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This paper has examined the relative significance of uncertainty in future climate projections from a subset of the coupled model intercomparison project phase 5 (CMIP5) global climate models for the Prairie Provinces of western Canada. This was undertaken by determining: (a) the contribution of model and scenario uncertainty and natural variability to the total variance of these future projections, and (b) the timing of climate signal emergence from the background noise of natural climate variability. We examined future projections of mean temperature, precipitation and summer climate moisture index (CMI). In this region, natural climate variability plays an important role in future uncertainty until the end of this century, particularly for precipitation and to a lesser extent, summer CMI. Model uncertainty also contributes to total uncertainty for these variables throughout this century, while scenario uncertainty becomes more important towards the end of the century. For the region as a whole, significant climate change (i.e., signal/noise >2) occurs earliest for summer mean temperature, with median time of emergence around 2035 for the RCP8.5 radiative forcing scenario. Although the median precipitation signal emerges from the noise (i.e., signal/noise >1) around the 2070s in winter and the 2080s in spring, significant values do not occur in any season for this variable before 2100. For summer CMI, the median time of emergence for significant change is around 2085. At the grid scale, signal‐to‐noise ratios are significant for all seasons for mean surface air temperature, with earliest times of emergence occurring in summer. In contrast, the summer precipitation signal is not significant this century; for summer CMI, significant values are obtained in the eastern half of the region, occurring from about 2065 onwards. Median times of emergence are towards the end of the century for summer CMI in western Saskatchewan and in Alberta, although some areas of Alberta do not exhibit significant signals this century. [ABSTRACT FROM AUTHOR]

Despite an overwhelming scientific consensus that climate change poses severe risks to human and natural systems, many young Canadian adults do not view it as a major issue. We analyzed secondary science curricula in each province for their coverage of climate change according to six core topics: physical climate mechanisms (“It’s climate”), observed increase in temperature (“It’s warming”), anthropogenic causes of warming (“It’s us”), scientific consensus (“Experts agree”), negative consequences associated with warming (“It’s bad”), and the possibility for avoiding the worst effects (“We can fix it”). We found that learning objectives tend to focus on knowledge of the first three elements, with little or no emphasis on scientific consensus, climate change impacts, or ways to address the issue. The provinces of Saskatchewan and Ontario provide the most comprehensive standards for climate change education, while Nova Scotia and New Brunswick provide the least. We conducted interviews with individuals responsible for curriculum design in six different provinces to understand how curriculum documents are developed and whether political controversies influence the writing process. Interviewees described a process relying on input from professionals, institutions, and members of the public where curriculum developers made decisions independent of political concerns. In some cases, efforts to provide balance may have led to a focus on social controversy, contrary to overwhelming scientific consensus. Curriculum documents are the basis for teacher instruction and textbook content; aligning these documents with the best possible evidence can improve student learning and engage the next generation of Canadians on the critical issue of climate change. [ABSTRACT FROM AUTHOR]

International trade is often viewed as environmentally unproblematic, even beneficial. This article challenges this view, using new trade data from the Food and Agriculture Organization to document inefficiencies in global food trade and to question the prioritization of economics over environment. It can be difficult to identify the effects of macro-level phenomena, such as trade agreements and climate change, on people’s lives at the micro-level. This article uses qualitative research conducted with farm women in the Canadian prairies to illustrate the intersection of policy, climate change, and their gendered effects in everyday life. [ABSTRACT FROM PUBLISHER]

Reducing the large uncertainties in current estimates of CO sources and sinks at regional scales (10-10 km) is fundamental to improving our understanding of the terrestrial carbon cycle. Continuous high-precision CO concentration measurements on a tower within the planetary boundary layer contain information on regional carbon fluxes; however, its spatial representativeness is generally unknown. In this study, we developed a footprint model (Simple Analytical Footprint model based on Eulerian coordinates for scalar Concentration [SAFE-C]) and applied it to two CO concentration towers in central Canada: the East Trout Lake 106-m-tall tower (54°21′N, 104°59′W) and the Candle Lake 28-m-high tower (53°59′N, 105°07′W). Results show that the ETL tower's annual concentration footprints were around 10-10 km. The monthly footprint climatologies in summer were 1.5-2 times larger than in winter. The impacts of land surface carbon flux associated with heterogeneous distribution of vegetation types on the CO concentration measurements were different for the different heights, varied with a range of ±5 % to ±10 % among four heights. This study indicates that concentration footprint climatology analysis is important in interpreting the seasonal, annual and inter-annual variations of tower measured CO concentration data and is essential for comparing and scaling regional carbon flux estimates using top-down or bottom-up approaches. [ABSTRACT FROM AUTHOR]