Can a Little Ice Age Climate Signal Be Detected in the Southern Alps of New Zealand?" (2001)
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The University of Maine DigitalCommons@UMaine Electronic Theses and Dissertations Fogler Library 8-2001 Can a little ice gea climate signal be detected in the southern alps of New Zealand? Jessica L. Black Follow this and additional works at: http://digitalcommons.library.umaine.edu/etd Part of the Climate Commons, Environmental Monitoring Commons, and the Glaciology Commons Recommended Citation Black, Jessica L., "Can a little ice age climate signal be detected in the southern alps of New Zealand?" (2001). Electronic Theses and Dissertations. 523. http://digitalcommons.library.umaine.edu/etd/523 This Open-Access Thesis is brought to you for free and open access by DigitalCommons@UMaine. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of DigitalCommons@UMaine. CAN A LITTLE ICE AGE CLIMATE SIGNAL BE DETECTED IN THE SOUTHERN ALPS OF NEW ZEALAND? BY Jessica L. Black B.S. University of St. Andrews, 1998 B.A. Wellesley College, 1999 A THESIS Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science (in Quaternary and Climate Studies) The Graduate School The University of Maine August, 2001 Advisory Committee: George H. Denton, Professor of Geological Sciences and Quaternary and Climate Studies, Advisor Thomas V. Lowell, Professor of Geology, University of Cincinnati Kirk A. Maasch, Associate Professor of Geological Sciences and Quaternary and Climate Studies William A. Halteman, Associate Professor of Mathematics and Statistics James Fastook, Professor of Computer Science and Quaternary and Climate Studies CAN A LITTLE ICE AGE CLIMATE SIGNAL BE DETECTED IN THE SOUTHERN ALPS OF NEW ZEALAND? By Jessica L. Black Thesis Advisor: Dr. George H. Denton An Abstract of the Thesis Presented in Partial Fulfillment of the Requirements for the Degree of Master of Science (in Quaternary and Climate Studies) August, 2001 The Little Ice Age (LIA) was a late Holocene interval of climate cooling registered in the North Atlantic region by expansion of alpine glaciers and sea ice (Grove, 1988). Here the LIA includes an early phase from about AD 1280 to AD 1390, along with a main phase from about AD 1556 to AD 1860, followed by warming and ice retreat (Holzhauser and Zumbiihl, 1999a). It has recently been demonstrated from records of North Atlantic ice-rafted debris that the LIA is the latest cooling episode in a pervasive 1500-year cycle of the climate system that may lie at the heart of abrupt climate change (Bond et al., 1999). This raises the question of whether the LIA climate signal is globally synchronous (implying atmospheric transfer of the climate signal) or out of phase between the polar hemispheres (implying ocean transfer of the climate signal by a bipolar seesaw of thennohaline circulation) (Broecker, 1998). New Zealand is ideally situated to address this problem as it is located on the opposite side of the planet from the North Atlantic region where the classic LIA signal is registered so clearly. Due to high precipitation and ablative activity gradients, glaciers in the Southern Alps of New Zealand respond to climate change on a decadal timescale (Chinn, 1996). Therefore, moraine sequences deposited during oscillations of these glaciers are ideal for determining the character of the LIA signal in this portion of the Southern Hemisphere. The chronology of the late Holocene moraine sequences fronting Hooker and Mueller Glaciers in the Southern Alps is controversial. Initial dating of these moraines from historical records, as well and from lichenometric and tree-ring analyses (Lawrence and Lawrence, 1965; Burrows, 1973), pointed to deposition in the LIA, indicating a global near-synchronous climate signal. In contrast, a subsequent chronology based on weathering rinds of surface clasts suggested that most of the late Holocene moraines antedate the LIA (Gellatly, 1984), implying lack of a classic LIA climate signal in this portion of the Southern Hemisphere. To resolve this dilemma, a new and detailed chronology of the Hooker and Mueller Holocene moraine systems was constructed in this study by using geomorphologic maps, historical records, and the FALL lichenometry technique. A major result of this study is that most of the Holocene moraines fronting Mueller and Hooker Glaciers were deposited during the main phase of the LIA as defined in the North Atlantic region. The glacier advances recorded by these moraines are about equivalent in age with those in the North Atlantic region. The magnitude and timing of the LIA climate signal is nearly the same in the two regions. The collapse of Hooker and Mueller Glaciers in the last 140 years is also approximately synchronous with retreat of glaciers in the North Atlantic region. Therefore, the LIA climate signal occurs in the atmosphere as far south as New Zealand, on the other side of the planet from the North Atlantic region. ACKNOWLEDGMENTS There are many people who have contributed to this thesis. Foremost, my advisor George Denton for his endless patience with my creative grammar, for his generous support throughout this incredible project, and for his guidance during my time in Maine. My committee members have all been very helpful and encouraging. Kirk Maasch and Tom Lowell provided much needed assistance for this thesis and offered valuable insights. Bill Halteman’s contribution to this thesis was exceptional - his experience with statistics, his gift for teaching, and his willingness to go beyond what was expected of him led to a significantly stronger thesis. Debbie and Nancy - this thesis could not have been finished without you both - thank you so much for your support. This thesis was funded by NOAA and the Lamont Consortium for Abrupt Climate Change. I thank my parents for always encouraging me to try, and then helping to support me along the way. My Aunt Veronica and her family provided a much needed refuge for me during my time in the east. They helped smooth out all the rough patches, and celebrate all the victories. My friends in Orono are the reason why my stay in Maine was so special. Thank you Robin and Nazife for being such special friends and always listening, Mike - you’re drawings are exceptional and have added so much to my thesis, Nate - the blinding moon of the geology department, Heather- I’ll eat ice cream anytime. Ben, Becky, Julia, Doug, Adam, Wendy - you’ve all been extraordinarily patient - thank you. I would also like to thank those that helped me in the final preparations - Nancy, Mom, Ethan, Robin, and Corinn - you are all incredible. .. 11 TABLE OF CONTENTS .. ACKNOWLEDGMENTS ............................................................................................. 11 LIST OF TABLES ........................................................................................................ v LIST OF FIGURES ...................................................................................................... vi I . Introduction ............................................................................................................ 1 The Problem .............................................................................................................. 1 The Strategy .............................................................................................................. 2 North Atlantic Type Region .................................................................................... 3 Swiss Glacier Record of the Little Ice Age ............................................................. 7 Little Ice Age .Early Phase (-AD 1280-1290 to 1390) ......................................... 7 Inter-Little Ice Age Warm Period (-AD 1390 to 1555).......................................... 8 Main Phase of Little Ice Age (-AD 1556 to 1850-1860)........................................ 8 New Zealand ........................................................................................................... 13 Mueller Valley ....................................................................................................... 20 Hooker Valley ....................................................................................................... 24 II . Previous Work ..................................................................................................... 28 Initial Studies of Holocene Moraines Fronting Hooker and Mueller Glaciers ..................................................................................................... 28 Recent Studies of Holocene Moraines Fronting Hooker and Mueller Glaciers ..................................................................................................... 30 III . Glacial Geomorphology .................................................................................... 33 Mueller Morphosequences .................................................................................... 34 Morphosequence M-A1 ......................................................................................... 34 Morphosequence M.A2 ......................................................................................... 35 Morphosequence M-B ........................................................................................... 35 Morphosequence M-C ........................................................................................... 37 Morphosequence M-D ........................................................................................... 38 Morphosequence M-E ..........................................................................................