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Surface energetics and snow ablation were examined during the 1999 snowmelt season in a mountain subarctic tundra valley in the Yukon Territory of Canada. Considerations of melt energetics at small scales were made with respect to the frame of reference of the sloping surface snowpack. During relatively warm and sunny conditions early in melt, snow ablation rates were dramatically higher on the south-facing slope and strongly reduced on the north-facing slope, compared to the valley bottom. Negative spatial covariances developed between maximum snow accumulation and ablation rate during early and middle melt, with the highest ablation rates occurring on slopes with the shallowest snowpacks. Atmospheric conditions were sufficiently well mixed across the valley that reference level air temperatures and humidity among the slopes were close to levels of measurement accuracy. However, under high levels of April insolation, notable differences in incoming solar radiation to varying slopes/aspects caused relatively larger differences in net radiation and surface temperature, which were progressively magnified as shrubs and soil became exposed during snow ablation. Under cloudier conditions later in melt, the south-facing snowpack had mostly ablated, vegetation was exposed at all sites, and ablation rates were virtually identical between the valley bottom and north-facing slope. Driven primarily by initial differences in insolation and snow accumulation, surface energy fluxes changed sign and magnitude over space, not only with insolation, vegetation cover, slope, and aspect, but also with the snow cover state and ground/vegetation exposure. Melt rate was, hence, controlled by both incoming energy and evolving and initial snow states. For these reasons, and because of the slope-based frame of reference necessary to precisely define the snowmelt energy balance, simple aggregate representations of melt in subarctic mountain environments that are based on averaged energy flux, snow state, and flat-plane conceptions may require substantive corrections that should be explored in modeling studies. [ABSTRACT FROM AUTHOR]

With increasing emphasis among health care providers and funders on patient-centered care, it follows that patients and their caregivers should be included when priorities for research are being established. This study sought to identify the most important unanswered questions about the management of kidney failure from the perspective of adult patients on or nearing dialysis, their caregivers, and the health care professionals who care for these patients. Research uncertainties were identified through a national Canadian survey of adult patients on or nearing dialysis, their caregivers, and health care professionals. Uncertainties were refined by a steering committee that included patients, caregivers, researchers, and clinicians to assemble a short-list of the top 30 uncertainties. Thirty-four people (11 patients; five caregivers; eight physicians; six nurses; and one social worker, pharmacist, physiotherapist, and dietitian each) from across Canada subsequently participated in a workshop to determine the top 10 research questions. In total, 1570 usable research uncertainties were received from 317 respondents to the survey. Among these, 259 unique uncertainties were identified; after ranking, these were reduced to a short-list of 30 uncertainties. During the in-person workshop, the top 10 research uncertainties were identified, which included questions about enhanced communication among patients and providers, dialysis modality options, itching, access to kidney transplantation, heart health, dietary restrictions, depression, and vascular access. These can be used alongside the results of other research priority-setting exercises to guide researchers in designing future studies and inform health care funders., (Copyright © 2014 by the American Society of Nephrology.)

The Northern Rivers Ecosystem Initiative (NREI) was established in the late 1990s to address important science questions resulting from previous studies undertaken by the Northern Rivers Basin Study (NRBS). This manuscript summarizes the results from a number of reports on hydrologic research conducted on the Peace-Athabasca-Slave river and lake systems. Specific concerns expressed by the NRBS and subsequent NREI focused on how these systems were being affected by climate change, flow regulation and land-use changes. Issues addressed in this report include: the fate of aquatic perched basins within the Peace-Athabasca Delta under historical and future climate trends; the sources of major floods that replenish these basins and how the frequency, magnitude and source areas of such events have changed over time; the synoptic weather patterns and atmospheric teleconnections that are responsible for the generation of major snowmelt runoff that drive major floods; the potential effect that climate and land-use changes might have on basin runoff and delta lake levels; the specific hydro-climatic conditions required to produce major ice-jam floods on the Peace River and how these may be altered by climate change; remote-sensing methods to document delta flooding and vegetation change; and the dual effect of climate and flow regulation on the water levels of Great Slave Lake and how these may affect other nearshore processes, particularly wind seiches, that influence flooding of the Slave River Delta. A review of the major findings and recommendations for future research concludes the report.