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MIS 5e sea-level history along the Pacific coast of North America

The primary last interglacial, marine isotope substage (MIS) 5e records on the Pacific coast of North America, from Washington (USA) to Baja California Sur (Mexico), are found in the deposits of erosional marine terraces. Warmer coasts along the southern Golfo de California host both erosional marine terraces and constructional coral reef terraces. Because the northern part of the region is tecton
Authors
Daniel R. Muhs

Reply to “Evidence for humans at White Sands National Park during the Last Glacial Maximum could actually be for Clovis people ~13,000 years ago” by C. Vance Haynes, Jr.

Bennett et al. (2021, Science 373, 1528–1531) reported that ancient human footprints discovered in White Sands National Park, New Mexico date to between ∼23,000 and 21,000 years ago. Haynes (2022, PaleoAmerica, this issue) proposes two alternate hypotheses to explain the antiquity of the footprints. One is that they were made by humans crossing over older sediments sometime during the Holocene. Th
Authors
Jeffrey S. Pigati, Kathleen B. Springer, Vance T. Holliday, Matthew R. Bennett, David Bustos, Thomas M. Urban, Sally C. Reynolds, Daniel Odess

Urban landcover differentially drives day and nighttime air temperature across a semi-arid city

Semi-arid urban environments are undergoing an increase in both average air temperatures and in the frequency and intensity of extreme heat events. Within cities, different composition and densities of urban landcovers (ULC) influence local air temperatures, either mitigating or increasing heat. Currently, understanding how combinations of ULC influence air temperature at the block to neighborhood
Authors
Peter Christian Ibsen, G. Darrel Jenerette, Tyler Dell, Kenneth J. Bagstad, James E. Diffendorfer

Large fires or small fires, will they differ in affecting shifts in species composition and distributions under climate change?

Climate change is expected to increase fire activity, which has the potential to accelerate climate-induced shifts in species composition and distribution in the boreal-temperate ecotone. Wildfire can kill resident trees, and thus provide establishment opportunities for migrating tree species. However, the role of fire size and its interactions with tree species with varied life-history attributes
Authors
Wenru Xu, Hong S. He, Chao Huang, Shengwu Duan, Todd Hawbaker, Paul D. Henne, Yu Liang, Zhiliang Zhu

Surface ocean warming and acidification driven by rapid carbon release precedes Paleocene-Eocene Thermal Maximum

The Paleocene-Eocene Thermal Maximum (PETM) is recognized by a major negative carbon isotope (δ13C) excursion (CIE) signifying an injection of isotopically light carbon into exogenic reservoirs, the mass, source, and tempo of which continue to be debated. Evidence of a transient precursor carbon release(s) has been identified in a few localities, although it remains equivocal whether there is a gl
Authors
Tali L. Babila, Don E Penman, CD Standish, Monica Doubrawa, Tim J Bralower, Marci M. Robinson, Jean Self-Trail, Robert P. Speijer, Peter Stassen, Gavin L Foster, James C. Zachos

Mechanisms for retention of low molecular weight organic carbon varies with soil depth at a coastal prairie ecosystem

Though primary sources of carbon (C) to soil are plant inputs (e.g., rhizodeposits), the role of microorganisms as mediators of soil organic carbon (SOC) retention is increasingly recognized. Yet, insufficient knowledge of sub-soil processes complicates attempts to describe microbial-driven C cycling at depth as most studies of microbial-mineral-C interactions focus on surface horizons. We leverag
Authors
Jack McFarland, Corey Lawrence, Courtney Creamer, Marjorie S. Schulz, Christopher H. Conaway, Sara Peek, Mark Waldrop, Sabrina N. Sevilgen, Monica Haw

Assessing the accuracy and potential for improvement of the national land cover database’s tree canopy cover dataset in urban areas of the conterminous United States

The National Land Cover Database (NLCD) provides time-series data characterizing the land surface for the United States, including land cover and tree canopy cover (NLCD-TC). NLCD-TC was first published for 2001, followed by versions for 2011 (released in 2016) and 2011 and 2016 (released in 2019). As the only nationwide tree canopy layer, there is value in assessing NLCD-TC accuracy, given the ne
Authors
Mehdi Heris, Kenneth J. Bagstad, Austin Troy, Jarlath O’Neil-Dunne

Luminescence ages and new interpretations of the timing and deposition of Quaternary sediments at Natural Trap Cave, Wyoming

Natural Trap Cave, located in the Big Horn Mountains of north-central Wyoming, has a history of trapping and preserving a range of North American fauna that plummeted into the deep vertical entrance. These animal remains were buried and preserved within sediments of the main chamber and, in turn, have helped elucidate the procession of faunal dynamics during the latest glacial cycle. The cave loca
Authors
Shannon A. Mahan, John R. Wood, Dave M Lovelace, Juan Laden, Jenny McGuire, Julie Meachen

State of stress in areas of active unconventional oil and gas development in North America

In this paper, we present comprehensive data on stress orientation and relative magnitude in areas throughout North America where unconventional oil and gas are currently being developed. We find excellent agreement between maximum horizontal principal stress (SHmax) orientations over a wide range of depths, using multiple methods. In all basins studied, we observed coherent stress fields that in

Authors
Jens-Erik Lundstern, Mark D. Zoback

Multi-species, multi-country analysis reveals North Americans are willing to pay for transborder migratory species conservation

Migratory species often provide ecosystem service benefits to people in one country while receiving habitat support in other countries. The multinational cooperation that could help ensure continued provisioning of these benefits by migration may be informed by understanding the economic values people in different countries place on the benefits they derive from migratory wildlife.We conducted con
Authors
Wayne E. Thogmartin, Michelle A. Haefele, James E. Diffendorfer, Darius J. Semmens, Jonathan J. Derbridge, Aaron M. Lien, Ta-Ken Huang, Laura López-Hoffman

The global environmental agenda urgently needs a semantic web of knowledge

Progress in key social-ecological challenges of the global environmental agenda (e.g., climate change, biodiversity conservation, Sustainable Development Goals) is hampered by a lack of integration and synthesis of existing scientific evidence. Facing a fast-increasing volume of data, information remains compartmentalized to pre-defined scales and fields, rarely building its way up to collective k
Authors
Stefano Balbi, Kenneth J. Bagstad, Ainhoa Magrach, Maria Jose Sanz, Naikoa Aguilar-Amuchastegui, Carlo Guipponi, Ferdinando Villa