Science Meets Traditional Knowledge: Water and Climate in the Sahtu (Great Bear Lake) Region, Northwest Territories, Canada

In July 2005, several scientists from the Mackenzie GEWEX (Global Energy and Water Cycle Experiment) Study, known as MAGS, met with aboriginal people in Deline on the shore of Great Bear Lake to exchange information on climate and water in the region. Topics discussed pertained directly to the northern environment, and they included climate variability and change, wind, lightning, lake ice, lake level, and streamflow. The traditional knowledge shared by the residents is a rich source of local expertise about the landscape and climate systems of the Deline area, while the scientific knowledge provided by MAGS presents a scientific basis for many observed climate and water phenomena, particularly on a broad regional scale. Through cordial and open discussions, the meeting facilitated the sharing of traditional knowledge and scientific results. The meeting enhanced the potential for traditional knowledge to help direct and validate scientific investigations and for scientific knowledge to be used in conjunction with traditional knowledge to guide community decision making.En juillet 2005, plusieurs scientifiques de l’étude Mackenzie GEWEX (expérience internationale sur l’énergie et le cycle hydrologique), connue sous le nom de MAGS, ont rencontré les Autochtones de Deline, sur la côte du Grand lac de l’Ours dans le but d’échanger des données sur les conditions climatiques et hydrologiques de la région. Les sujets à l’étude se rapportaient directement à l’environnement nordique, plus précisément la variabilité et le changement climatiques, le vent, la foudre, la glace lacustre, le niveau des lacs et le débit des cours d’eau. Les connaissances traditionnelles des habitants de la région représentent une riche source d’expertise locale au sujet du paysage et des systèmes climatiques de la région de Deline, tandis que les connaissances scientifiques fournies par MAGS constituent une base scientifique pour de nombreux phénomènes climatiques et hydrologiques observés, surtout sur une vaste échelle régionale. Grâce à des discussions cordiales et ouvertes, cette réunion a donné lieu au partage de connaissances traditionnelles et de résultats scientifiques. Cette réunion a également permis d’accroître la possibilité que les connaissances traditionnelles aident à diriger et à valider les enquêtes scientifiques, et que les connaissances scientifiques soient employées de pair avec les connaissances traditionnelles pour favoriser la prise de décisions au sein de la collectivité

Seasonal Variations in the Limnology of Noell Lake in the Western Canadian Arctic Tracked by In Situ Observation Systems + Supplementary Appendix 1 (See Article Tools)

Research investigating climate-driven changes in northern lake ecosystems is complicated by a legacy of initiatives that have used sporadic observations, often confined to open-water seasons, to define the lake state. These observations have conventionally been lake water samples analyzed for a suite of physical and chemical parameters and are indicative of only the days or hours immediately before sampling. Monitoring approaches that sample a broader scope of limnological parameters over a continuous period are needed to augment existing strategies. A study of the seasonal changes to limnological parameters in Noell Lake was performed by analyzing continuous, hourly data collected from a series of automated and non-automated moorings over the period July 2012 to July 2013. Noell Lake was found to be strongly stratified throughout the open-water and under-ice seasons, with two prominent mixing periods in spring and fall. Processes of cryoconcentration and respiration intensified density-driven stratification while the lake is ice-covered, with the deep holes of Noell Lake becoming particularly saline and oxygen-depleted all year. Hypoxia was prevalent during the under-ice season because these physical and biogeochemical processes eliminated mixing from the lower lake depths while oxygen demand remained high. Use of continuous hourly monitoring facilitated improved understanding of the dynamical response of Noell Lake to atmospheric forcing.Les recherches sur les changements d’ordre climatique dans les écosystèmes lacustres nordiques sont compliquées par les incidences d’initiatives ayant recouru à des observations sporadiques, souvent restreintes aux saisons d’eaux libres, pour définir l’état des lacs. Habituellement, ces observations se sont traduites par l’analyse d’échantillons d’eau lacustre en fonction d’un ensemble de paramètres physiques et chimiques et par conséquent, elles ne sont représentatives que des jours ou des heures précédant immédiatement l’échantillonnage. Il y a lieu d’adopter des méthodes de surveillance qui permettent d’échantillonner de plus vastes paramètres limnologiques sur une période continue afin de rehausser les stratégies actuelles. L’étude des changements saisonniers à l’égard des paramètres limnologiques du lac Noell a été effectuée par le biais de l’analyse de données horaires et continues recueillies à partir d’une série d’amarrages automatisés et non automatisés pendant la période allant de juillet 2012 à juillet 2013. Cette étude a permis de déterminer que le lac Noell est fortement stratifié pendant les saisons d’eaux libres et d’englacement, et qu’il y a deux périodes de brassage importantes au printemps et à l’automne. Les processus de cryoconcentration et de respiration ont intensifié la stratification attribuable à la densité lorsque le lac est couvert de glace, les trous profonds du lac Noell devenant particulièrement salins et dépourvus d’oxygène pendant toute l’année. Pendant la saison d’englacement, l’hypoxie était répandue parce que ces processus physiques et biogéochimiques éliminaient le brassage dans les grandes profondeurs du lac alors que la demande en oxygène restait grande. Le recours à la surveillance horaire continue a permis de mieux comprendre la réponse dynamique du lac Noell au forçage atmosphérique

Ecological effects and causal synthesis of oil sands activity impacts on river ecosystems: water synthesis review

Abstract: Oil sands development in the lower Athabasca River watershed has raised considerable public and scientific concern regarding perceived effects on environmental health. To address this issue for tributaries and the mainstem of the Athabasca River in the Athabasca Oil Sands Region, the Water Component of the Joint Oil Sands Monitoring (JOSM) plan produced monitoring assessments for seven integrated themes: atmospheric deposition, tributary water quality, river mainstem water quality, groundwater quality and quantity, water quality and quantity modelling, benthic invertebrate condition, and fish health. Our review integrates and synthesizes the large and diverse datasets assembled in the seven JOSM theme assessments to: (a) evaluate possible environmental effects based on known sources and candidate proximal causes, and (b) determine the importance of cause-of-effect pathways related to contaminant, sediment and nutrient inputs. Although JOSM research identified ecological effects that appear to be associated with contaminant exposure, the source of this exposure is confounded by co-location of, and inability to differentiate between, oil sands operations (principally released by atmospheric emission) and inputs from the natural bitumen outcrops (e.g., erosional material transported by surface and groundwater flows). Nutrient enrichment from treated municipal sewage effluent was the dominant ecological effect observed for the mainstem Athabasca River, associated with increased fish size and changes in invertebrate assemblages, likely because this pollution source is discharged directly into the river. The ecological causal assessment method proved to be a useful tool for better understanding how stressor sources relate to ecological effects through candidate proximate causes. Factors that confound our ability to assess the ecological effects of oil sands development focus on our inability to adequately differentiate between contaminants supplied from natural and anthropogenic contaminant sources. Our causal synthesis identifies options for changes in future monitoring to better anticipate and detect degradation in the ecosystem health of the lower Athabasca River and its tributaries.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author