NWT RESEARCH DATABASE

Regions: Inuvialuit Settlement Region

Tags: physical sciences, geology, climate change, hydrology, coastline

Objective(s): To improve knowledge of physical conditions in the coastal zone in order to help government agencies, corporations, and local residents understand, mitigate and reduce the impacts of natural changes and industrial or community development.

Project Description: The western Arctic coast is among the most rapidly changing coastlines in the world and one of the most sensitive to climate change. The objective is to improve knowledge of physical conditions in the coastal zone in order to help government agencies, corporations, and local residents understand, mitigate and reduce the impacts of natural changes and industrial or community development. Spring (April/May/June) Mainly consists of helicopter reconnaissance work over the outer Mackenzie Delta. Current, water and sediment samples will be taken at various channel mouths during this time period. Time lapse cameras will be installed on industry wellheads and current and water level gauges will be deployed at various locations in the nearhore zone. If logistics permit, the researcher will undertake a 2-3 day small-boat survey of the seabed immediately after the ice breaks up to measure the depth of seabed disturbance due to current and strudel scours. Prior to the break-up (late April) some drilling and augering will take place in the winter and will employ hand tools and recovery of temperature data loggers from various previously drilled 10 m boreholes at the mouth and nearshore zone of Middle Channel. Ground penetrating radar (GPR) surveys will be undertaken in April from the ice surface using sleds pulled by human. GPR surveys will be concentrated in the nearshore zone of the Mackenzie Delta. Ground penetrating radar is a geophysical method that uses radar pulses to image the subsurface. This non-destructive method uses electromagnetic radiation in the microwave band (UHF/VHF frequencies) of the radio spectrum, and detects the reflected signals from subsurface structures. Summer (June-August) Acoustic surveys will be undertaken in the open-water season during the months of June and August (before and after whaling season). All will use very low energy echosounders. Small boats up to 8 m in length will be the primary means of data collection during the open water season. Acoustic surveys will be concentrated in the nearshore zone. Spring break-up and summer camps will be small (2-4 people) and of short duration (less than 20 days) and will be supported by small boats and helicopter. High resolution GPS surveys will take place at a number of coastal locations throughout the Mackenzie Delta, and Richard Island area. Helicopter will be used as the primary means of transportation to and from each site. No more than a few hours will be spent at each site. The surveyor at each location will walk along the coastline recording positional data from a RTK-GPS system corrected to a local base station. Stationary instrumentation will be deployed on the seabed to record changes using non-invasive and passive measurements for periods lasting several days or several months. Each logger is battery operated and no greater than 12 cm in diameter and housed within stainless steel 1-2 m mounting frames. Loggers will be deployed in locations and at depths to pose no hazard to shipping or boat traffic. A buoy will be placed at each location while it is on the seabed. The project will use previously proven and approved methods only. Field surveys will be undertaken in consultation with HTCs in order to ensure the timing of surveys is compatible with local use of the land and water. 2010 Research time-table April15-June 15 2010 1. Recover/redeploy temperature loggers at various locations in the outer delta 2. Acquire ground penetrating radar data in the nearshore region of Middle Channel, and the Olivier Islands. 3. Measure under ice currents at various locations throughout the delta 4. Deploy water level sensors on ice along Middle Channel distributary and in the nearshore zone (approx 2 m water depth). 5. Collect grab and shallow sediment cores beneath the ice. 6. Continue Epoch GPS surveys at various locations in the Mackenzie Delta 7. Install time-lapse cameras at industry well heads 8. Collect sediment and water samples at various times during the breakup period. 9. Measure under ice currents at various locations throughout the delta 10. Helicopter reconnaissance of breakup flooding and strudel formation 11. Measure flood extent and depth 12. Recover cameras, water-level gauges and current meters 13. Conduct bathymetric survey of strudel scour locations offshore from the mouth of Middle Channel (south of Garry Island in 2-3 m water depth) (August 1-31) 1. RTK-GPS of various coastal survey sites throughout the delta and Yukon coast. 2. Perform bathymetric surveys in the nearshore region from 1-5 m water depths (between Garry Island and the Olivier Islands). 3. Deploy and recover wave, current, salinity and optical backscatter sensors in the nearshore region of the Mackenzie delta. 4. Continue Epoch GPS surveys at various locations in the Mackenzie Delta On-site consultation and results reporting has been undertaken in all communities and to the IGC and the FJMC by Don Forbes and Steve Solomon at various times over the past five years. This consultation will occur annually prior to initiation of field programs. Donald Forbes will be available to present past results and future project plans to the local communities of Aklavik, Tuktoyaktuk and Inuvik in late Feruary/March 2010. Steve Solomon has participated in the ESRF meetings held in Tuktoyaktuk in February. The fieldwork for this study will be conducted from March 17, 2010 to September 20, 2010.