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A Field Examination of Climate-Permafrost Relations in Continuous and Discontinuous Permafrost of the Slave Geological Province by Kumari Catharine Karunaratne B.Sc, The University of Western Ontario, 2000 M.Sc, Carleton University, 2003 A thesis submitted to the Faculty of Graduate and Postdoctoral Affairs in partial fulfillment of the requirements for the degree of Doctor of Philosophy In Earth Sciences Carleton University Ottawa, Canada © 2011 Kumari Catharine Karunaratne Library and Archives Bibliotheque et 1*1 Canada Archives Canada Published Heritage Direction du Branch Patrimoine de Pedition 395 Wellington Street 395, rue Wellington Ottawa ON K1A 0N4 Ottawa ON K1A 0N4 Canada Canada Your file Votre reference ISBN: 978-0-494-81573-1 Our file Notre reference ISBN: 978-0-494-81573-1 NOTICE: AVIS: The author has granted a non L'auteur a accorde une licence non exclusive exclusive license allowing Library and permettant a la Bibliotheque et Archives Archives Canada to reproduce, Canada de reproduire, publier, archiver, publish, archive, preserve, conserve, sauvegarder, conserver, transmettre au public communicate to the public by par telecommunication ou par I'lnternet, preter, telecommunication or on the Internet, distribuer et vendre des theses partout dans le loan, distribute and sell theses monde, a des fins commerciales ou autres, sur worldwide, for commercial or non support microforme, papier, electronique et/ou commercial purposes, in microform, autres formats. paper, electronic and/or any other formats. The author retains copyright L'auteur conserve la propriete du droit d'auteur ownership and moral rights in this et des droits moraux qui protege cette these. Ni thesis. Neither the thesis nor la these ni des extraits substantiels de celle-ci substantial extracts from it may be ne doivent etre imprimes ou autrement printed or otherwise reproduced reproduits sans son autorisation. without the author's permission. In compliance with the Canadian Conformement a la loi canadienne sur la Privacy Act some supporting forms protection de la vie privee, quelques may have been removed from this formulaires secondaires ont ete enleves de thesis. cette these. While these forms may be included Bien que ces formulaires aient inclus dans in the document page count, their la pagination, il n'y aura aucun contenu removal does not represent any loss manquant. of content from the thesis. 1+1 Canada ABSTRACT Climate-permafrost relations were examined across treeline using field data from the Slave Geological Province. The surface and thermal offsets, parameterized in the TTOP model, were used as a framework for the investigation. Air, ground surface, and permafrost temperatures were measured for two years (2004-06) at 24 peatlands in three study areas near Yellowknife, Colomac, and Ekati, Northwest Territories. The Yellowknife and Colomac study areas lie south of treeline in the discontinuous permafrost zone, but Ekati lies north of treeline in the continuous permafrost zone. Surveys of vegetation, snow, and soil were conducted to assess the role of microclimate on the climate-permafrost relation. Air temperatures across the Slave Province were near climate normals (1971-2000) in the first year, and were 4 °C higher on an annual basis in the second year. South of treeline, the ground thermal regime was similar and did not respond to spatial or temporal changes in air temperature. North of treeline, surface and ground temperatures were considerably lower, and the climate-permafrost relation was stronger. Differences in climate-permafrost relations within the discontinuous permafrost zone, across treeline, and interannually resulted from differences in the duration of active-layer freezeback, when release of latent heat prevents substantial ground cooling. South of treeline, freezeback of the active layer was prolonged by thick snow covers, while north of treeline, where snow covers were thinner, freezeback was shorter and allowed the ground to cool for the majority of the winter. The variability of the surface offset south ii of treeline was controlled by total active-layer water, which is not easily estimated remotely, rather than snow. The thermal offset was controlled locally by changes in the thermal conductivity ratio (rk), and regionally by climate. To evaluate the thermal offset model, values of rk determined from soil samples were compared with values obtained directly from field temperature measurements. The model performed well under normal climate conditions, but only to the north where freezeback was short. The thermal offset model did not calculate ground temperatures accurately for wet active layers under thick snow covers, or for transient conditions regardless of moisture regime or permafrost temperature. iii DEDICATION This thesis is dedicated to my mother, Elizabeth Karunaratne ACKNOWLEDGEMENTS This PhD research has facilitated an important journey for me. I wish to express my gratitude to the people and organizations that have made this passage possible. Financial assistance for this endeavour was provided by: BHP Billiton and Indian and Northern Affairs Canada - Contaminated Sites Division (in-kind support), the Natural Sciences and Engineering Research Council of Canada through postgraduate scholarships and Chris Burn's Northern Research Chair, an Ontario Graduate Scholarship, and the Northern Scientific Training Program. Discussions with several people significantly improved this project. Antoni Lewkowicz provided essential comments on site selection. Ken Torrance was always helpful in the soil lab. Dan Riseborough was my TTOP Wikipedia, and his review of my final draft was most appreciated. My colleagues at the Geological Survey of Canada were very supportive, especially Caroline Duchsene who made the maps. I am indebted to my supervisor Chris Burn for introducing me to process-driven / partnership-based permafrost research, for his thoughtful suggestions, and for believing in me. Thank you Chris, I'm proud to have been your student. Significant results from this research concerning permafrost and treeline were dependent on field data collected at Ekati Diamond Mine and Colomac Mine. I am grateful to BHP Billiton for access to Ekati, especially Helen Butler whose excitement for industrial-based research was contagious. The work at Colomac was supported by Octavio Melo of Indian and Northern Affairs Canada - Contaminated Sites Division, and the employees of Tli Cho Logistics provided critical help and humour on the site. Numerous people assisted in the collection of field data. I would like to thank Jesse MacFarlane, Krystal Thompson, Beth Anne Fischer, and Elizabeth Karunaratne for their dedication to my field program and tolerating my perfectionism. Much appreciated camaraderie in Yellowknife included: Heather Scott & Julian Kanigan, Mike Palmer &Wendy Lahey, Donna Nash Alain & Dennis Alain, Nahum Lee & Zoe Posynick, Elsbeth & Regan Fielding, and Damian Panayi & Mindy Willet. Steve Kokelj was always available for field assistance, thoughtful discussions, and emotional support. I am grateful for his mentoring and my friendship with Shawne, Ella, and Makoa Kokelj. In the early years of this process, significant personal support was received from the Roberts family, Linda Advokaat, and Fionnuala Devine. Edith Dauphinais's hospitality through the hardest years will never be forgotten. In Peterborough, Beverly and Amy Smith were always there for me, Cousin Carol Winter provided much needed support, and Bernie Bauberger transformed the direction of my spiral. The final phase was considerably aided by PranaShanti, NLP Partners, Dr Jaworski, and Bryce Healey. Jan Creelman provided an office and belly-rubs to a certain husky. Andrew Panciuk offered meals, music, and mischief. Mike Wood bestowed much praise and points of reflection. Advice on fashion, statistics, and self-efficacy was graciously received from Logan Nealis. My co-travellers, Peter Morse and Pascale Roy- Leveillee, kept me company on this road and are right behind me. Several people have provided unwavering support throughout my journey. The little green dot that is Michelle Cote always responded regardless of where she resided. vi Marcus Ward was my Switzerland and continually dependable. Evan Seed checked in on the longest and shortest of days. Jen Buck provided humour as we climbed - YES! The view is considerably brighter these days! Sonja Zupanec lovingly took my phone calls during the loneliest times. Regardless, I always knew I could count on Dayanti Karunaratne - I'm so thankful we are parting with closeness. Special recognition is extended to Jane and Hudson for introducing me to Pamela Grassau and Beth Jackson. Pam, thank you for your generosity, particularly with respect to coffee. Beth, thank you for your affirmations, especially concerning butter. I experienced profound healing through attention, acceptance, appreciation, affection and allowing at Breezehill Ave, as will others. I could not have accomplished this without you two. You will be deeply missed. Finally, I wish to express my most sincere appreciation to my mother, Elizabeth Karunaratne, for her loving presence, authentic apologies, financial safety-net, drumlin lectures, and amazing enthusiasm for life. It is an honour to have such an unconventional mother - Thanks Mommy! vii TABLE OF CONTENTS ABSTRACT ii DEDICATION iv ACKNOWLEDGEMENTS V TABLE OF CONTENTS viii LIST OF TABLES xii LIST OF FIGURES xvi LIST OF ABBREVIATIONS xxiv Chapter One: Overview and Objectives 1 1.1 Introduction