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Variability of Sea Ice Drift Through Nares Strait, Nunavut, Canada

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Variability of Sea Ice Drift Through Nares Strait, Nunavut, Canada VARIABILITY OF SEA ICE DRIFT THROUGH NARES STRAIT, NUNAVUT, CANADA ASHLEY O’BRIEN A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE GRADUATE PROGRAM IN GEOGRAPHY YORK UNIVERSITY TORONTO, ONTARIO January 2019 ©Ashley O’Brien, 2019 Abstract One of the greatest indicators of climate change is the state of the Arctic sea ice cover, whose extent is declining at an unprecedented rate due to both melt of sea ice and advection out of the Arctic Ocean. Nares Strait is an important conduit for the export of sea ice from the Arctic Ocean to sub-Arctic seas. Buoy trajectories for 2009, 2010, 2011 and 2014 were analyzed to evaluate the drift of sea ice through Nares Strait. Wind and ice concentration data were correlated with drift speeds to evaluate their influence on sea ice drift in this region which showed generally weak to moderate correlation coefficients. Drift speeds were highly variable spatially, seasonally and interannually. Smith Sound had the most spatial variability and the fastest drift speed (45 km/d). Drift through late summer showed high variability. It is believed that internal ice stress and ocean stress must play an integral role in ice dynamics in the strait but could not be quantified here. Further observations are required to more comprehensively understand sea ice dynamics in Nares Strait. ii Dedication I dedicate this thesis work to my friends and family who have unconditionally supported me throughout this entire process. I love you. iii Acknowledgments I would like to thank my supervisor Dr. Christian Haas for his guidance, support and immense knowledge. It has been a pleasure to work and learn from you over the past years. I also want to thank my committee Dr. Kathy Young and Dr. Rick Bello. A special thank you goes to Dr. John Alec Casey and Dr. Anne Irvin for their invaluable guidance throughout this process. To the Arctic Antarctic Sea Ice Lab, which includes Marzena Marosz-Wantuch and Mojtaba Daneshvar for support. A sincere thank you to my friends and family who have unconditionally loved and supported me through this rollercoaster ride. I would not have stuck through it all without your words of tough love and support. The biggest thank you to my Mom and Dad for allowing me to peruse graduate studies and for sticking by my side through it all as well as all of your endless support throughout whatever endeavor I embark on. Finally, to Ernon for your endless love, support and patience with me. iv Table of Contents Abstract .......................................................................................................................................... ii Dedication ..................................................................................................................................... iii Acknowledgments ........................................................................................................................ iv List of Tables .............................................................................................................................. viii List of Figures ............................................................................................................................... ix List of Abbreviations ................................................................................................................. xiii Chapter 1 Introduction................................................................................................................. 1 1.0 Study Context ...................................................................................................................... 1 1.1 Research Questions and Objectives ................................................................................... 3 1.2 Structure of Thesis .............................................................................................................. 4 Chapter 2 Background and Literature Review ......................................................................... 5 2.0 Introduction ......................................................................................................................... 5 2.1 The Changing Arctic Sea Ice Regime ................................................................................ 5 2.2 Dynamics of Sea Ice............................................................................................................. 9 2.2.1 Sea Ice Drifting Buoys ............................................................................................................................... 11 2.2.2 Wind Driven Sea Ice Drift ......................................................................................................................... 13 2.2.3 Ocean Driven Sea Ice Drift ........................................................................................................................ 16 2.2.4 Other Components of Sea Ice Drift ............................................................................................................ 19 2.2.5 The Case of Compact Ice Drift .................................................................................................................. 21 2.2.5.1 Sea Ice Concentration Data through Ice Charts .................................................................................. 23 2.3 Sea Ice Export from the Arctic Ocean ............................................................................ 24 2.4 Sea Ice Drift through Nares Strait ................................................................................... 28 2.5 Summary ............................................................................................................................ 32 Chapter 3 Study Site, Data and Methods ................................................................................. 34 3.0 Introduction ....................................................................................................................... 34 3.1 Study Site ........................................................................................................................... 34 3.1.1 Geographic Sub-Regions of Nares Strait ................................................................................................... 37 3.1.2 Climatology of Nares Strait ....................................................................................................................... 38 3.2 Data ..................................................................................................................................... 40 3.2.1 Buoy Data .................................................................................................................................................. 41 3.2.2 Meteorological Data ................................................................................................................................... 43 3.2.3 Sea Ice Concentration Data ........................................................................................................................ 45 3.3 Methodology ...................................................................................................................... 45 3.3.1 Buoy Analysis ............................................................................................................................................ 46 3.3.2 Meteorological Analysis ............................................................................................................................ 49 3.3.3 Analysis of Sea Ice Charts ......................................................................................................................... 50 3.3.4 Correlation Analysis .................................................................................................................................. 52 v Chapter 4 Results ........................................................................................................................ 53 4.0 Introduction ....................................................................................................................... 53 4.1 Drift Direction ................................................................................................................... 53 4.1.1 Turning Angles .......................................................................................................................................... 59 4.2 Drift Speed ......................................................................................................................... 60 4.2.1 Robeson Channel ....................................................................................................................................... 64 4.2.2 Kennedy Channel ....................................................................................................................................... 65 4.2.3 Kane Basin ................................................................................................................................................. 66 4.2.4 Smith Sound ............................................................................................................................................... 67 4.3 Wind Speed and Direction ................................................................................................ 68 4.4 Sea Ice Concentration ....................................................................................................... 72 4.5 Regression Analysis ..........................................................................................................
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