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A Late Holocene Reconstruction of Ocean Climate Variability in The The University of Maine DigitalCommons@UMaine Electronic Theses and Dissertations Fogler Library 2007 A Late Holocene Reconstruction of Ocean Climate Variability in the Gulf of Maine, USA, Based on Calibrated Isotope Records and Growth Histories from the Long-lived Ocean Quahog (Arctica islandica L.) Alan D. Wanamaker Follow this and additional works at: http://digitalcommons.library.umaine.edu/etd Part of the Climate Commons Recommended Citation Wanamaker, Alan D., "A Late Holocene Reconstruction of Ocean Climate Variability in the Gulf of Maine, USA, Based on Calibrated Isotope Records and Growth Histories from the Long-lived Ocean Quahog (Arctica islandica L.)" (2007). Electronic Theses and Dissertations. 101. http://digitalcommons.library.umaine.edu/etd/101 This Open-Access Dissertation 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. A LATE HOLOCENE RECONSTRUCTION OF OCEAN CLIMATE VARIABILITY IN THE GULF OF MAINE, USA, BASED ON CALIBRATED ISOTOPE RECORDS AND GROWTH HISTORIES FROM THE LONG-LIVED OCEAN QUAHOG (ARCTICA ISLANDICA L.) By Alan D. Wanamaker Jr. B.A. University of New Hampshire, 1997 M.A. University of New Hampshire, 1998 A THESIS Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy (in Earth Sciences) The Graduate School The University of Maine May, 2007 Advisory Committee: Karl J. Kreutz, Associate Professor, Department of Earth Sciences, and Climate Change Institute, Advisor Daniel F. Belknap, Professor, Department of Earth Sciences, School of Marine Sciences, and Climate Change Institute Harold W. Borns Jr., Professor Emeritus, Department of Earth Sciences, and Climate Change Institute (Honorary Director) Kirk A. Maasch, Professor, Department of Earth Sciences, and Climate Change Institute Neal R. Pettigrew, Associate Professor, School of Marine Sciences LIBRARY RIGHTS STATEMENT In presenting this thesis in partial fulfillment for an advanced degree at The University of Maine, I agree that the Library shall make it freely available for inspection. I further agree that permission for “fair use” copying of this thesis for scholarly purposes may be granted by the Librarian. It is understood that any copying or publication of this thesis for financial gain shall not be allowed without my written permission. Signature: Date: A LATE HOLOCENE RECONSTRUCTION OF OCEAN CLIMATE VARIABILITY IN THE GULF OF MAINE, USA, BASED ON CALIBRATED ISOTOPE RECORDS AND GROWTH HISTORIES FROM THE LONG-LIVED OCEAN QUAHOG (ARCTICA ISLANDICA L.) By Alan D. Wanamaker Jr. Thesis Advisor: Dr. Karl J. Kreutz An Abstract of the Thesis Presented in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy (in Earth Sciences) May, 2007 Understanding regional patterns of interannual to decadal-scale climate variability over the past 1000 years is critical for evaluating recently observed trends in atmosphere/ocean conditions, particularly in highly-productive ecosystems such as the Gulf of Maine (GOM) that are sensitive to minor changes in climate and/or changes in slope water input. To develop quantitative relationships between bivalve shell chemistry 18 (δ Oc) and growing conditions, aquaculture-based experiments were developed using Mytilus edulis collected in the GOM and Greenland. These experiments yielded a highly 18 accurate and precise paleothermometer [e.g., T °C = 16.28 (± 0.10) - 4.57 (± 0.15) {δ Oc 18 18 18 2 2 VPBD – δ Ow VSMOW} + 0.06 (± 0.06) {δ Oc VPBD – δ Ow VSMOW} ; r = 0.99; N= 323; p < 0.0001] for M. edulis, and the techniques were applied to the long-lived bivalve species Arctica islandica. To examine ocean variability in the Western GOM during the last millennium, a 142-year-old living A. islandica and three fossil A. islandica 14 shells (corrected CAMS = 1030 ± 78 AD; 1320 ± 45 AD; 1357 ± 40 AD) were collected for δ18O and growth increment analysis. The standardized annual growth index (SGI) of the modern shell is significantly correlated with continuous GOM plankton recorder data (1961 – 2003; Calanus finmarchicus; r2 = 0.55; p < 0.0001), and SGIs during the late Holocene contain significant periods of 2-6 years, suggesting that slope water variability coupled with North Atlantic Oscillation (NAO) dynamics is primarily responsible for productivity variability. Mean shell-derived isotopic changes were + 0.47 ‰ from 1000 AD to present, and likely reflect a 2 °C cooling caused by an increase in Labrador Current (LC) transport of ~ 0.7 Sv (1 Sv = 106 m3 s-1) and a corresponding decrease in Gulf Stream influence on GOM water temperatures during the past millennium. This hypothesis is consistent with modern observational relationships among the LC, GOM water temperatures, NAO, and Atlantic Multi-Decadal Oscillation (AMO). These results corroborate recent evidence of a large-scale cooling of slope waters and/or dynamical oceanographic changes outside the GOM during the Holocene, and suggest that a direct link exists between the GOM and Northwestern Atlantic. ACKNOWLEDGEMENTS This dissertation is dedicated to Jack and Jayna Wanamaker. May you both follow your passions and curiosities throughout life. To my wife Ellen, I thank you for supporting and encouraging me during these five years. Your selflessness and love is greatly appreciated. I thank my mother, Carol Vaughan, who taught me the value of hard work and dedication. I thank my primary advisor, Dr. Karl Kreutz, who provided fantastic opportunities, countless hours of guidance, and helpful feedback throughout the entire project. To the other members of my dissertation committee, Dr. Daniel Belknap, Dr. Harold Borns, Dr. Kirk Maasch, and Dr. Neal Pettigrew, I thank you for the essential guidance and feedback during this work. The work presented here is greatly improved because of your constructive criticism and encouragement. I thank Dr. Stephen Norton for his mentorship, and for inviting me to study at UMaine. I also thank Jeff Owen for encouraging me to come to UMaine. Dr. Bernd Schöne (University of Mainz) graciously hosted me at his lab in Germany, and taught me how to micromill and prepare Arctica islandica samples. Douglas “Cap” Introne spent a good portion of the last five years teaching me about mass spectrometry, and helping me run samples. Thank you, Cap. I thank Scott Feindel at the Darling Marine Center for his expertise, dedication, and help with all of the aquaculture work. I also thank family friends, Larry and Leah Marquis, for their support and inspiration to pursue my formal education. I thank Erich Osterberg for his friendship and many conversations about climate science. Bucky and Sue Owen warmly provided me with a place to stay for two years while I was commuting to UMaine. ii I am very grateful for the financial support that I received during my tenure as a graduate student. All of the research presented here was supported by the National Science Foundation (NSF ATM-0222553). Additional support from the Department of Earth Sciences and the Center for Science and Mathematics Education Research was provided via Graduate Assistantships. In addition, multiple grants from the Association of Graduate Students at UMaine provided travel support for research and conferences. The following acknowledgements refer to help and support I received for the research presented in chapters two through six. Chapter 2 is published in Geochemistry, Geophysics, Geosystems (2006, 7, Q09011,doi:10.1029/ 2005GC001189) with Karl J. Kreutz, Harold W. Borns Jr., Douglas S. Introne, Scott Feindel, and Bruce J. Barber. We thank Paul Rawson (University of Maine, School of Marine Sciences) for his advice on mussel cultivation, Nancy Raymond and Zachary von Hasseln (University of Maine students) for help maintaining the aquaculture systems, Timothy Miller (Darling Marine Center) for help with logistics and space, and Marty Yates for X-ray diffraction analysis (University of Maine, Earth Sciences). We also thank Mary Elliot and an anonymous reviewer for their insightful and constructive comments that improved this manuscript. Chapter 3 is in press in Paleoceanography (2007) with Karl J. Kreutz, Harold W. Borns Jr., Douglas S. Introne, Scott Feindel, Svend Funder, Paul D. Rawson, and Bruce J. Barber.We thank Robin Abbott and colleagues from VECO Polar Resources for travel and accommodations while in Kangerlussuaq, Greenland, Fartato Olsen for providing boating and bivalve collecting logistics in Sisimiut, Greenland, 109th Air National Guard (Albany, NY) for transportation to and from Greenland, Zachary von Hasseln (University of Maine) for aquaculture set-up and maintenance, Timothy Miller (Darling Marine iii Center) for help with logistics and space, Wendy Abdi for algal paste δ13C analysis (University of Ottawa, G.G. Hatch Isotope Laboratories), and Erin Fisher Owen for δ13C DIC/Salinity data (University of Maine). Bivalves collected in Greenland were transported into the USA and Maine with appropriate federal and state permits, in addition to written permission granted by the Denmark Directorate of Environment and Nature. We also thank David Dettman and David Gillikin for their insightful and constructive comments that greatly improved this manuscript. Chapter 5 is in review at the International Journal of Earth Sciences with Karl J. Kreutz, Bernd R. Schöne, Kirk A. Maasch, Andrew Pershing, Harold W. Borns Jr., Douglas S. Introne, and Scott Feindel. We thank Dan Belknap and
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