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Threatened Arctic Lakes: Pressures from Climate Change and Resource Development Lindsey Witthaus Department of Environmental Engineering University of.

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Presentation on theme: "Threatened Arctic Lakes: Pressures from Climate Change and Resource Development Lindsey Witthaus Department of Environmental Engineering University of."— Presentation transcript:

1 Threatened Arctic Lakes: Pressures from Climate Change and Resource Development Lindsey Witthaus Department of Environmental Engineering University of Kansas Ashley Zung Department of Geography University of Kansas RESEARCH OBJECTIVES 1) summarize our current understanding of the mechanisms that drive thermokarst lake drainage by reviewing literature on the topic, from both western science and indigenous perspectives; 2) analyze the factors that contribute to lake drainage in an area of northwestern Canada and determine the potential for lake drainage in the region; and 3) evaluate current water resource policies in the Northwest Territories to determine how (or if) lakes and also traditional ecological knowledge are included in the policies. Mechanisms of Lake Drainage Potential Impacts of Oil and Gas Development Water Use Policy in the Northwest Territories BACKGROUND Lakes are a dominant feature of the arctic landscape in Northern Canada. There are over 45,000 thermokarst lakes in the Mackenzie Drainage Basin. Lakes are essential habitats. They serve as support systems for arctic food webs year-round, and provide key resources for human communities, such as freshwater, locations to hunt waterfowl during migratory seasons and to fish year-round, and navigation routes through the tundra to hunting camps Northwest Territories Water Act (1992) is the central water Mackenzie Valley Resource Management Act (1998) establishes a co-management framework for land and water regulations between First Nation Tribes. “in relation to waters when on or flowing through their first nation lands or waters adjacent to their first nation lands, the right to have the quality, quantity and rate of flow remain substantially unaltered by any person” (Mackenzie Valley Resource Management Act - S.C. 1998, c. 25 (Section 75)). Northwest Territories Northern Voices, Northern Waters: Water Stewardship Strategy integrates traditional knowledge systems into the NWT water management plans. Potential Impacts of Climate Change In this analysis, we focused on the effect of climate on permafrost degradation which can lead to thermokarst creation and lateral lake drainage, especially in ice-rich permafrost zones such as the Tuktoyaktuk Peninsula. Long-term climate data from stations at Tuktoyaktuk and Inuvik were obtained from Canada’s National Climate Archive at MAT and MWT at Tuktoyaktuk increased 4.3 C and 3.7 C, respectively. Increased MAT and MWT have been associated with increased permafrost thaw rates in modeling and observational studies across the Arctic. There was a lack of long-term data from Inuvik, and we cannot confidently comment on climatic trends at that location. MAP from was mm, varying from 89.1 mm to mm. The ten year running average of MAP confirms that precipitation decreased during the period of record. Average winter snow cover was 189.5, ranging from 75 cm in 1985 to cm in Ten year running averages show snow cover has also decreased. Decreased precipitation and snow thickness may retard permafrost degradation. Annual precipitation anomaly averaged mm from A positive annual precipitation anomaly could support lake area expansion; however, high inter-annual variability could still significantly alter surface water hydrology in the region. IPCC global climate projections anticipate 5°C warming in the arctic by Increased temperatures have the potential to alter permafrost and regional hydrology accelerating lake drainage. In order to assess the potential impact of human activity on lake drainage on the Tuktoyaktuk Peninsula, we focused the proposed Parsons Lake Gas Processing Facility and gathering pipeline. Assuming a 1 km area around the proposed pipeline route, and that the entire lease area near Parson’s Lake would be impacted, we estimated that at least 250 lakes in the area would be directly impacted by construction of the facility. We would expect many more to be impacted considering the interconnected nature of deranged drainage networks. The proposed 62,500 square meter gas conditioning facility north of Parsons Lake includes tanks, pump houses, living quarters, and a drilling pad. Extraction of natural gas and oil have caused land subsidence in the Arctic and warming of excess ground ice, causing further subsidence. Human constructs alter snow cover dynamics on the tundra, and construction and maintenance of the facility would disrupt vegetative cover further accelerating permafrost thaw, likely promoting permafrost degradation and lake drainage, and undoubtedly altering hydrological networks. Increased temperatures can cause permafrost melting and an influx of runoff into thermokarst lakes. The heat flux can both further thaw surrounding permafrost around and below the lake, resulting in larger lake areas and deeper talik. As the talik develops deeper below the lake it can eventually reach the groundwater table and hydraulic potential will cause subsurface drainage of the lake. Rising temperature can degrade permafrost and cause erosion and slumping of lake edges and stream channels. As stream channels open from the lake, rapid drainage can occur. Slumping and Declining Lake Levels William Paul (at Wilson’s Camp): “A tree has fallen in, really changing now. Really dried out the lake.” Interview conducted by Trevor Bennett September 12, Open Channel Partially Drains Lake William Paul: “Used to be a little water fall there, it was like a tap, now it’s wide open. This happened maybe in 2008? It really fell in. Interview conducted by Trevor Bennett September 12, 2010 Study Area Northern Canada Parson’s Lake Study Area Proposed Mackenzie Gas Project Pipeline and Facilities The Tuktoyaktuk Peninsula is located near the mouth of the Mackenzie River in the Northwest Territories, Canada. Arctic tundra here is underlain by the most ice-rich continuous permafrost in the Canadian Arctic (Lantuit & Pollard 2007). Pingos and arctic lakes dot the landscape. The Mackenzie Gas Project is a consortium of oil and gas companies, who have proposed construction of a 1,196 km pipeline system running through the Northwest Territories from the Arctic Ocean to northern Alberta (Imperial Oil, Limited 2003). The proposed Parsons Lake Gas Conditioning Facility would be built on the Arctic coastal plain, a landscape dominated by glaciofluvial and lacustrine sediments and numerous thermokarst lakes. Images from Inuvialuit Observations CONCLUSIONS Rising air temperature, increased snow cover, and negative precipitation anomalies increase permafrost thaw rates and may accelerate lake drainage in the Arctic. Human alteration of the landscape through vehicular traffic, removal of vegetation, construction of barriers, and other activities can further accelerate permafrost degradation and potentially lake drainage. Increasing MAT and MWT and construction of the gathering pipeline and gas processing facility around Parson’s Lake may significantly alter subsurface thermal regimes, leading to permafrost degradation. Possible subsidence and lake drainage of 250 lakes could significantly alter surface hydrology. Observations from northern Canadian indigenous communities indicate that rapid change is already occurring due to climate change and development. Further lake drainage and alteration of regional hydrology due to climate change and the Mackenzie Gas Project may be critically threaten to the livelihoods and culture of people who live there. While the Canadian Government may claim that they are powerless to reverse global climate change and the inevitable changes that will occur to water resources in First Nations communities, the Government does have an active role in approving development projects and natural resource extraction activities within its territories. The impacts of the Mackenzie Gas Project could be significant, seriously altering water and food resources, seemingly in contrast to the rights set forth in the Mackenzie Valley Resource Management Act. We have several concluding questions: 1.What will be the consequences of the Mackenzie Valley Project for the people living downstream of the project (i.e. the people living in the Inuvialuit Settlement Area)? 2.Will the right to unaltered water quality and quantity be enforced by the Canadian government? 3.If and when additional changes to water occur – will the Indigenous voices be heard? LAKE DRAINAGE IN GREENLAND Catastrophic lake drainage is also a problem in Greenland In warmer years supraglacial meltwater lakes are 3.5 times more likely to drain due to fractures in lake bed, which carry water to ice sheet bed (Liang et al. 2012) Diagram: University of Chicago arch.shtml arch.shtml Photo: Credit: ©James Balog


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