that event, probably of Early Wisconsinan age, ice flows towards the south and southeast carried Cape Smith Belt rock fragments over a maximum distance of 65 km. The second phase is characterized by ice flow mainly towards the north from an outflow ice centre located south of the studied area (Payne centre). The most recent ice-flow phase is related to the presence of the northern extension of the New-Quebec ice divide. From that northwest-trending ice divide extending between Ivujivik and Lake Nantais, ice was flowing outward on the peninsula. The orientation of most of the ice-flow features and dispersal patterns is associated with that last ice flow. North of the Cape Smith Belt, glacial transport was at least 70 km. In Hudson Strait, ice-flow and glacial transport data support the existence of an eastward flowing ice stream. [ABSTRACT FROM AUTHOR]

The results of this dendrogeomorphological study provide evidence of the active movemerit of Hilda rock glacier, a tongue,shaped rock glacier in the Columbia Icefield region of Banff National Park. Cross-sectional samples were cut from 44 detrital subalpine fir (Abies lasiocarpa (Hook.) Nutt.) and Engelmann spruce (Picea engelmannii Parry) boles killed and buried by debris spilling off the steep distal slope of the rock glacier. The sampies were crossdated using locally and regionally developed tree-ring chronologies, and were shown to have been killed between 1576 and 1999. Our resuits show that Hilda rock glacier has advanced at an average rate of 1.6 cm/year since the late 1790s, with limited evidence of similar rates of activity extending back to the mid-1570s. This rock glacier activity is believed to be linked to persistent periglacial processes that appear to be independent of the climatic forcing mechanisms known to influence glacier mass balances over the same interval. [ABSTRACT FROM AUTHOR]

Molluscs, sediment lithology, and published sub-bottom profiles are used to deduce sea levels, outline the influence of glacially induced crustal displacement, and reconstruct the paleoenvironment of the northeast Pacific late Quaternary coastline. Geo-spatial modelling shows subaerially exposed land that could have been inhabited by plants and animals, and also coastally migrating early North American peoples. Ice-free terrain, present by at least 13 790 ± 150 14C years BP, a land bridge, and edible molluscs are identified. Queen Charlotte Islands (QCI) late Pleistocene coastal paleogeography may assist in explaining the biogeography of many terrestrial plant and animal species along the broader northeastern Pacific margin and provide evidence for researchers seeking late Pleistocene – early Holocene glacial refugia. Late Pleistocene – early Holocene coastlines that are not drowned and that may harbour early archaeological sites are identified along the western QCI, where migrants probably first travelled and the westernmost British Columbia mainland, where the effects of glacial ice were reduced. [ABSTRACT FROM AUTHOR]

The Eureka River landslide of June 1990, at 50 Mm[sup 3] , is one of the largest historical landslides on the Interior Plains of Canada. It is one of seven large translational landslides to have occurred in the Peace River Lowlands within the last 65 years. Each landslide occurred in Quaternary sediments deposited within a preglacial valley. Each landslide formed a dam. The rupture surface of the Eureka River landslide in preglacial lacustrine sediment, 125 m below the Peace River Lowlands plains, extended beneath the river channel causing the channel to be elevated. The resulting landslide dam was over 20 m high, forming a lake exceeding 8 km in length. The river cut a new channel around the toe of the landslide, abandoning the prelandslide channel. As the new channel is free of armour, incision has been rapid. After 10 years, the dam now stands approximately 5 m high.Key words: landslide, landslide dam, Peace River, Alberta, preglacial valley, geomorphology.Le glissement de la rivière Eureka de juin 1990, ayant un volume de 50 Mm[sup 3] , est un des plus importants glissements historiques des Plaines intérieures du Canada. Il est un des sept grands glissements translationnels à s'être produits dans les Basses-Terres de la rivière Peace au cours des 65 dernières années. Chaque glissement s'est produit dans les sédiments du Quaternaire déposés dans une vallée préglaciaire. Chaque glissement forme un barrage. La surface de rupture du glissement de la rivière Eureka dans le sédiment lacustre préglaciaire, localisée à 125 m sous les plaines des Basses-Terres de la rivière Peace, s'étendait sous le canal de la rivière produisant un soulèvement du canal. Le barrage du glissement résultant avait plus de 20 m de hauteur, formant un lac excédant 8 km de longueur. La rivière s'est frayé un nouveau canal autour du pied du glissement, abandonnant le canal existant avant le glissement. Comme le nouveau canal était libre d'armature, l'entaille a été rapide. Après 10 ans, le barrage mesure maintenant environ 5 m de hauteur.Mots clés : glissement, barrage de glissement, rivière Peace, Alberta, vallée préglaciaire, géomorphologie.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Discusses the diversity of the physical environment of British Columbia. Remains of the Noble Five mill at Cody; Description of a lake house in Coldstream Valley; Different settlements and human landscapes.

Geomorphic evidence and optical ages from seven locations indicate that widespread dune activity occurred within the last 200 years in the Great Sand Hills region of southwestern Saskatchewan. Optical ages (n = 36) define an interval of dune activity bracketed by the earliest age of back ridges in the Seward sand hills (185 ± 8 years) and the average age of stabilized dune heads (about 105 years). During this interval, parabolic dunes were active in all areas studied. These ages indicate that the most recent interval of activity was initiated about AD 1800, and continued at a level higher than present for approximately 80 years. The most likely cause of dune activation was lower-than-average precipitation (relative to 1960–1991 values) through the 1700s, culminating in drought in the late 1700s, as evidenced in dendroclimatic records from the Cypress Hills and from the Rocky Mountain foothills. Dunes affected by such climatically induced regional activity require many decades to restabilize. Historical observations show that dunes in this area have been restabilizing throughout the 20th century. For the southern Canadian Prairies, a region with serious concerns about the implications of global warming, this study highlights the sensitivity of sand dunes to drought and cumulative moisture stress.Des preuves géomorphologiques et des âges optiques de sept emplacements indiquent qu'il y eut une activité généralisée des dunes au cours des 200 dernières années dans la région des Great Sand Hills du sud de la Saskatchewan. Des âges optiques (n = 36) définissent un intervalle d'activité des dunes encadré par l'âge de la plus précoce des chaînes arrière dans les collines de sable Seward (185 ± 8 ans) et l'âge moyen des crêtes de dunes stabilisées (environ 105 ans). Au cours de cet intervalle, des dunes paraboliques étaient actives dans toutes les régions étudiées. Ces âges indiquent que l'intervalle d'activité le plus récent a débuté vers AD 1800 et a continué à un niveau supérieur au niveau actuel pour environ 80 ans. La cause la plus probable d'activation des dunes était des précipitations inférieures à la moyenne (par rapport à 1960–1991) tout au cours des années 1700, culminant dans la sécheresse de la fin des années 1700, tel que démontré dans les données dendroclimatologiques provenant des collines Cyprès et des contreforts des Rocheuses. Des dunes affectées par une telle activité régionale induite par le climat ont besoin de plusieurs décennies pour se stabiliser de nouveau. Des observations historiques montrent que les dunes de cette région se sont stabilisées tout au cours du 20[sup e] siècle. Pour les Prairies canadiennes méridionales, une région pour laquelle le réchauffement planétaire pose de grandes inquiétudes, cette étude souligne la sensibilité des dunes de sable à la sécheresse et au stress hygrométrique cumulatif.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

This paper presents data on and discusses the degree of postglacial stability of the northern Canadian tree limit. Holocene climatic changes have been both directional and synchronous for this region, though deteriorations/ameliorations either (1) lagged from west to east, (2) were buffered by local geographic factors, or (3) were not registered in the fossil record owing to the inherent persistence of the vegetation at some sites. The present northern tree limit in eastern Canada is in equilibrium with the prevailing climate, with the tree populations successfully regenerating both sexually and vegetatively. These tree stands are still occupying their maximum Hypsithermal positions. In contrast, the tree limit, tree line, and intervening forest-tundra ecotone in central and western Canada are out of equilibrium with today's climate. These populations are not sexually regenerative and apparently became established during warmer climates where the tree line was north of its present position. As such, they are susceptible to destruction by further climatic deterioration or anthropogenic disruption. [ABSTRACT FROM AUTHOR]

Multivariate statistical analyses allow specification of pollen-climate transfer functions useful in studies of paleoclimate. Two previously published models, when applied to two documented sites in Canada's District of Keewatin, produce inconsistent reconstructions of mean July temperatures for themed- to late-Holocene (approximately the past 5,000 years). The discrepancy between the results arises from differences in the construction of the functions. Of particular importance are the choice of pollen taxa included, and the sample provenances and the geographical range of the modern pollen data. A new model is developed with all-possible subsets regression, with due regard to the assumptions of the general linear model. Linear relationships between taxa abundances and summer temperature are specified, and multivariate outliers are removed. The paleotemperature records produced by the model for the two sites are consistent with the general features of previously reported work, and are more nearly similar to each other than reconstructions produced by the earlier, less sophisticated, models. [ABSTRACT FROM AUTHOR]

Cirques in the southern Canadian Cordillera are most numerous at lowest elevations and best developed on the north and northeastern flanks of mountains. Cirques at the heads of major valleys are generally at higher elevation, and are larger in area than cirques along the sides of valleys. The elevation frequency distribution is different for various types of cirque. Cirques which are well below mean cirque elevation are large and are almost always oriented to the north and northeast. Cirques well above mean cirque elevation are small and independent of orientation. A model is proposed in which cirque morphometry varies in a vertical plane in relation to the position of the snowline, and in a horizontal plane in relation to orientation. [ABSTRACT FROM AUTHOR]

Cirque floors increase in altitude toward the drier eastern parts of the Cordillera in southern British Columbia and Alberta, in a similar manner to the contemporary glaciation limit. Cirque floors are 100 to 400 m below the contemporary snowline. The relatively slight difference in elevation between the contemporary and cirque snowlines may possibly be attributed to a local decline in precipitation which partly compensated for the drop in temperature at the time of cirque formation. [ABSTRACT FROM AUTHOR]

Discusses the trend-surface analysis of two drumlin fields near Guelph, Ontario. Suggestion that drumlin elongation and size decline toward the margins of the fields; Random disturbance of the pattern resulting from local factors as land slope and drift depth; Morphological characteristics displayed by drumlin fields related to the decline of ice velocity and thickness toward the margins of an ice sheet.

Analyzes the equation used to derive the flow velocity from antidune wavelength for open-channel conditions in cloridorme formations in Gaspe Peninsula, Quebec. Calculations based on the modified equation; Indications of a much higher flow velocity.

The purpose of this article is to investigate whether place is emerging in practice as a critical dimension in the development of Canadian rural regions. Recently, Jones and Paasi set regional researchers the task of better understanding how regions 'become'. In researching this question, we are particularly interested in the definition and expression of place-based identity as a mobilizing force for regionalism. Our findings suggest that, while identity plays a critical role in fostering regional development processes, it is either too emergent or actively resisted within our research sites to be a significant force for place-based regional development. [ABSTRACT FROM AUTHOR]

The article focuses on the hazardous effect of runaway iceberg to the ocean. The scientists are observing the iceberg that broke away from Ellesmere Island, Canada. They predicted that the iceberg could bring havoc in the Arctic Ocean. The scientists believed that warmer temperatures in the summer will break up the pack ice around it, sending off the iceberg on a hundred miles journey. This may threatened heavily trafficked oil and gas shipping routes and oil platforms. The iceberg is considered to be part of the Ayles ice shelf and one of the only six such shelves on the island until it was broken in 2005.

The article focuses on the study conducted by Anne Peslier and colleagues which examines the African Kaapvaal craton and determines that water is the key for the persistence of the continents Canada and South Africa.

The article reports on the breakup of the Ayles shelf off Ellesmere Island near northern Greenland. The collapse was noted by the Canadian Ice Service on satellite images on August 13, 2005. A team led by glaciologist Luke Copland of the University of Ottawa reveals that 87.1 square kilometers of ice calved off in less than an hour. Scientists say that a crack was found in the 4500-year-old shelf when pack ice melted away and moved rapidly offshore in several pieces. Its breakup caused the disappearance of a rare freshwater lake ecosystem.

This article discusses storm-watching vacation destinations. The Canadian island of Tofino is cited as a popular locale for those looking to experience ocean storms. The island, located off the west coast of Canada's Vancouver Island, features special storm-watching vacation packages for those interested in meteorology. The article also notes that a Canadian web site designed to track icebergs will launch in 2006 or 2007. The web site will track the movement of icebergs from early spring to late summer.