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Assessing Glacier Mass Balances from Small Tropical Glaciers to The Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2007 Assessment of Glacier Mass Balances from Small Tropical Glaciers to the Large Ice Sheet of Greenland Todd Hayden Albert Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] THE FLORIDA STATE UNIVERSITY COLLEGE OF SOCIAL SCIENCES ASSESSMENT OF GLACIER MASS BALANCES FROM SMALL TROPICAL GLACIERS TO THE LARGE ICE SHEET OF GREENLAND By TODD H. ALBERT A Dissertation submitted to the Department of Geography in partial fulfilment of the requirements for the degree of Doctor of Philosophy Degree Awarded: Spring Semester, 2007 Copyright © 2007 Todd H. Albert All Rights Reserved The members of the Committee approve the dissertation of Todd H. Albert defended on March 23, 2007. ______________________________ Jim Elsner Professor Directing Dissertation ______________________________ J. Anthony Stallins Professor Co-Directing Dissertation ______________________________ Henry Fuelberg Outside Committee Member ______________________________ Xiaojun Yang Committee Member The Office of Graduate Studies has verified and approved the above named committee members. ii To my sister, who knew nothing about my topic, but everything about my struggle. iii ACKNOWLEDGMENTS Countless people have helped me along the way in some way or another. While I can’t possibly acknowledge everyone who helped me complete this project, I will highlight some of the most important ones. First, I must begin with my wife, who has struggled through this process along with me, shared my frustrations, and probably felt like a single parent at many times. I could never have accomplished all I have without her help and support. My children, Sage and Noah, both helped by being supportive and understanding when Daddy had to work instead of play. This work owes much to their patience and flexibility. Luckily for me, support from my family extends far beyond the walls of my home. From my aunt and uncle who continually gave support and advise, to my cousins who understood the difficulties I faced, everyone was there when I needed a shoulder or ear. My parents are the true heros of this story, instilling me with a sense of the great importance and value of education. They are my true inspiration. My sister, Jennifer, to whom this work is dedicated, has helped me through the hardest parts of this Ph.D. She and I shared in the untimely loss of our mother. She also completed her doctoral degree while working and having two kids of her own. She always understood the struggles I was facing, even if she had no clue about the science I was studying. Her best motivation came when she described the feeling of being finished, that feeling of being able to sit on the couch and do nothing without feeling guilty about not working. Looking forward to that feeling helped keep me on track even in my darkest hours. Even my in-laws, Linda and Jay, provided tremendous support and motivation. I never would have started on this track, however, were it not for some of the great iv teachers and professors that I met along the way. The first teacher who had a great influence on me was my 12th grade English teacher, Mrs. Hurley. She helped me see value in my writing and taught me that teachers can be your friend. In college, it was in Ellen Martin’s Introductory Geology class that I first learned about ice cores and about Ellen Mosley-Thompson and Lonnie Thompson. Having met Peter Waylen, Micheal Binford, Joann Mossa, and Cesar Caviedes, I had already decided that being a Geography professor was the life for me. Mike Binford, in particular, helped me to see just how cool Geography could be and the many great places it could take you. He also showed me the best way to teach a GIS or Remote Sensing class. Pete Waylen taught me that there is always time for your students, a lesson that was strongly reinforced by Lonnie Thompson later on. Ellen and Lonnie taught me much about the environment, the interconnected nature of the Earth system, and how to be a scientist. They also turned me on to the Quelccaya Ice Cap, a large focus of my research today. In Colorado, Jason Box, Nicholas Cullen, and Sandy Starkweather paved the way and taught me to conduct field work and taught me how to make it as a Ph.D. student. I owe a great debt of thanks to Jason for taking me under his wing and helping me become a field researcher and Greenland specialist. Koni Steffen gave me tremendous opportunities to conduct field research and turned me on to the Greenland Ice Sheet, a second focus of my research. Tad Pfeffer taught me more about snow and ice than I ever imagined there was to know. Roger Barry is a walking reference library of climate research. He sets high standards of what one person can learn and accomplish. Tom Chase taught me to be critical of every piece of science I encounter. Mark Williams taught me to clearly delineate my research while still listening to good music. Peter Blanken helped me to strike a balance between research, teaching, advising, and parenting. At Florida State, I could never thank Tony Stallins enough for his tremendous support and the work he put in to helping my edit my final draft. Jim Elsner helped me with everything from my statistics to my disc golf game while modeling how to drive my own children to do their best. He always had a quick answer to my frequently emailed questions. Xiaojun Yang gave me great encouragement to finish and helped build my self-worth. Henry Fuelberg also was a great asset as the outside member of my committee. v Finally, I must acknowledge the tremendous support I have always gotten from my friends, both life-long and new, and from the communities I have lived in and been a part of. Most recently, the Cornerstone Learning Community, where I taught for three years, has offered much love and support throughout. I thank you all! vi TABLE OF CONTENTS List of Figures ........................................ ...................... viii List of Tables ......................................... ....................... ix List of Acronyms and Abbreviations . ............... x Abstract ............................................ ....................... xii I. INTRODUCTION ...................................... .....................1 II. BACKGROUND ....................................... ...................15 III. RECENT HISTORY OF DEGLACIATION ON THE TROPICAL QUELCCAYA ICE CAP, PERU . 31 IV. MEASURING MASS BALANCE ON THE GREENLAND ICE SHEET . 51 V. MODELING MASS BALANCE ON ICE SHEETS . 70 VI. SUMMARY AND FUTURE WORK . 114 REFERENCES ......................................... 117 BIOGRAPHICAL SKETCH ................................. 142 vii LIST OF FIGURES 1.1 Base map of Peru . ..................6 1.2 Map of Greenland Automatic Weather Station network . 8 1.3 Annotated diagram of Smart Stake . .............9 1.4 Photograph of servicing Automatic Weather Station by helicopter . 9 1.5 Photograph of Swiss Camp in 1991 . 10 1.6 Map of Pâkitsoq Ablation Region, Greenland . 11 1.7 Photograph of refrozen meltwater ponds in Greenland . 13 3.1 Satellite image of the Quelccaya Ice Cap and its location in Peru . 34 3.2 Satellite-derived ice-extent history for the Quelccaya Ice Cap . 44 3.3 Map of the spatial pattern of retreat on the Quelccaya Ice Cap from 1962-2001 . 46 4.1 3-D map of the Pâkitsoq region and entire elevation profile for Greenland . 58 4.2 Scatterplot of measured density profiles and calculated water equivalent depths . 61 4.3 Annotated surface height record for JAR2, a typical ablation zone site . 64 4.4 Greenland station mass balance histories arranged by increasing elevation. 66 4.5 Elevation profile of mean mass balance components for Greenland . 67 5.1 Diagram of the time and space domains of influences on ice sheet mass balance . 71 5.2 Mean monthly PDDs for ablation zone sites . 77 5.3 A flowchart of the SNTHERM model operation . 81 5.4 Measured versus modeled surface lowering using various ice densities . 84 5.5 Measured versus modeled mean hourly surface energy fluxes . 86 5.6 Diagram depicting idealized layers in a melting snow pack . 96 5.7 General cases of idealized snow surface profile considered in the SOSIM model . 100 5.8 Partial surface height record for JAR 2 with model time domain highlighted . 107 5.9 SOSIM model output for Test Case 1, JAR 2 2001 . 108 5.10 Comparison of modeled ablation in Case 1 between SOSIM and other models . 109 5.11 SOSIM model output for Test Case 2, ETH 1999 . 110 5.12 Comparison of modeled ablation in Case 2 between SOSIM and other models . 111 viii LIST OF TABLES 3.1 List of satellite scenes used and their attributes . 41 3.2 Summary of results of ice-area determination and error estimates . 44 4.1 Manufacturers reported weather instrument accuracies . 61 5.1 Albedos of snow and ice surfaces . 91 5.2 Roughness lengths of snow and ice surfaces . 93 ix LIST OF ACRONYMS AND ABBREVIATIONS ASTER Advanced Spaceborne Thermal Emission and reflection Radiometer (remote sensor on the Terra satellite launched in 1999) AWS Automatic weather station (station designed to operate autonomously on a glacier and monitor the atmospheric pressure, radiation balance, profiles of temperature, wind speed, and humidity, and changes in surface height on a glacier; many stations transmit data hourly via satellite) BPRC Byrd Polar Research Center (cryospheric sciences center at The Ohio State University) CIRES Cooperative Institute for Research in Environmental Sciences; a joint
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