Update on Hydrology Research at Scotty Creek, NWT (Bill Quinton)
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Update on Hydrology Research at Scotty Creek, NWT (Bill Quinton)
Canadian Excellence Update on Hydrology Research at Scotty Creek, NWT Changing Cold Regions Network, 2nd Annual General Meeting, Wilfrid Laurier University, 20-22 October, 2014. M. Braverman, J. Baltzer, A. Berg, R. Connon, J. Craig, L. Freeman, J. Gordon, E. Haugton, M. Hayashi, M. Helbig, A. McManus, A. Mohammed, B. Persaud, R. Schincario, O. Sonnentag, L. Stone, S. VanOpstal, P. Rahimzadeh, T. Veness, A. Verma Wilfrid Laurier University Waterloo, Canada annual runoff (mm) 400 300 200 ?? Birch Jean-Marie Blackstone Scotty 100 0 1970 1980 1990 2000 2010 Lower Liard River Valley Mackenzie Basin Continuous (> 90%) Discontinuous (50-90%) Discontinuous (10-50%) Isolated patches (< 10%) No permafrost What is driving the rise in basin runoff ? Expanding runoff contributing areas 300 m Primary Areas always 300 m never always 300 m never sometimes always 300 m Routing of Precipitation Inputs Cross-sectional view of a bog cascade - Primary runoff areas route moisture directly to the channel fen - Each bog has it’s own ‘bogshed’ (i.e. runoff contributing area) - Ephemeral channels connect flat bogs and drain into the channel fen, creating a “bog cascade” Flow through the bog cascade is dependent on the depression storage capacity in each bog. If the storage capacity of a bog is not satisfied this bog will not transmit moisture further down the cascade - Isolated bogsheds never contribute to flow Gauging Discharge: Secondary Source Areas b) a) c) Gauging at one of three channels that drainthat out drain of the peatGaugingdischarge discharge at one of three channels out plateau and into the channel of the complex peat-plateau complex andfen into the channel fen a) Rating curve calculated with instantaneous measurements a) Rating curve calculated with instantaneous b) Hydrograph for snowmelt period (May) measurements c) Flume box used to channel flow b) c) Hydrograph for snowmelt period (May) Flume box used to channel flow Three channels drain the plateau-bog Three channels the plateaucomplex into thedrain channel fen. Total bog complex intocomplex the channel fen. runoff from this in May Total complex 2013 runoff was 52from mm.this Basin runoffinfor May 52 mm, mm. indicating Basin runoff May 2013 2013 was was 44 for was are 44 mm, indicating thatMay bog 2013 cascades capable of that bog cascades are capable transmitting sufficient moistureof transmitting appreciable moisture during periods of high connectivity. during periods of high connectivity. Other insights on cascades: Wetland Ecotone: Seasonal thaw & permafrost thaw processes: Channel Fen Permafrost Plateau 0.1 0.2 0.3 0.4 0.5 0.6 elevation above fen (m) Flat Bog distance along shore (m) 6 5 4 3 2 1 0 0 1 2 3 4 distance into plateau (m) 5 Seasonal thaw & permafrost thaw processes: Channel Fen Permafrost Plateau Flat Bog Climate chamber experiments: no mulch mulch Department of Earth Sciences Seismic Lines: Short circuiting 1969 1943 5 km Thermal Channels 0m Bog 200 100 Fen 5m 7.5 m Fen Bog m 0 2.4 Depth to frost table along seismic line: May – July Thermosyphons: ? Spatio-temporal variability of GHG fluxes Footprint of eddy covariance measurements Footprint model:Kljun et al. 2004 Land cover & LIDAR: Chasmer et al. 2014 50 km Flux contribution during the growing season 2013 How widely does the permafrost thawinduced land cover change observed at Scotty occur over the region? e.g. NDVI trends. Top image shows the distribution of positive and negative trend pixels over the southern part of the Taiga Plains; the lower image shows those pixels that exhibit statistically significant trends. 2014 Field Season - Never a dull moment… Interdisciplinary fire studies: Not Burned Burned Runoff processes and pathways
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