Publications
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A review of abrupt permafrost thaw: Definitions, usage, and a proposed conceptual framework A review of abrupt permafrost thaw: Definitions, usage, and a proposed conceptual framework
Purpose of Review We review how ‘abrupt thaw’ has been used in published studies, compare these definitions to abrupt processes in other Earth science disciplines, and provide a definitive framework for how abrupt thaw should be used in the context of permafrost science.Recent Findings We address several aspects of permafrost systems necessary for abrupt thaw to occur and propose a...
Authors
Hailey Webb, Matthias Fuchs, Benjamin W. Abbott, Thomas A. Douglas, Clayton D. Elder, Jessica G. Ernakovich, Eugenie Euskirchen, Mathias Göckede, Guido Grosse, Gustaf Hugelius, Miriam C. Jones, Charles Koven, Heather Kropp, Emma Lathrop, Wenwen Li, Michael M. Loranty, Susan M Natali, David Olefeldt, Christina Schädel, Edward A.G. Schuur, Oliver Sonnentag, Jens Strauss, Anna-Maria Virkkala, Merritt R. Turetsky
Cryptic ice wedge networks in Holocene peat, Yukon-Kuskokwim Delta, Alaska Cryptic ice wedge networks in Holocene peat, Yukon-Kuskokwim Delta, Alaska
The Yukon-Kuskokwim Delta (YKD), covering ~75,000 km2 of Alaska's discontinuous permafrost zone, has a historic (1902–2023) mean annual air temperature of ~−1°C and was previously thought to lack ice wedge networks. However, our recent investigations near Bethel, Alaska, revealed numerous near-surface ice wedges. Using 20 cm resolution aerial orthoimagery from 2018, we identified ~50...
Authors
Benjamin M. Jones, Mikhail Z. Kanevskiy, Melissa K. Ward Jones, Phillip R. Wilson, Isaiah Ditmer, Benjamin V. Gaglioti, Eric S. Klein, Rodrigo C. Rangel, Kristi L. Wallace, Miriam C. Jones, Matthew J. Wooller, Yuri Shur
Over, under, and through: Hydrologic connectivity and the future of coastal landscape salinization Over, under, and through: Hydrologic connectivity and the future of coastal landscape salinization
Seawater intrusion (SWI) affects coastal landscapes worldwide. Here we describe the hydrologic pathways through which SWI occurs - over land via storm surge or tidal flooding, under land via groundwater transport, and through watersheds via natural and artificial surface water channels—and how human modifications to those pathways alter patterns of SWI. We present an approach to advance
Authors
Ashley Helton, James Dennedy-Frank, Ryan Emanuel, Scott C Neubauer, Kyra Adams, Marcelo Ardon, Lawrence Band, Kevin A. Befus, Hanne Borstlap, Jamie Duberstein, Adam Gold, Kominoski John, Alex Manda, Holly A. Michael, Stephen Moysey, Allison Myers-Pigg, Justine Annaliese Neville, Gregory E. Noe, Jeeban Panthi, Elnaz Pezeshki, Matthew Sirianni, Ward.Nicolas
Geochemistry and spatial distribution of Neoproterozoic dike swarms from the northwestern tip of the Arabian-Nubian Shield: Implications for crustal extension Geochemistry and spatial distribution of Neoproterozoic dike swarms from the northwestern tip of the Arabian-Nubian Shield: Implications for crustal extension
Ediacaran dike swarms in the Arabian-Nubian Shield (ANS) provide key insights into post-collisional tectonics and magmatism. This study presents new chemical data, two 40Ar/39Ar ages, and spatial distribution analysis for dike swarms in the northernmost ANS exposures in SW Jordan. Hornblende from a lamprophyre sill intruding the Saramuj Conglomerate yielded a plateau age of ∼592 ± 3 Ma
Authors
Hind Ghanem, Abeer Salman, Ryan J. McAleer, Cees W. Passchier, Ghaleb H. Jarrar
Discovery of an intact Quaternary paleosol, Georgia Bight, USA Discovery of an intact Quaternary paleosol, Georgia Bight, USA
A previously buried paleosol was found on the continental shelf during a study of sea floor scour, nucleated by large artificial reef structures such as vessel hulks, barges, train cars, military vehicles, etc., called “scour nuclei”. It is a relic paleo-land surface of sapling-sized tree stumps, root systems, and fossil animal bone exhumed by scour processes active adjacent to the...
Authors
Ervan G. Garrison, Matthew Newton, Benjamin Prueitt, Emily C. Jones, Debra A. Willard
The stratigraphic record of the mid-Piacenzian warm period on the Atlantic Coastal Plain The stratigraphic record of the mid-Piacenzian warm period on the Atlantic Coastal Plain
Anthropogenic climate change is an existential threat to our planet, impacting everything from the delicate balance of ecosystems to the availability of vital resources. Coastal regions, particularly vulnerable to the impacts of climate change due to rising sea levels and changing weather patterns, are experiencing increased erosion, flooding, and habitat loss. Understanding how coastal...
Authors
Harry J. Dowsett, Whittney Spivey
The nonpoint source challenge: Obstacles and opportunities for meeting nutrient reduction goals in the Chesapeake Bay watershed The nonpoint source challenge: Obstacles and opportunities for meeting nutrient reduction goals in the Chesapeake Bay watershed
This document examines the Chesapeake Bay watershed response to nutrient and sediment reduction efforts under the Clean Water Act's total maximum daily load (TMDL) regulation. As the 2025 Chesapeake Bay TMDL deadline approaches, water quality goals remain unmet, primarily because of nonpoint source pollution, the largest remaining source of nutrients and sediment, and the primary...
Authors
Zachary M. Easton, Kurt Stephenson, Brian Benhem, J.K. Bohlke, Anthony R Buda, Amy S. Collick, Lara Fowler, Ellen Gilinsky, Andrew Miller, Gregory E. Noe, Leah Palm-Forster, Leonard Shabman, Tess Wynn-Thompson
Ice-lobe retreat, glacial lake levels and the North American varve chronology in the Deerfield basin of western Massachusetts Ice-lobe retreat, glacial lake levels and the North American varve chronology in the Deerfield basin of western Massachusetts
No abstract available.
Authors
Janet R. Stone, Mary L. DiGiacomo-Cohen, Steven B. Mabee, Julie Brigham-Grette, Byron D. Stone, Brandon L. Graham, Brian Yellen
Pysochron: A Python-based solution for calculating cosmogenic 26Al/10Be isochron burial ages Pysochron: A Python-based solution for calculating cosmogenic 26Al/10Be isochron burial ages
Cosmogenic 26Al/10Be isochron burial dating is a powerful tool for dating sediment burial over the past several million years. By measuring in-situ 26Al and 10Be in a suite of samples from the same depth in a buried deposit, it is possible to quantify the inventory of cosmogenic nuclides produced after burial, date the burial of shallow sediments, identify sediment reworking, and...
Authors
William Elijah Odom
Shifting baselines of coral-reef species composition from the Late Pleistocene to the present in the Florida Keys Shifting baselines of coral-reef species composition from the Late Pleistocene to the present in the Florida Keys
The ongoing global-scale reassembly of modern coral reefs is unprecedented compared with the observed stability of most late Quaternary reef assemblages. One notable exception is the marine isotope stage (MIS) 5e (ca 130–116 thousand years ago [ka]) reefs in the Florida Keys, where the ubiquitous shallow-water coral, Acropora palmata, was near absent. Little is known, however, about...
Authors
Lauren T. Toth, Anastasios Stathakopoulos, Scarlette Shan-Hwei Hsia, David A. Weinstein
Ecological thresholds and transformations due to climate change: The role of abiotic stress Ecological thresholds and transformations due to climate change: The role of abiotic stress
An ecological threshold is the point at which a comparatively small environmental change triggers an abrupt and disproportionately large ecological response. In the face of accelerating climate change, there is concern that abrupt ecosystem transformations will become more widespread as critical ecological thresholds are crossed. There has been ongoing debate, however, regarding the...
Authors
Michael Osland, John B. Bradford, Lauren T. Toth, Matthew J. Germino, James Grace, Judith Z. Drexler, Camille L. Stagg, Eric E. Grossman, Karen M. Thorne, Stephanie Romanach, Davina Passeri, Gregory E. Noe, Jessica R. Lacy, Ken Krauss, Kurt P. Kowalski, Glenn R. Guntenspergen, Neil K. Ganju, Nicholas Enwright, Joel A. Carr, Kristin B. Byrd, Kevin J. Buffington
By
Ecosystems Mission Area, Coastal and Marine Hazards and Resources Program, California Water Science Center, Eastern Ecological Science Center, Florence Bascom Geoscience Center, Forest and Rangeland Ecosystem Science Center, Pacific Coastal and Marine Science Center, Southwest Biological Science Center, St. Petersburg Coastal and Marine Science Center, Western Ecological Research Center (WERC), Western Geographic Science Center, Wetland and Aquatic Research Center , Woods Hole Coastal and Marine Science Center
Geochemical and tectonic evolution of the Ordovician Bronson Hill arc and Silurian and Devonian Connecticut Valley–Gaspé trough: Eastern Vermont and western New Hampshire, USA Geochemical and tectonic evolution of the Ordovician Bronson Hill arc and Silurian and Devonian Connecticut Valley–Gaspé trough: Eastern Vermont and western New Hampshire, USA
We present major and trace element whole-rock geochemistry of 94 samples from the Bronson Hill arc (BHA) and Connecticut Valley–Gaspé trough (CVGT). These data, when combined with recent zircon U-Pb geochronology and a reexamination of existing whole-rock geochemistry, enable a new analysis of the tectonic history of the ancient Laurentian-Ganderian margin in the northern Appalachians of...
Authors
Peter M. Valley, Gregory J. Walsh, Arthur J. Merschat, Ryan J. McAleer