NWT RESEARCH DATABASE

Regions: Inuvialuit Settlement Region

Tags: physical sciences, arctic lakes, climate change, hydrology, lake ice, limnology

Objective(s): To develop a model that can be used to look at the vulnerability of small arctic lakes and ponds to changing climate.

Project Description: The overall objective of this study is to develop a model that can be used to look at the vulnerability of small arctic lakes and ponds to changing climate. Lake Ice Study: Lakes 5A, 5B and Noell Lake (MAP-2 of the original licence application) will be visited in mid-April to measure lake ice. Holes will be made in the ice using an ice corer. Ice thickness and composition will be determined by measuring and examining the ice cores. Through the holes in the ice water samples will be taken using small plastic bottles (removing no more than 3L of water from the lake). The water samples will be sent to laboratories to determine water properties. Sediment samples will also be taken from the lake bottom through the holes in the ice using a manual core sampler. Less than 9L of sediment will be removed. The sediment samples will be sent to laboratories to determine sediment characteristics. The field party and equipment will be transported to and from the study lakes by helicopter (one-day trips out of Inuvik) – the helicopter will land onto or near the lakes. If necessary, some travel might be by snowmobiles (using established snowmobile trails). Spring Melt: For 2-3 weeks during the spring melt period (late May/early June), the melting snow will be monitored, and resulting water flow to lakes 5A and 5B (MAP-2). The water flow to the lakes will be measured using conventional monitoring equipment (e.g. current meters; small portable weirs). Water samples from the flowing snowmelt water will be taken using small plastic bottles (30mL to 1L bottles). The water samples will be sent to laboratories to determine water properties. The field party and equipment will be transported to and from the study lakes by helicopter (one-day trips out of Inuvik) – the helicopter will land onto or near the lakes. Lake Studies: In 2011, research will be focused on Lakes 5A, 5B and Noell Lake (MAP-2 of the original licence application) and 6-12 other upland lakes/ponds selected strategically from the set of 60+ lakes north of Inuvik described above under "Specific Locations". Lakes 5A, 5B will be visited for the first time in June after the spring melt is complete and then once every week or two until mid-September. Noell Lake will be visited in June, and again in late-August or September prior to freeze-up. Half of the 6-12 additional lakes will be visited during a late June campaign; and the other half during a late August campaign. These lakes will be visited to obtain water samples using small plastic bottles (30mL to 1L bottles) – up to 3 litres of water will be removed from each lake per visit. The water samples will be sent to laboratories to determine water properties. Sediment samples from the lake bottom will be obtained from the same lakes using a small sampler – up to 9 L of sediment will be removed from the lake bottom per visit. The sediment samples will be sent to laboratories to determine sediment characteristics. Also, the lake water will be sampled for very small plant material, bacteria and insect larvae suspended in the lake water. These samples will be collected using a very small (20 cm) net, and sent to laboratories for analysis. For the lake study field work, the field party and equipment will be transported to and from the study lakes by helicopter (one-day trips out of Inuvik) – the helicopter will land onto or near the lakes. In some cases, a small inflatable boat will be used to collect samples from the lake. Detailed Topographical and Surface Cover Mapping: In 2010, the plans for detailed landsurface mapping (LiDAR and Hyperspectral Data) from a specialized aircraft had to be cancelled due to poor weather conditions during the time that the aircraft was available to us. During the summer of 2011 the researchers will try again to collect the topographical and surface cover information over the study area from the specialized aircraft, flying at an altitude of 1,500-1,600 meters which is above the minimum flight altitudes indicated in the EISC-Operating Guidelines and Procedures. Environmental Conditions: To monitor environmental conditions, a small temporary weather station will be set up at lake 5A and/or 5B (MAP-2) to measure air temperature, humidity, wind and precipitation. Attached to these automated stations will be instruments to measure lake water temperature, water level and other water properties. Permafrost depths at key locations near lakes 5A and 5B will be measured using permafrost probes (rods) and portable ground penetrating radar and sonar. Ground temperature at these permafrost sampling locations will be measured using temperature sensors. Some very small samples of permafrost ice will be collected and sent to laboratories to determine water properties. The researchers plan to hold annual community-based meetings and consultations in northern communities to inform local residents in the region of the nature and significance of the research and to provide updates on what they have learned (key findings) as the work progresses. They will also visit the schools to reach out to the youth. Information will also be made available through a project website, posters, brochures, fact sheets, etc. The fieldwork for this study will be conducted from April 1, 2011 to September 30, 2011.