NWT RESEARCH DATABASE

Tags: physical sciences, active layer, climatology, greenhouse gases, atmospheric sciences, meteorology

Objective(s): To study how important greenhouse gases, carbon dioxide and methane, are exchanged between tundra surfaces and the atmosphere.

Project Description: The research goals are to study how important greenhouse gases, carbon dioxide and methane, are exchanged between tundra surfaces and the atmosphere. The researcher will measure these exchanges over various tundra types and relate them to environmental variables such as soil properties and weather, in hopes of understanding more about how future climate change will impact the land surface and how these impacts might influence the climate itself. This research is part of a long-term study of tundra-atmosphere interactions at Daring Lake. The primary platform for measuring the CO2 exchange is an eddy covariance tower, which has been established for the past several summers at an upland tundra site and in a wet sedge fen, and occasionally at a shrub site and at a new shrub site planned for 2010. These towers measure concentrations of the carbon gases in the atmosphere, wind and other meteorological variables, as well as soil temperatures and moisture. The tower equipment runs automatically and is visited a few times a week for data retrieval and maintenance. Daily (or weekly) measurements to vegetation growth and active layer depth (i.e., seasonal permafrost thawing) are made around each of the sites. There is virtually no disturbance of the surrounding tundra. As well, the researcher will measure CO2 from small (0.5 x 0.5 m) plots on various tundra communities using a manual chamber system. These measurements help us understand how the small-scale heterogeneity of the tundra vegetation influences our tower measurements. In addition, these measurements support the tower flux measurements, especially the new CH4 eddy flux tower equipment that was test run in 2009 and will be operated in future years. Some vegetation plots (5 per location) are manipulated by clipping the vegetation in order to measure the soil only component of the flux and to measure total biomass and leaf area index. These measurements are conducted weekly and confined to small patches of tundra not far from the towers. The measurements will take place between May and September, encompassing the summer growing period. Daring Lake Research Station hosts an annual 'Science Camp' for NWT high school students. Each year our group assists the camp by giving demonstrations of the research and tours of the sites and experiments. Members of our research group have been involved with this activity for the past several years and we look forward to participating in the future. Copies of any papers that result from our research will be forwarded to the Aurora Research Institute. We will gladly advance information to any communities or other groups wishing information on our research upon request. We will participate in the 2010 Daring Lake Science Camp. Although nothing is yet confirmed for 2010, we are happy to participate in organized public presentations of our research findings, and would be happy to make visits to communities for presentations and discussions concerning our research when invited and where possible. The fieldwork for this study will be conducted from May 6, 2010 to September 4, 2010.