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Design storms (DS) that are determined from intensity-duration-frequency (IDF) relationships are required in many water resources engineering applications. Short duration DS are of particular importance in municipal applications. In this paper, linear trends were estimated for different combinations of durations and frequencies (return periods) of annual short-duration extreme rainfall. Numerical analysis was performed for 15 meteorological stations from the province of Ontario, Canada. The estimated magnitude (rate mm/h) and direction of trend (increasing, decreasing, or no trend) were estimated and then used to quantify the effect of trend on the frequency of design storms. Significant trends were detected for all durations. It was determined that due to the existence of trends (which might be attributed to climate change), the design storms of a given duration might occur more frequently in the future by approximately as much as 36 years depending on the duration and return period. [ABSTRACT FROM AUTHOR]

This paper presents a multidisciplinary modeling approach to quickly quantify climate change impacts on energy consumption, peak load, and load composition of residential and commercial buildings. This research focuses on addressing the impact of temperature changes on the building cooling load in ten major cities across the Western United States and Canada. Our results have shown that by the mid-century, building yearly energy consumption and peak load will increase in the Southwest. Moreover, the peak load months will spread out to not only the summer months but also spring and autumn months. The Pacific Northwest will experience more hot days in the summer months. The penetration levels of air-conditioning (a/c) systems in this region are likely to increase significantly over the years. As a result, some locations in the Pacific Northwest may be shifted from winter peaking to summer peaking. Overall, the Western U.S. grid may see more simultaneous peaks across the North and South in summer months. Increased cooling load will result in a significant increase in the motor load, which consumes more reactive power and requires stronger voltage support from the grid. This study suggests an increasing need for the industry to implement new technology to increase the efficiency of temperature-sensitive loads and apply proper protection and control to prevent possible adverse impacts of a/c motor loads. [ABSTRACT FROM AUTHOR]

Rising fuel prices and global warming are two major issues that concern people today. In this paper, the effect that the integration of the hybrid photovoltaic (PV)/wind-turbine generation can have on conservation of energy and reduction of greenhouse gases (GHGs) has been studied. Base-case energy demands were calculated using building energy simulation software and then the residential buildings were equipped with the PV/wind-turbine electricity generation devices. The results show that the integration of those equipments can reduce both cost of fuel and GHG emissions to a fair amount. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Climate change is already occurring in the Arctic and the Arctic Climate Impact Assessment recently concluded that future climate change could be devastating for Inuit. This paper characterises vulnerability to climate change in two Inuit communities in the Canadian territory of Nunavut, focusing on the resource harvesting sector. In both communities, Inuit have demonstrated significant adaptability in the face of current changes in climatic conditions. This adaptability is facilitated by traditional Inuit knowledge, strong social networks, flexibility in resource use, and institutional support. Changing Inuit livelihoods, however, have undermined certain aspects of adaptive capacity and have resulted in emerging vulnerabilities. Global and regional climate projections indicate that climatic conditions which currently pose risks are expected to be negatively affected by future climate change. These projections are not without precedent and analysis of current vulnerability and identification of adaptation constraints by Inuit in the two communities indicate the continued importance of traditional coping mechanisms. The ability to draw on these coping mechanisms in light of future climate change, however, will be unequal and the research indicates that young Inuit and those without access to economic resources, in particular, are vulnerable. [ABSTRACT FROM AUTHOR]

Recent studies have shown that ice duration in lakes and rivers over the Northern Hemisphere has decreased over the 19th and 20th centuries in response to global warming. However, lake ice trends have not been well documented in Canada. Because of its size, considerable variability may exist in both freeze‐up and break‐up dates across the country. In this paper, results of the analysis of recent trends (1951–2000) in freeze‐up and break‐up dates across Canada are presented. Trends toward earlier break‐up dates are observed for most lakes during the time periods of analysis which encompass the 1990s. Freeze‐up dates, on the other hand, show few significant trends and a low degree of temporal coherence when compared with break‐up dates. These results are compared with trends in autumn and spring 0 °C isotherm dates over the time period 1966–95. Similar spatial and temporal patterns are observed, with generally significant trends toward earlier springs/break‐up dates over most of western Canada and little change in isotherm and freeze‐up dates over the majority of the country in autumn. Strong correlations (r > 0·5) between 0 °C isotherm dates and freeze‐up/break‐up dates at many locations across the country reveal the high synchrony of these variables. These results are also consistent with more recent observations of other cryospheric and atmospheric variables that indicate, in particular, a general trend toward earlier springs in the latter part of the 20th century. The results of this study provide further evidence of the robustness of lake ice as a proxy indicator of climate variability and change. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study presents the results of a second-generation climate change assessment for three key ski regions of Quebéc incorporating snowmaking as a climate adaptation strategy. Potential economic ramifications for ski operators are assessed separately for the main revenue-generating period and shoulder seasons. The paper concludes that climate change does not pose a threat to the Quebéc ski industry under 2020s scenarios and that, while adequate snow base can be maintained with additional snowmaking under even the warmest scenario for the 2050s, the combined economic impact of lost revenue opportunities from a shortened ski season and increased snowmaking costs will likely prove prohibitive for some ski operators. [Copyright &y& Elsevier]

In many practical applications snow depth is known, but snow water equivalent (SWE) is needed as well. Measuring SWE takes ∼∼20 times as long as measuring depth, which in part is why depth measurements outnumber SWE measurements worldwide. Here a method of estimating snow bulk density is presented and then used to convert snow depth to SWE. The method is grounded in the fact that depth varies over a range that is many times greater than that of bulk density. Consequently, estimates derived from measured depths and modeled densities generally fall close to measured values of SWE. Knowledge of snow climate classes is used to improve the accuracy of the estimation procedure. A statistical model based on a Bayesian analysis of a set of 25 688 depth--density--SWE data collected in the United States, Canada, and Switzerland takes snow depth, day of the year, and the climate class of snow at a selected location from which it produces a local bulk density estimate. When converted to SWE and tested against two continental-scale datasets, 90%% of the computed SWE values fell within ±±8 cm of the measured values, with most estimates falling much closer. [ABSTRACT FROM AUTHOR]

Annual and seasonal trends in temperature, dewpoint, relative humidity, and specific humidity are presented for the period 1953–2005. The analysis uses hourly observations from 75 climatological stations across Canada. Data were examined for discontinuities due to changes in instruments and observing practice. It was found that the main discontinuity corresponds to the replacement of the psychrometer by the dewcel in the early 1970s, which created an artificial negative step in relative humidity and dewpoint at many locations. After accounting for these discontinuities, the results of trend analysis show evidence of an increase in air moisture content associated with the warming observed in the country. During winter and spring, the significant warming in the western and southern regions is accompanied by an increase in dewpoint and specific humidity and by a decrease in relative humidity; in summer, warming is observed in the southeast and it is associated with significant positive trends in dewpoint and specific humidity. Although there is no strong evidence of a greater nighttime warming in Canada over 1953–2005, the nighttime dewpoint and specific humidity trends are slightly larger than the daytime trends, especially during the spring and summer. [ABSTRACT FROM AUTHOR]

The article reports on near-surface-temperature lapse rates on the Prince of Wales Icefield in Ellesmere Island in Canada. In this study, screen temperatures were monitored from May 2001 to April 2003 in 25 sites in this location. It is posed that surface-temperature lapse rate in the region are systematically less than the free-air lapse rates that are commonly adopted for extrapolations of sea-level temperature to higher altitudes. Lastly, the low surface-temperature lapse rates and their systematic synoptic variability have essential implications for applications that involve downscaling of surface- or boundary-layer temperatures.

BACKGROUND: Canada has recognized that Aboriginal and northern communities in the country face unique challenges and that there is a need to expand the assessment of vulnerabilities to climate change to include these communities. Evidence suggests that Canada's North is already experiencing significant changes in its climate—changes that are having negative impacts on the lives of Aboriginal people living in these regions. Research on climate change and health impacts in northern Canada thus far has brought together Aboriginal community members, government representatives, and researchers and is charting new territory. METHODS AND RESULTS: In this article we review experiences from two projects that have taken a community-based dialogue approach to identifying and assessing the effects of and vulnerability to climate change and the impact on the health in two Inuit regions of the Canadian Arctic. CONCLUSIONS: The results of the two case projects that we present argue for a multi-stakeholder, participatory framework for assessment that supports the necessary analysis, understanding, and enhancement of capabilities of local areas to respond and adapt to the health impacts at the local level. [ABSTRACT FROM AUTHOR]

Hydrological response to climate change may alter the biogeochemical role that peatlands play in the global climate system, so an understanding of the nature and magnitude of this response is important. In 2002, the water table in a fen peatland near Quebec City was lowered by ∼20 cm (Experimental site), and hydrological response was measured compared to Control (no manipulation) and Drained (previously drained c. 1994) sites. Because of the draw-down, the surface in the Experimental pool decreased 5, 15 and 20 cm in the ridge, lawn and mat, respectively, increasing bulk density by ∼60% in the Experimental lawn. Hydraulic conductivity (K) generally decreased with depth and from Control (25–125 cm) 10-1 to 10-5 cm s-1 to Experimental (25–125 cm) 10-2 to 10-7 cm s-1 and to Drained (25–75 cm) 10-2 to 10-6 cm s-1. In similar topographic locations (ridge, lawn, mat), K trended Control > Experimental > Drained, usually by an order of magnitude at similar depths in similar topographic locations. Water table fluctuations in the Drained site averaged twice those of the Control site. The water table in the Control lawn remained at a stable depth relative to the surface (∼ - 1 cm) because the lawn peat floats with changes in water table position. However, the Drained lawn peat was more rigid because of the denser degraded peat, forcing the water to fluctuate relative to the surface and further enhancing peat decay and densification. This provides a positive feedback loop that could intensify further peat degradation, changing the carbon cycling dynamics. [ABSTRACT FROM AUTHOR]

The western Canadian Arctic is identified as an area of potentially significant global warming. Thawing permafrost, sea level rise, changing sea ice conditions and increased wave activity will result in accelerated rates of coastal erosion and thermokarst activity in areas of ice-rich permafrost. The Yukon Coastal Plain is widely recognized as one of the most ice-rich and thaw-sensitive areas in the Canadian Arctic. In particular, Herschel Island displays extensive coastal thermokarst. Retrogressive thaw slumps are a common thermokarst landform along the Herschel Island coast that have been increasing in both frequency and extent have in recent years due to increased thawing of massive ground ice and coastal erosion. The volume of sediment and ground ice eroded by retrogressive slump activity and the potential release of climate change related materials like organic carbon, carbon dioxide and methane are largely unknown. The remote setting of Herschel Island, and the Arctic in general, make direct observation of this type of erosion and the analysis of potential climate feedbacks extremely problematic. Remote sensing provides possibly the best solution to this problem. This study looks at two retrogressive thaw slumps located on the western shore of Herschel Island and using stereophotogrammetric methods attempts to (1) develop the first three-dimensional geomorphic analysis of this type of landform, and (2) provide an estimation of the volume of sediment/ ground ice eroded through back wasting thermokarst activity. Digital Elevation Models were extracted for the years 1952, 1970 and 2004 and validated using data collected in the field using Kinematic Differential Global Positioning System. Estimates of sediment volumes eroded from retrogressive thaw slumps were found to vary greatly. In one case the total volume of material lost for the 1970-2004 period was approximately 1 560 000m³. The estimated volume of sediment alone was 360 000m³. The temporal analysis of the DEMs suggest that second generation retrogressive thaw slump activity within the floor of a large polycyclic retrogressive thaw slump is possible. [ABSTRACT FROM AUTHOR]

Discusses the key requirements for implementation of the Kyoto Protocol to the United Nations Framework Convention on Climate Change (FCCC). Reference to how the Russian ratification of the treaty approved it along with the participation of 126 other countries; Indications that the U.S. and Australia will not take actions to ratify the agreement; Reference to how the rules of the agreement were rewritten at the Conferences of the Parties (COPs) of the Framework Convention in order to lower the costs for Canada, Japan, and Russia; Goals of a post-Kyoto framework which will focus on fundamental aspects of the science and economics of global climate change policy; Suggestion for industrialized to take initial steps to make emissions reductions on their own.

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