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1.
Parks Canada began the Northern Satellite Monitoring Program in 1997, with the objective of tracking large‐scale vegetation variation in Canadian ecosystems and helping land managers to develop appropriate management practices in response to climate change. Under this program, a sequence of 10‐day composite Advanced Very High Resolution Radiometer (AVHRR)‐derived Normalized Difference Vegetation Index (NDVI) data from 1985 to 2007 was examined to study seasonal and inter‐annual relationships between vegetation and climate data over Canadian ecosystems using statistical and wavelet analysis. Statistical analysis showed that temperature was the principal driver for seasonal variability in greenness, explaining more than 70 percent of seasonal variation in vegetation for most Canadian ecozones. In comparison with temperature, the relationships between NDVI and precipitation were weaker but still significant. Maximum annual NDVI showed increasing trends in Canadian ecozones during the study period, although increasing rates were spatially heterogeneous. Wavelet analysis confirmed that inter‐annual variation in NDVI was different at two ecozones in Canada. NDVI variation in the Northern Arctic was significant at scales of 3–4 years from 1997 to 2001, which was associated with temperature and precipitation variation. Comparatively, NDVI variation in the Boreal Shield was significant at scales of 5–8 years from 1991 to 1999, but did not correspond with climate variation.  相似文献   

2.
Spurred by the literature on climate change and its calls for undertaking holistic research that more fully integrates the work of biophysical and social scientists, this article responds to the question: To what extent has climate change research in Canada embraced and been guided by the theories and tenets associated with interdisciplinarity and to what extent have integrated approaches been sensitive to cross‐cultural perspectives? It provides an overview of some of the epistemological issues raised in the interdisciplinarity literature that particularly impact research development and design. Furthermore, since much of the climate change literature that claims to be integrated or interdisciplinary draws from Indigenous Knowledge (IK), additional insights are provided from this perspective. The article develops a framework that can be used to undertake and/or evaluate research in a way that acknowledges “upstream” epistemological issues. The framework is then used to evaluate a comprehensive database (n = 282) of Canadian climate change articles. It is argued that an interdisciplinary approach adds a critical voice to the literature on integrated climate change research and is valuable because of its focus on epistemology and methodology. The article advocates the creation of a space for inter‐epistemological acknowledgement in which the academy develops an ethos of self‐reflection, while simultaneously respecting and integrating parallel knowledge frameworks, such as IK.  相似文献   

3.
Scientists advise limiting global warming to 1.5°C with substantial actions by 2030. Our viewpoint argues that climate response strategies in Canada have underemphasized and underestimated the potential contribution deep energy retrofits can make to greenhouse gas (GHG) emissions reductions, leading to inadequate responses in the building sector, and that Canada can (and should) be ambitious with building retrofits over the next decade. GHG savings from building retrofits can be realized more quickly than GHG reductions from other sectors, and either deliver net cost savings or are cost‐effective when compared to other mitigation measures. Retrofits can also provide social and economic benefits, such as improved health and comfort, and lower energy costs. This paper reviews energy use and building retrofits in Canada and argues the following should be implemented: (1) focus innovation on deep energy retrofit processes, not singular retrofit actions; (2) maximize both social and environmental benefits; (3) improve data gathering and availability for analysis and delivery; (4) innovate for a process of decisions and to avoid “dropouts” during the retrofit process; and (5) focus innovation on business models that maximize benefits.  相似文献   

4.
5.
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   

6.
This article examines residential mobility for seniors 65 years of age and older in Canada using census data from 1961–2006. We addressed three questions. First, have seniors been increasingly likely to change their residential location within Canada or alternatively become increasingly likely to age‐in‐place? Second, has the in‐migration of seniors to Canada from other countries become more pronounced over the years? Third, does the residential mobility of seniors vary by age and sex? We used census data to calculate the percentages of seniors who changed their residence in the five‐year periods prior to each of the 1961–2006 censuses and the percentages of seniors who moved in the previous year for the 1991–2006 censuses. We calculated the percentages of seniors making local moves, longer distance moves within the same province, moves from one province to another, and moves to Canada from another country. We found that rates of residential mobility for seniors tended to increase in the 1961–1981 period but have been lower and relatively consistent from 1986–2006. We found no evidence to suggest a pattern of sustained increase in residential mobility of seniors. We conclude that Canadian seniors tend to age‐in‐place and that when seniors do change residence, the likelihood of residential mobility decreases with the distance of the move and decreases with age. Nevertheless, the likelihood of changing residence may increase for seniors 75+ years of age who need assistance and are at risk of institutionalization. We found that senior women were more likely to change residence locally than senior men. Finally, we found that from 1961 to 2006 between 0.8 percent and 1.4 percent of seniors had migrated to Canada in the five years prior to each census from other countries and that this pattern has fluctuated over the past half century with no clear trend.  相似文献   

7.
Freeze‐thaw cycles are most common at the beginning or near the end of the winter season. These cycles have various effects on the ecosystems of Eastern Canada, affecting both biotic and abiotic components of temperate cold environments. Using air temperature minima and maxima from four meteorological stations close to Québec City, we determined the frequency of daily freeze‐thaw cycles for the last 30 years. The results show no significant increase in the number of freeze‐thaw cycles despite a small increase in air temperature. Polynomial curves describing the relationship between mean air temperatures and the number of freeze‐thaw cycles were calculated. Based on these equations and anticipating a climate change scenario, we projected future freeze‐thaw cycles. Assuming a 5 °C increase in mean air temperatures by 2100, we estimated that the number of days with a freeze‐thaw cycle could increase by approximately 20 days per winter. The increase in the number of such cycles will be concentrated during the coldest months of the winter (January and February).  相似文献   

8.
The uneven distribution of environmental hazards across space and in vulnerable populations reflects underlying societal inequities. Fragmented research has led to gaps in comprehensive understanding of and action on environmental health inequities in Canada and there is a need to gain a better picture of the research landscape in order to integrate future research. This paper provides an initial assessment of the state of the environmental health research field as specifically focused on vulnerable populations in Canada. We present a meta‐narrative literature review to identify under‐integrated areas of knowledge across disciplinary fields. Through systematic searching and categorization, we assess the abstracts of a total of 308 studies focused on the past 30 years of Canadian environmental health inequity research in order to describe temporal, geographical, contextual and epistemological patterns. The results reveal that there has been significant growth in Canadian research documenting the uneven distributions and impacts of environmental hazards across locations and populations since the 1990s, but its focus has been uneven. Notably, there is a lack of research aimed at integrating evidence‐based and policy‐relevant evaluation of environmental health inequities and how they are created and sustained. Areas for future research are recommended including more interdisciplinary, multimethod and preventive approaches to resolve the environmental burden placed on vulnerable populations and to promote environmental health equity.  相似文献   

9.
Starting from an econometric model of local employment growth, applied to Canada (1971–2001), residuals—relative to model predictions—are analyzed over time and over space, in turn allowing us to draw a distinction between general explanatory variables and factors of a more local, cyclical or accidental nature. The model's explanatory power grows over time, founded on variables such as urban size, market access and industrial structure, allowing us to conclude that local employment growth in Canada follows an increasingly geographically predictable pattern. However, an examination of the residuals reveals more localized processes. Growth volatility is most manifest in Alberta and British Columbia, home to the most erratic local economies. Emerging patterns are visible in the last period, most notably the underperformance of Northern Ontario and of non‐metropolitan communities between Windsor and Québec City, lying along the Great Lakes and the Saint Lawrence. The over‐performance—compared to model predictions — of small and mid‐sized towns in south‐eastern Québec can, on the other hand, be interpreted as a sign of truly local social processes, generally associated with a particularly dynamic local entrepreneurial class.  相似文献   

10.
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   

11.
Diminishing returns and advances in telecommunications have prompted large video game firms to seek new locations, outsource production, and develop niche studios, including on Canada's East Coast. In this paper, we examine emerging occupational cultures and trace the origins and evolution of video game production in Canada's Atlantic provinces—a critical yet peripheral space economy in the gaming sector. Our findings are drawn from 30 interviews with gameworkers, studio managers, government officials, and other industry experts. We find this industry to be driven by the confluence of three major factors: (i) provincial governments have supported video game development as a strategic industry via financial incentives; (ii) firms are benefiting from a return migration effect and are repatriating Atlantic Canadian talent from media hubs by selling “home,” work‐life balance, and an alternative to the punishing gamework culture associated with Silicon Valley; and (iii) post‐secondary institutions in the region have improved their talent pipelines through computer science, digital media, and video game development programs.  相似文献   

12.
This article compares the political representation of visible minorities in Canada and the United States, focusing on differences in federal redistribution (redistricting) practices and constituency composition. Although the two countries both use territorially‐based electoral systems, they operate under different legal standards and institutional environments for the creation of ridings (districts). In the US, redistricting is a highly political process, yet must respect strict population equality standards. Litigation over redistricting is common, and courts adjudicate voting and representation under a constitutional system enforcing strong individual rights. In contrast, Canada's redistribution process is relatively nonpartisan, permits large population variances among ridings, places more emphasis on community rights, and is seldom subject to extensive court challenges. Despite these differences, the two countries exhibit striking similarities in the overall level of visible minority representation relative to population share. Conversely, Canada's population inequalities among ridings create a systematic disadvantage for visible minorities. Political attention to visible minority representation is stronger in the US, but the means to achieve it are constrained both by the judicial limits on group representation and the constitutional limits on the use of racial identity. Canada has a framework for political representation that could easily accommodate significant visible minority representation but lacks the political imperative to use it, in part because doing so would run counter to Canada's multicultural image of these groups as immigrants rather than as non‐white minorities.  相似文献   

13.
Interregional trade between Canada and the United States has undergone significant change since the inception of free trade. However, the magnitude of that change for the different regions in Canada and the United States has not been properly identified because of a lack of an appropriate measure. This paper introduces the concept of a quasi‐point and employs a spatial point pattern test to measure the degree of change in the interregional trade of Canadian provinces and US states, with an emphasis of that change on Ontario. It is found that the degree of change in the interregional trade flows is related to the degree of change in the provincial tariff rates.  相似文献   

14.
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   

15.
Fatal avalanche accidents in Québec (Canada) 1825 to 2009 Archival research, coroner's investigations, and newspaper searches reveal the occurrence of 43 deadly snow avalanches in Québec since 1825. Historical records indicate 73 fatalities and more than 50 injuries. Sixty percent of the victims were younger than 20 years old. More than 50 percent of the victims (38 fatalities in 12 incidents) were inside or near a residential building, usually their home, mainly in the cities of Québec and Lévis. The second‐most deadly category is recreational activities, with over 24 deaths in 20 accidents. Most of these deadly incidents occurred on very short slopes (<70 metres of relief) outside mountainous areas. Only five fatalities were related to backcountry recreational activities in highlands. The inventory of avalanche‐threatened areas has never been completed in the Province of Québec and it is likely that avalanche‐prone areas are more widespread than previously thought.  相似文献   

16.
Numerous anthropogenic stressors have impacted the region surrounding Sudbury, Ontario, leading to pronounced vegetation and landscape change. Few long‐term records exist to understand the nature or timing of this change. We use pollen analysis from radiometrically dated sediments of Clearwater Lake to compare pre‐ and post‐settlement vegetation. Beginning ~1850 CE, the record shows major shifts in forest composition, coincident with settlement and the beginnings of lumbering. These changes are unprecedented for the past ~5000 years, and consist of increases in diversity and abundance of deciduous tree taxa and herbaceous disturbance indicators. While evidence of mining appears as early as 1900 CE, little effect is seen in the pollen record until ~1930 CE, when sedimentation rates increased and acidification of the lake also began. At this time, further increases in palynological disturbance indicators and minimum sediment organic matter levels indicate the period of maximum vegetation loss. As a result of reduced emissions since the 1970s, water quality began to improve in Clearwater Lake and there are some decreases in the abundances of shade‐intolerant disturbance indicators in the pollen record. However, the fact that the pollen assemblages do not resemble those prior to 1850 suggests lasting vegetation changes.  相似文献   

17.
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   

18.
Environmental decision support systems (EDSS) are designed to assist natural resource managers and stakeholders to assess problems and select options for change. EDSS that combine community engagement in developing future scenarios with computer‐based land use planning and modelling tools are widely used internationally. However, these EDSS are often not used after the research and development phase. To best understand why the EDSS are not being used in the long term, the end users of the EDSS should be consulted—a perspective that is lacking in the literature. The research reported here presents the perspectives of stakeholders involved in a community climate change adaptation project in western Canada. Evidence from the community suggests that this project was successful in instigating change. However, the EDSS was not used after the project's end. Our findings indicate that, from the end users’ perspective, the project could have had much greater and sustained success had there been ongoing engagement and communication with them, particularly in the form of continued support for the use of EDSS after the development project.  相似文献   

19.
ABSTRACT

This paper examines how Canadian political science portrays Atlantic Canada, along with some of the consequences of persistent misrepresentations. I first explore traditional portrayals of Atlantic Canada as well as arguments challenging those conceptions, demonstrating that it is no longer appropriate to treat Atlantic Canada as primarily defined by either economic processes or common political culture. I then survey the Canadian Journal of Political Science, Canadian Public Administration and Canadian Public Policy to determine the extent to which discussions of Atlantic Canada still, (a) emphasize economic phenomena, and (b) assume a common Atlantic political culture. I find that, while political scientists are now less likely to study the region in terms of economic phenomena, they still perpetuate outdated depictions of Atlantic political culture. This tendency results in a certain degree of methodological imprecision and reinforces problematic assumptions about Atlantic political life.  相似文献   

20.
Zoos and aquariums are responding to the worldwide biodiversity crisis through major conservation initiatives like captive breeding for assurance populations and reintroduction programs. These institutions also fundraise, offer education programs, and provide critical research on biodiversity. Through a case study inside three accredited Canadian zoos, this paper illustrates that zoos and their staff members are being incorporated into many official species‐at‐risk recovery efforts on provincial, federal, and international levels. Specifically, the zoos studied are involved in every stage of the recovery process, from providing valuable research and habitat analyses, to captive breeding animals for reintroduction, to writing recovery strategies and creating recovery policy for multiple jurisdictional levels. Zoo staff indicate that zoos are uniquely suited to conservation because zoos have space, expertise, apolitical status, and the ability to connect with the public. Overall, the paper suggests that zoos can significantly contribute to species‐at‐risk protection and recovery in Canada and beyond.  相似文献   

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