Analysis of Coastal Erosion on Martha's Vineyard, Massachusetts: a Paraglacial Island Denise M
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University of Massachusetts Amherst ScholarWorks@UMass Amherst Masters Theses 1911 - February 2014 January 2008 Analysis of Coastal Erosion on Martha's Vineyard, Massachusetts: a Paraglacial Island Denise M. Brouillette-jacobson University of Massachusetts Amherst Follow this and additional works at: https://scholarworks.umass.edu/theses Brouillette-jacobson, Denise M., "Analysis of Coastal Erosion on Martha's Vineyard, Massachusetts: a aP raglacial Island" (2008). Masters Theses 1911 - February 2014. 176. Retrieved from https://scholarworks.umass.edu/theses/176 This thesis is brought to you for free and open access by ScholarWorks@UMass Amherst. It has been accepted for inclusion in Masters Theses 1911 - February 2014 by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. ANALYSIS OF COASTAL EROSION ON MARTHA’S VINEYARD, MASSACHUSETTS: A PARAGLACIAL ISLAND A Thesis Presented by DENISE BROUILLETTE-JACOBSON Submitted to the Graduate School of the University of Massachusetts Amherst in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE September 2008 Natural Resources Conservation © Copyright by Denise Brouillette-Jacobson 2008 All Rights Reserved ANALYSIS OF COASTAL EROSION ON MARTHA’S VINEYARD, MASSACHUSETTS: A PARAGLACIAL ISLAND A Thesis Presented by DENISE BROUILLETTE-JACOBSON Approved as to style and content by: ____________________________________ John T. Finn, Chair ____________________________________ Robin Harrington, Member ____________________________________ John Gerber, Member __________________________________________ Paul Fisette, Department Head, Department of Natural Resources Conservation DEDICATION All I can think about as I write this dedication to my loved ones is the song by The Shirelles called “Dedicated to the One I Love.” Only in this case there is more than one love. First, I’d like to acknowledge a few good friends who have waited patiently for me to finish my thesis and without whose emotional support this work would have been difficult. They constantly rooted for me and kept me going. I am thankful to my family members, in particular to my brother, Butch, and his wonderful daughters, Brandy and Niki, for allowing me to be an absentee sister and aunt, yet they continued to offer words of encouragement throughout the years. In addition, I wish that my parents were here to see this moment because they always knew my persistence usually worked in my favor. They would have been proud to see their first family member receive a graduate degree. As a mother, you think of yourself as a role model for your children, but little did Seth, Michael, and Jaclyn know that they were my role models. Their faith in me inspired me to continue this thesis to completion. I raised them to never give up on something while they were in the middle of it and to finish what they started. Those words came back to me from my children more than I can count. My children were selfless on many, many occasions when I felt that I was needed, yet they imparted their own inner strengths and pushed me to continue my work, allowing me to keep my dream alive. I’d like to thank my dear daughter-in-law, Joyce, who was always there with her smiling face and constantly cheer me on. Now as new parents, Seth and Joyce have a son, Zachary, who I hope to inspire one day to become a steward of the environment. When I began my thesis, we had one fish (Fluffy), two birds (Mine and Yours), two cats (Percy and Cookie), and three dogs (Calvin, Lillie, and Lucy). As I finished my thesis, only one cat and three dogs remained. I want to acknowledge the pets that could not hang in for me to finish, but especially to our fluffy kitty, Percy, who died two months ago. He provided never-ending companionship while he sat on my lap as I did my research and wrote my thesis, keeping constant vigilance on my comings and goings. Next, to Calvin, Lillie, Lucy, and Cookie who followed me around every day as if we were in a parade. Even though I was quite boring, all of them were by my side, day in and day out, not asking for anything but an occasional pat or treat. They were the consummate friends. In spite of support from colleagues, friends, children, and pets, I would never have even started this thesis without the understanding and generosity from my loving husband, Allan. Besides being an established scientist, he was always inspirational, supportive, funny, an excellent cook, a fantastic editor and a true friend. Not only did he see the value of my work for my own personal growth, but he understands what this research means to the scientific community and to the people who will be affected by global sea level rise in the near future. I dedicate my thesis to Allan because he always believed in me and never let me down. ACKNOWLEDGMENTS This thesis could not have been completed without the help of numerous individuals who played crucial inspirational and supporting roles. My first inspiration came from Donna Williams during our years together as members of the League of Women Voters. Her passion and professionalism for protecting and enhancing the environment is a model which all of us should live by. Her husband, Ted Williams, an environmental writer who challenges all of us to think critically, was always on the other end of cyber space to offer words of encouragement and to provide an endless supply of jokes, when needed. When I went back to college in 2001, Dr. John Gerber was my sponsor, my professor, and an advocate for my education. He has continued his support by willingly accepting my request to become a member of my thesis committee. He has provided stability for me during my ups and downs at the University of Massachusetts. Dr. Robin Harrington was not only a member of my committee, but she became a friend and a mentor for me throughout my graduate school years. I will always be grateful to her for excellent lectures, her open door policy, and her warm hugs when either one of us needed one. She was truly an inspiration to me, particularly as a woman scientist. Last, but certainly not least, my thesis advisor, Dr. Jack Finn, took me on as his graduate student in 2005, without even a moment of hesitation on his part. Jack is a very humble person, but the wealth of knowledge he has about the oceans, coastal areas, ecology, spatial data modeling, and more specifically, mathematics, always astounded me. Between his knowledge, working style, views on life, sense of humor, and devotion to the vi sciences, I never wanted to finish. If it wasn’t for deadlines set by the University, I would still be working away. I am also indebted to several researchers and organizations for their investigative work and historical data collections. Data from “The Massachusetts Shoreline Change Projected,” led by Dr. Robert Thieler of the United States Geological Survey (USGS), was invaluable to me and established the underlying structure of my thesis. All this data was made readily available to me by the Massachusetts Office of Coastal Zone Management (MA CZM). The work of a USGS geologist, Robert N. Oldale, whose book I purchased in the mid-1990s (Cape Cod and the Islands, the Geologic Story) led me to become when of his favorite followers. The Office of Geographic and Environmental Information (MassGIS), the USGS, the National Oceanic and Atmospheric Administration (NOAA), the Permanent Service for Mean Sea Level (PSMSL) in the United Kingdom, the United States Department of Agriculture (USDA), and the Natural Resources Conservation Service (NRCS) all provided data relevant to my research. vii ABSTRACT ANALYSIS OF COASTAL EROSION ON MARTHA’S VINEYARD, MASSACHUSETTS: A PARAGLACIAL ISLAND SEPTEMBER 2008 DENISE BROUILLETTE-JACOBSON, B.A., UNIVERSITY OF MASSACHUSETTS AMHERST M.S., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor John T. Finn As the sea rises in response to global climate changes, small islands will lose a significant portion of their land through ensuing erosion processes. The particular vulnerability of small island systems led me to choose Martha’s Vineyard (MV), a 248 km2 paraglacial island, 8 km off the south shore of Cape Cod, Massachusetts, as a model system with which to analyze the interrelated problems of sea level rise (SLR) and coastal erosion. Historical data documented ongoing SLR (~3mm/yr) in the vicinity of MV. Three study sites differing in geomorphological and climatological properties, on the island’s south (SS), northwest (NW), and northeastern (NE) coasts, were selected for further study. Mathematical models and spatial data analysis, as well as data on shoreline erosion from almost 1500 transects, were employed to evaluate the roles of geology, surficial geology, wetlands, land use, soils, percent of sand, slope, erodible land, wind, waves, and compass direction in the erosion processes at each site. These analyses indicated that: 1) the three sites manifested different rates of erosion and accretion, from a loss of approximately 0.1 m/yr at the NE and NW sites to over 1.7 m/yr at the SS site; 2) the NE and NW sites fit the ratio predicted by Bruun for the rate of erosion vs. SLR, viii but the SS site exceeded that ratio more than fivefold; 3) the shoreline erosion patterns for all three sites are dominated by short-range effects, not long-range stable effects; 4) geological components play key roles in erosion on MV, a possibility consistent with the island’s paraglacial nature; and 5) the south side of MV is the segment of the coastline that is particularly vulnerable to significant erosion over the next 100 years. These conclusions were not evident from simple statistical analyses.