Stochastic Dynamics of Barrier Island Elevation
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Stability Domains in Barrier Island Dune Systems J
Ecological Complexity 2 (2005) 410–430 http://www.elsevier.com/locate/ecocom Stability domains in barrier island dune systems J. Anthony Stallins * Department of Geography, Florida State University, Room 323 Bellamy Bldg. Tallahassee, FL 32306, USA Received 1 February 2005; received in revised form 12 April 2005; accepted 25 April 2005 Available online 17 October 2005 Abstract Early ecological descriptions of barrier island dune landscapes recognized the importance of biogeomorphic feedbacks and thresholds. However, these dynamics have not been formally linked to complexity theory. In this article, I develop models of dune landscape phase states, or stability domains, based on a synthesis of these prior studies and statistical analyses. Data for these analyses were obtained from compositional and topographic sampling along Sapelo Island, Georgia and South Core Banks, North Carolina. These undeveloped barrier islands are at opposite ends of a regional meteorological gradient in storm- forced overwash disturbance along the southeastern US Atlantic coast. The topography and plant functional group abundances on each island were supportive of earlier studies noting the propensity for distinct self-organizing biogeomorphic feedbacks to emerge along barrier coasts. On South Core Banks, where storm forcings of overwash are more frequent, the recovery processes initiated by burial-tolerant species may reduce topographic resistance to overwash exposure and contagion. On Sapelo Island, a greater abundance of dune-building and burial-intolerant swale species may confer a higher topographic roughness and more resistance to overwash exposure and contagion. Conceptually, the biogeomorphic modifications of overwash forcings on each island perpetuate the habitat conditions and dominant dune plant species in a weak positive feedback. -
Natural and Anthropogenic Influences on the Morphodynamics of Sandy and Mixed Sand and Gravel Beaches Tiffany Roberts University of South Florida, [email protected]
University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School January 2012 Natural and Anthropogenic Influences on the Morphodynamics of Sandy and Mixed Sand and Gravel Beaches Tiffany Roberts University of South Florida, [email protected] Follow this and additional works at: http://scholarcommons.usf.edu/etd Part of the American Studies Commons, Geology Commons, and the Geomorphology Commons Scholar Commons Citation Roberts, Tiffany, "Natural and Anthropogenic Influences on the Morphodynamics of Sandy and Mixed Sand and Gravel Beaches" (2012). Graduate Theses and Dissertations. http://scholarcommons.usf.edu/etd/4216 This Dissertation is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Natural and Anthropogenic Influences on the Morphodynamics of Sandy and Mixed Sand and Gravel Beaches by Tiffany M. Roberts A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Geology College of Arts and Sciences University of South Florida Major Professor: Ping Wang, Ph.D. Bogdan P. Onac, Ph.D. Nathaniel Plant, Ph.D. Jack A. Puleo, Ph.D. Julie D. Rosati, Ph.D. Date of Approval: July 12, 2012 Keywords: barrier island beaches, beach morphodynamics, beach nourishment, longshore sediment transport, cross-shore sediment transport. Copyright © 2012, Tiffany M. Roberts Dedication To my eternally supportive mother, Darlene, my brother and sister, Trey and Amber, my aunt Pat, and the friends who have been by my side through every challenge and triumph. -
Barrier Island Migration Sea Level Rise and the Future
Barrier Island Migration stable location and absence of historic inlets in this area suggest that barrier migration may not be a These barrier islands retreated or migrated north- continuous process over timescales of a thousand ward as the ocean continued rising. There is some years or less. Further to the east, the barriers are debate about how the barriers actually moved. more mobile and one can find evidence of barrier Some research suggests that the barriers slowly island rollover processes such as old flood shoals drowned in place and then “jumped” or “skipped” in the bay that were associated with inlets that have landward to a new position coinciding with the new opened and closed naturally over the last several position of the shoreline. More recent studies indi- hundred years. cate the islands move in a more continuous process where sand is transported across the island from the ocean to the bay, allowing the island to migrate Sea Level Rise and the Future landward. There are three primary ways that sand can be transported across a barrier island: inlet Along the New York coast, sea level is not only ris- formation, overwash processes and eolian (or wind) ing, the land is also slowly sinking, or subsiding due transport. On Long Island’s south shore, the inlets to geologic processes. The rise in the water level in are actually far more important than either over- relation to the land surface due to the sinking of the washes or the wind in terms of moving sand land- land and the raising of the sea is known as relative ward and driving barrier migration. -
Historical Changes in the Mississippi-Alabama Barrier Islands and the Roles of Extreme Storms, Sea Level, and Human Activities
HISTORICAL CHANGES IN THE MISSISSIPPI-ALABAMA BARRIER ISLANDS AND THE ROLES OF EXTREME STORMS, SEA LEVEL, AND HUMAN ACTIVITIES Robert A. Morton 88∞46'0"W 88∞44'0"W 88∞42'0"W 88∞40'0"W 88∞38'0"W 88∞36'0"W 88∞34'0"W 88∞32'0"W 88∞30'0"W 88∞28'0"W 88∞26'0"W 88∞24'0"W 88∞22'0"W 88∞20'0"W 88∞18'0"W 30∞18'0"N 30∞18'0"N 30∞20'0"N Horn Island 30∞20'0"N Petit Bois Island 30∞16'0"N 30∞16'0"N 30∞18'0"N 30∞18'0"N 2005 2005 1996 Dauphin Island 1996 2005 1986 1986 30∞16'0"N Kilometers 30∞14'0"N 0 1 2 3 4 5 1966 30∞16'0"N 1950 30∞14'0"N 1950 Kilometers 1917 0 1 2 3 4 5 1917 1848 1849 30∞14'0"N 30∞14'0"N 30∞12'0"N 30∞12'0"N 30∞12'0"N 30∞12'0"N 30∞10'0"N 30∞10'0"N 88∞46'0"W 88∞44'0"W 88∞42'0"W 88∞40'0"W 88∞38'0"W 88∞36'0"W 88∞34'0"W 88∞32'0"W 88∞30'0"W 88∞28'0"W 88∞26'0"W 88∞24'0"W 88∞22'0"W 88∞20'0"W 88∞18'0"W 89∞10'0"W 89∞8'0"W 89∞6'0"W 89∞4'0"W 88∞58'0"W 88∞56'0"W 88∞54'0"W 88∞52'0"W 30∞16'0"N Cat Island Ship Island 30∞16'0"N 2005 30∞14'0"N 1996 30∞14'0"N 1986 Kilometers 1966 0 1 2 3 30∞14'0"N 1950 30∞14'0"N 1917 1848 Fort 2005 Massachusetts 1995 1986 Kilometers 1966 0 1 2 3 30∞12'0"N 1950 30∞12'0"N 1917 30∞12'0"N 30∞12'0"N 1848 89∞10'0"W 89∞8'0"W 89∞6'0"W 89∞4'0"W 88∞58'0"W 88∞56'0"W 88∞54'0"W 88∞52'0"W Open-File Report 2007-1161 U.S. -
Types and Causes of Beach Erosion Anomaly Areas in the U.S. East Coast Barrier Island System: Stabilized Tidal Inlets
Middle States Geographer, 2007, 40:158-170 TYPES AND CAUSES OF BEACH EROSION ANOMALY AREAS IN THE U.S. EAST COAST BARRIER ISLAND SYSTEM: STABILIZED TIDAL INLETS Francis A. Galgano Jr. Department of Geography and the Environment Villanova University 800 Lancaster Avenue Villanova, Pennsylvania 19085 ABSTRACT: Contemporary research suggests that most U.S. beaches are eroding, and this has become an important political and economic issue because beachfront development is increasingly at risk. In fact, the Heinz Center and Federal Emergency Management Agency (FEMA) estimate that over the next 60 years, beach erosion may claim one out of four homes within 150 meters of the U.S. shoreline. This is significant because approximately 350,000 structures are located with 150 meters of the shoreline in the lower 48 states, not including densely populated coastal cities such as New York and Miami. Along the East Coast, most beaches are eroding at 1 to 1.5 meters per year. However, beach erosion is especially problematic along so-called beach erosion anomaly areas (EAAs) where erosion rates can be as much as five times the rate along adjacent beaches. Identifying and understanding these places is important because property values along U.S. East Coast barrier islands are estimated to be in the trillions of dollars, and the resultant beach erosion may also destroy irreplaceable habitat. There are a number of factors⎯natural and anthropogenic⎯that cause beaches to erode at anomalous rates. This paper will focus on the barrier island system of the U.S. East Coast, classify beach EAAs, and examine beach erosion down drift from stabilized tidal inlets because they are perhaps the most spatially extensive and destructive EAAs. -
Understanding Our Coastal Environment
Preface The South Carolina Beachfront Management Act In the Beginning The Coastal Zone Management Act of 1977 was enacted to protect our coastal resources from unwise development. This legislation served the beaches well during its first decade, but as South Carolina became a more popular tourist destination, it became apparent that the portion of the Act that dealt with beaches was inadequate. As development crept seaward, seawalls and rock revetments proliferated, damaging the public’s beach. In many areas there was no beach left at high tide. In some areas, there was no beach at low tide, either. In 1988 and again in 1990, South Carolina’s legislators took action and amended and strengthened the Coastal Zone Management Act. The resulting Beachfront Management Act protects South Carolina’s sandy shores by increasing the state’s jurisdiction and encouraging development to move landward. South Carolina’s Beachfront Jurisdiction To find the boundaries of this jurisdiction, staff from the Office of Ocean and Coastal Resource Management must first locate the baseline, which is the crest of the primary oceanfront sand dune. Where there are no dunes, the agency uses scientific methods to determine where the natural dune would lie if natural or man-made occurrences had not interfered with nature’s dune building process. The setback line is the most landward boundary and is measured from the baseline. To find the depth of the setback line, the beach’s average annual erosion rate for the past forty years is calculated and multiplied by forty. For example, if the erosion rate is one foot per year, the results will be a setback line that stretches forty feet from the baseline. -
BARRIER ISLAND STATUS REPORT Fiscal Year 2020 Annual Plan
BARRIER ISLAND STATUS REPORT Fiscal Year 2020 Annual Plan In compliance with Act 297 of the 2006 Regular Legislative Session, the Coastal Protection and Restoration Authority (CPRA) provides this barrier island status report as part of the Annual Plan document, which will be submitted to each member of the Louisiana Legislature. The current Barrier Island Status report is available electronically at the CPRA website. Please visit www.coastal.LA.gov to download and review the full report. A summary of the report is provided below. CONSTRUCTED PROJECTS The coastlines of the modern Mississippi River delta plain are bordered by numerous barrier islands from Raccoon Island in the west to Hewes Point in the northern Chandeleur Islands (Figure 1). These barrier islands could be grouped to represent fragmented remnants of distal extremities of several major delta lobes and headlands: to identify these barrier islands with their respective delta lobes they have been grouped from west to east as the Early Lafourche Delta System, Late Lafourche Delta System, Modern Delta System, and the St. Bernard Delta System. The back- barrier lagoons are connected to the Gulf of Mexico by approximately 25 tidal inlets which separate these barrier islands from each other and allow the exchange of diurnal tides. Figure 1: Location of barrier islands belonging to Early Lafourche, Late Lafourche, Modern, and St. Bernard barrier island systems in Louisiana The restoration of Louisiana’s barrier islands and barrier island systems has been a priority for a number of restoration programs over the past several decades and over 40 barrier island projects have been constructed to date (including 13 in the Early Lafourche Delta System, 18 in the Late Lafourche Delta System, 9 in the Modern Delta System, and 2 in the St. -
The Modified Bruun Rule Extended for Landward Transport
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by UNL | Libraries University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln US Army Research U.S. Department of Defense 2013 The modified Bruun Rule extended for landward transport J.D. Rosati U. S. Army Corps of Engineers, [email protected] R.G. Dean University of Florida T.L. Walton Coastal Tech Corp Follow this and additional works at: https://digitalcommons.unl.edu/usarmyresearch Rosati, J.D.; Dean, R.G.; and Walton, T.L., "The modified Bruun Rule extended for landward transport" (2013). US Army Research. 219. https://digitalcommons.unl.edu/usarmyresearch/219 This Article is brought to you for free and open access by the U.S. Department of Defense at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in US Army Research by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Marine Geology 340 (2013) 71–81 Contents lists available at SciVerse ScienceDirect Marine Geology journal homepage: www.elsevier.com/locate/margeo The modified Bruun Rule extended for landward transport J.D. Rosati a,⁎, R.G. Dean b, T.L. Walton c a U. S. Army Corps of Engineers, Washington, DC 20314, United States b University of Florida, Gainesville, FL 32605, United States c Coastal Tech Corp., Tallahassee, FL, United States article info abstract Article history: The Bruun Rule (Bruun, 1954, 1962) provides a relationship between sea level rise and shoreline retreat, and Received 3 January 2013 has been widely applied by the engineering and scientific communities to interpret shoreline changes and to Received in revised form 24 April 2013 plan for possible future increases in sea level rise rates. -
Optimal Hurricane Overwash Thickness for Maximizing Marsh Resilience to Sea Level Rise
W&M ScholarWorks VIMS Articles Virginia Institute of Marine Science 2016 Optimal hurricane overwash thickness for maximizing marsh resilience to sea level rise David C. Walters Virginia Institute of Marine Science Matthew L. Kirwan Virginia Institute of Marine Science Follow this and additional works at: https://scholarworks.wm.edu/vimsarticles Part of the Marine Biology Commons Recommended Citation Walters, D. C. and Kirwan, M. L. (2016), Optimal hurricane overwash thickness for maximizing marsh resilience to sea level rise. Ecol Evol, 6: 2948–2956. doi:10.1002/ece3.2024 This Article is brought to you for free and open access by the Virginia Institute of Marine Science at W&M ScholarWorks. It has been accepted for inclusion in VIMS Articles by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. Optimal hurricane overwash thickness for maximizing marsh resilience to sea level rise David C. Walters & Matthew L. Kirwan Department of Physical Sciences, Virginia Institute of Marine Science, College of William and Mary, PO Box 1346, Gloucester Point, Virginia 23062 Keywords Abstract Climate change, coastal geomorphology, disturbance event, ecosystem resiliency, press The interplay between storms and sea level rise, and between ecology and sedi- and pulse stresses, salt marsh, storm ment transport governs the behavior of rapidly evolving coastal ecosystems such deposition. as marshes and barrier islands. Sediment deposition during hurricanes is thought to increase the resilience of salt marshes to sea level rise by increasing Correspondence soil elevation and vegetation productivity. We use mesocosms to simulate burial David C. Walters, Department of Physical of Spartina alterniflora during hurricane-induced overwash events of various Sciences, Virginia Institute of Marine Science, thickness (0–60 cm), and find that adventitious root growth within the over- College of William and Mary, PO Box 1386, Gloucester Point, VA 23062. -
Chapter One the North Carolina Coast
11 Chapter One The North Carolina Coast 12 THE ECOLOGY Visitors to the North Carolina coast might well think that barrier islands and their beaches are the heart of the coastal area. They are, after all, the center of activity for thousands of people every summer day. An aerial photograph of the coast tells a different story, though: the islands appear to be only a slender, slightly bowed, ribbon in the midst of an enormous sea. Water domi- nates the image, an image that is the key to understand- ing North Carolina’s coastal ecosystem. The Atlantic Ocean, too wide for all of it to fit into the frame of the photograph, has an equal amount of influence in shaping the lands, waters, plants and animals of the coastal area. Wind, waves, and tides – all affected by (and affecting) the huge body of water – are constantly at work, shaping the size and location of barrier islands and inlets, determining what types of plants will grow where. For example, just wind-borne salt significantly affects how maritime trees, and thus the shape of entire forests, develop. Climate, which the ocean affects through the temperature of water currents, in turn influences the types of plants and animals found along the coast. The rising and falling of tides affect not only the types of organisms found on a beach and the specific places where they can survive, but the types of species found behind the barrier islands, in the sounds, as well. 13 THE ECOLOGY This leads to the other half of that watery photograph - the estuarine system. -
Coastal Barriers - D
COASTAL ZONES AND ESTUARIES – Coastal Barriers - D. M. FitzGerald and I. V. Buynevich COASTAL BARRIERS D. M. FitzGerald and I. V. Buynevich Department of Earth Sciences, Boston University, USA Keywords: barrier, beach, spit, inlet, barrier stratigraphy, barrier evolution Contents 1. Introduction 2. Physical Description 2.1 Beach 2.2 Barrier Interior 2.3 Landward Margin 3. Global Distribution and Tectonic Setting 3.1 General 3.2 Tectonic Controls 3.3 Climatic Controls 4. Barrier Types 4.1 Barrier Spits 4.2 Spit Initiation 4.2.1 Recurved Spits 4.2.2 Cuspate Spits 4.2.3 Flying Spits 4.2.4 Tombolos 4.2.5 Cuspate Forelands 4.3 Welded Barriers 4.4 Barrier Islands 4.4.1 Origin of Barrier Islands 4.4.2 E. de Beaumont 4.4.3 G.K. Gilbert 4.4.4 W.D. McGee 4.4.5 D.W. Johnson 4.4.6 John Hoyt 4.4.7 John Fisher 4.4.8 Recent Barrier Studies 5. BarrierUNESCO Coast Morphology – EOLSS 5.1 Hydrographic Regime and Types of Barrier Coast 5.1.1 Wave-dominatedSAMPLE Coast CHAPTERS 5.1.2 Mixed-Energy Coast 5.1.3 Tide-Dominated Coasts 5.2 Georgia Bight – A Case Study 6. Prograding, Retrograding, and Aggrading Barriers 6.1 Prograding Barriers 6.2 Retrograding Barriers 6.3 Aggrading Barriers 7. Barrier Stratigraphy 7.1 Prograding barrier (regressive stratigraphy) ©Encyclopedia of Life Support Systems (EOLSS) COASTAL ZONES AND ESTUARIES – Coastal Barriers - D. M. FitzGerald and I. V. Buynevich 7.2 Retrograding barrier (transgressive stratigraphy) 7.3 Aggrading barrier stratigraphy Glossary Bibliography Biographical Sketches Summary Barriers occur on a worldwide basis but are predominantly found along Amero-trailing edge continental margins in coastal plain settings where the supply of sand is abundant. -
Barrier-Island Migration Dominates Ecogeomorphic Feedbacks And
Publisher: GSA Journal: GEOL: Geology DOI:10.1130/G38459.1 1 Barrier-island migration dominates ecogeomorphic 2 feedbacks and drives salt marsh loss along the Virginia 3 Atlantic Coast, USA 4 Charles D. Deaton1,*, Christopher J. Hein2, and Matthew L. Kirwan2 5 1Department of Geology, College of William and Mary, Williamsburg, Virginia 23185, 6 USA 7 2Department of Physical Sciences, Virginia Institute of Marine Science, College of 8 William and Mary, Gloucester Point, Virginia 23062, USA 9 *Current address: Institute of Marine Sciences, University of North Carolina at Chapel 10 Hill, Morehead City, North Carolina 28557, USA; E-mail: [email protected]. 11 ABSTRACT 12 Coupling between barrier islands and their associated backbarrier environments 13 (salt marsh, tidal flats) leads to complex ecogeomorphic feedbacks that are proposed to 14 control the response of barrier island systems to relative sea-level rise. This study tests 15 the applicability of these still theoretical concepts through investigation of the Virginia 16 barrier islands, which are located in a hotspot of accelerated sea-level rise. Using 17 historical maps and photographs from 1851 to 2010, we determine that rapid landward 18 island migration (1–6 m yr-1) is leading to backbarrier area reduction and large-scale salt 19 marsh loss (63 km2 or 19%) at a rate of 0.45 km2 yr-1. Landward barrier-island migration 20 far outpaces upland marsh migration and was responsible for 51% of marsh loss, with the 21 remainder due to backbarrier processes (e.g., edge erosion). In direct contrast to proposed 22 ecogeomorphic feedbacks linking barrier island and backbarrier environments, shoreline Page 1 of 19 Publisher: GSA Journal: GEOL: Geology DOI:10.1130/G38459.1 23 retreat rates were not related to changes in backbarrier marsh, open-water areas, or tidal 24 prism.