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1.
In the context of global warming, changes in extreme weather and climate events are expected, particularly those associated with changes in temperature and precipitation regimes and those that will affect coastal areas. The main objectives of this study were to establish the number of extreme events that have occurred in northeastern New Brunswick, Canada in recent history, and to determine whether their occurrence has increased. By using archived regional newspapers and data from three meteorological stations in a national network, the frequency of extreme events in the study area was established for the time period 1950–2012. Of the 282 extreme weather events recorded in the newspaper archives, 70% were also identified in the meteorological time series analysis. The discrepancy might be explained by the synergistic effect of co‐occurring non‐extreme events, and increased vulnerability over time, resulting from more people and infrastructure being located in coastal hazard zones. The Mann Kendall and Pettitt statistical tests were used to identify trends and the presence of break points in the weather data time series. Results indicate a statistically significant increase in average temperatures and in the number of extreme events, such as extreme hot days, as well as an increase in total annual and extreme precipitation. A significant decrease in the number of frost‐free days and extreme cold days was also found, in addition to a decline in the number of dry days.  相似文献   
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The simulation of Sea-ice in a coarse resolution ocean general circulation model is examined in Hudson Bay and surrounding waters. Sea-ice distribution and duration compared well to climatological values, although ice thickness is undersimulated as it is in other modelling work. In Hudson Bay ice thickness variation was dominated by the atmospheric forcing as shown by the symmetric response of ice thickness to warming and cooling scenarios. Below ice heat fluxes play a more significant role in Foxe Basin and Baffin Bay where they mitigate air-ice heat loss by as much as 40 percent, thus limiting ice thickness and duration. Below ice heat flux reduces by 23 percent for the region of study (Hudson Bay, Foxe Basin, Baffin Bay, and Labrador Sea) for a global 3°C cooling and increases by 9 percent for a 3°C global warming. This asymmetric response is attributed to the ocean's asymmetric response to warming and cooling scenarios. In so much as Hudson Bay is dominated by atmospheric forcing rather than under ice heat as these results indicate, coarse resolution models may be useful in assessing the impact of change. However the necessary reconfiguration of the model grid render results from Foxe Basin and Hudson Strait less credible. On étudie la simulation de glace marine dans un modèle de circulation océanique générale à faible résolution dans la baie d'Hudson et dans les eaux avoisinantes. La distribution et la durée de la glace marine correspondent bien aux valeurs climatologiques, bien que l'épaisseur de la glace soit sous-simulée comme c'est le cas dans d'autres travaux de modélisation. Dans la baie d'Hudson, la variation de l'epaisseur de la glace est dominée par le forçage atmosphérique, comme on peut le voir d'après la réponse symétrique de l'épaisseur de la glace suivant les scénarios de réchauffement et de refroidissement. Les flux de chaleur sous la glace jouent un rôle plus important dans le bassin de Foxe et la baie Baffin, où ils permettent une réduction des pertes de chaleur air-glace allant jusqu'à 40 pour cent, limitant ainsi l'épaisseur de la glace et la durée. Le flux de chaleur sous la glace diminue de 23 pour cent dans la région étudiée (baie d'Hudson, bassin de Foxe, baie Baffin et mer du Labrador) pour un refroidissement global de 3C et augmente de 9 pour cent pour un réchauffement global de 3C. On attribue cette réponse asymétrique à la réponse asymétrique de l'océan aux scénarios de refroidissement et de réchauffement. Dans la mesure où, comme l'indiquent ces résultats, la baie d'Hudson est dominée par le forçage atmosphérique plutôt que par la chaleur sous la glace, des modèles à faible résolution peuvent être utiles pour évaluer l'impact des changements. Cependant, la reconfiguration nécessaire de la grille du modèle atténue la crédibilité des résultats obtenus dans le Bassin de Foxe et le détroit d'Hudson.  相似文献   
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The purpose of this paper is to provide a comparative assessment of the regional impacts and opportunities from climate change in Canada. The discussion draws extensively from a recently completed assessment of climate change impacts and adaptation in Canada, led by Environment Canada. The paper addresses impacts from three regional perspectives: expansion and northern shifts, impacts and opportunities in major regions, and ubiquitous impacts and opportunities. While some broad policy issues are evident, given the complexity of Canada's natural and human landscapes and the projected regional impacts, further research is needed before developing more targeted policy.
Cet article propose une évaluation comparative des effets des changements climatiques dans diverses régions du Canada - et des bénéfices qui pourront en résulter. L'étude se penche sur une évaluation récente d'Environnement Canada des bénéfices des changements climatiques et de l'adaptation à ces changements au Canada initiés par Environnement Canada. Nous divisons l'étude en trois parties: l'expansion et le déplacement vers le nord; les effets des changements climatiques et leurs bénéfices dans les principales régions du pays; les effets et les bénéfices des changements climatiques partout dans le pays. Bien que la nécessité de certaines politiques générales soit évidente, étant donné la complexité de la géographie humaine et naturelle du pays et les différents effets projetés dans les diverses régions du pays, il faudra faire des études approfondies avant de proposer des politiques plus spécifiques pour chaque région.  相似文献   
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Flood risk mapping allows for informed decision making regarding personal and community planning. Resistance to flood risk mapping can be driven by potential decline of property values. This paper explores resistance to flood risk mapping through the lens of climax thinking. Climax thinking is a novel theory guiding explorations of resistance to proposed land use changes. The aim of this study was to understand flood experiences, the presence of resistance to flood risk mapping, and whether climax thinking could help explain this resistance. To address this, surveys were administered to residents in the Nova Scotian towns of Liverpool and Bridgewater. We found that one third of respondents have experienced flooding, yet the majority have not seen a flood risk map, nor were they concerned about the potential impacts of flooding. Only one sixth of respondents exhibited resistance to flood risk mapping because of potential loss to property value. Dimensions of climax thinking were predictive of this resistance, specifically ignorance of an individual's own ability to adapt and inability to recognize the impact of their adaptation decisions on others, which together quadrupled the predictive power of the ordinal regression model. These insights can be applied to support the acceptance of flood risk mapping.  相似文献   
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POTENTIAL IMPACTS OF GLOBAL SEA-LEVEL RISE ON CANADIAN COASTS   总被引:3,自引:0,他引:3  
The sea-level rise that may result from global climate change is placed within the context of past and present sea-level changes on Canadian coasts. To assess future impact, a dimensionless index of sensitivity is determined. Coasts with low, moderate, and high sensitivity constitute 67%, 30%, and 3% of the total coastline, respectively. The most sensitive regions are: (1) several parts of the Maritime Provinces; (2) two areas of the British Columbia coast; and (3) a large part of the Beaufort Sea coast. Impacts in four regions - Bay of Fundy, Beaufort Sea, Fraser Delta, and Eastern Shore of Nova Scotia - are discussed in detail. It is argued that the societal response to changes in sea level should favour retreat and accommodation strategies.
Il est possible que les changements climatiques globaux provoqueront une élévation du niveau de la mer. Nous examinons ce scénario dans le contexte des changements passés et présents du niveau de la mer sur les côtes canadiennes. Pour évaluer l'impact de l'élévation prévue un indice non dimensionnel de vulnérabilité est déterminé. Les côtes à la vulnérabilité basse, modérée et élevée constituent, respectivement, 67%, 30%, et 3% de tout le littoral. Les régions les plus vulnérables sont: (1) plusieurs régions dans les provinces maritimes; (2) deux zones sur la côte de la Colombie britannique; et (3) la plupart de la côte de la mer de Beaufort. Nous discutons en détail les impacts dans quatre régions, soit la baie Fundy, la mer Beaufort, la delta du Fraser et la rivage dit 'Eastern Shore' de la Nouvelle-Écosse. Nous estimons que la réponse sociale aux changements du niveau de la mer devrait favoriser des stratégies de retraite et d'accommodement.  相似文献   
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I discuss the methodological challenges that research with Aboriginal women poses in historical geography, especially in Northern Canada. Drawing a parallel between historical geography and contemporary Northern studies, I explore how the predominance of climate change as a framework for funding Arctic research creates an environment where women's specific ways of knowing and connecting with the land are not adequately captured. A gender approach that is sensitive to the issues women face in their communities reveals that their experience of climate change, as well as the concerns they have about it, are inseparable from the other economic and social issues they face. I argue for the development of a feminist research agenda in the North that allows Aboriginal partners to locate themselves in the frameworks that are constructed for producing knowledge. At times letting the project ‘fail’ may be the surest way to enable the emergence of a locally‐driven agenda that addresses the present and future needs of Northern Aboriginal Peoples.  相似文献   
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Snow cover is often measured as snow‐water equivalent (SWE), which refers to the amount of water stored in a snow pack that would be available upon melting. Snow cover and SWE represent a source of local snow‐melt release, and are sensitive to regional and global atmospheric circulation, and changes in climate. Monitoring SWE using satellite‐based passive microwave radiometry has provided nearly three decades of continuous data for North America. The availability of spatially and temporally extensive SWE data enables a better understanding of the nature of space‐time trends in snow cover, changes in these trends and linking these trends to underlying landscape and terrain characteristics. To address these interests, we quantify the spatial pattern of SWE by applying a local measure of spatial autocorrelation to 25 years of mean February SWE derived from passive microwave retrievals. Using a method for characterizing the temporal trends in the spatial pattern of SWE, temporal trends and variability in spatial autocorrelation are quantified. Results indicate that within the Canadian Prairies, extreme values of SWE are becoming more spatially coherent, with potential impacts on water availability, and hazards such as flooding. These results also highlight the need for Canadian ecological management units that consider winter conditions.  相似文献   
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When a Canada‐wide daily climate time series, covering the period 1950–2010, became available, an opportunity arose to analyze the time series for trends of a variety of temperature indices. The 6,833 climate grid cells covering Alberta, each with an area of 10 km by 10 km, allowed the detailed mapping of 30 temperature indices across the province. From each time series, an annual series was computed, which then enabled trend analyses using the non‐parametric Mann‐Kendall and Sen Slope tests. New maps could be created at an unprecedented spatial resolution, and an associated website was developed to access all trends and changes between 1950 and 2010 for all grid cells at albertaclimaterecords.com . The confidence levels of some temperature trends exceed 99%, while others are below 80%. In Alberta's south, annual average temperatures have increased by 1°C to 2°C since the 1950s, but in Alberta's north the increase is 2°C to 4°C. The growing season has lengthened by between one and five weeks since the 1950s, while the number of frost days has declined. The most significant trends observed were increases in mean annual and winter temperatures, and declines in the number of days below ?20°C and heating degree days.  相似文献   
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