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Evolution of 3-D geologic framework modeling and its application to groundwater flow studies

In this Fact Sheet, the authors discuss the evolution of project 3-D subsurface framework modeling, research in hydrostratigraphy and airborne geophysics, and methodologies used to link geologic and groundwater flow models.
Authors
Charles D. Blome, David V. Smith

Atlas of relations between climatic parameters and distributions of important trees and shrubs in North America—Modern data for climatic estimation from vegetation inventories

Vegetation inventories (plant taxa present in a vegetation assemblage at a given site) can be used to estimate climatic parameters based on the identification of the range of a given parameter where all taxa in an assemblage overlap ("Mutual Climatic Range"). For the reconstruction of past climates from fossil or subfossil plant assemblages, we assembled the data necessary for such analyses for 53
Authors
Robert S. Thompson, Katherine H. Anderson, Richard T. Pelltier, Laura E. Strickland, Sarah L. Shafer, Patrick J. Bartlein

Soil genesis on the island of Bermuda in the Quaternary: the importance of African dust transport and deposition

The origin of terra rossa, red or reddish-brown, clay-rich soils overlying high-purity carbonate substrates, has intrigued geologists and pedologists for decades. Terra rossa soils can form from accumulation of insoluble residues during dissolution of the host limestones, addition of volcanic ash, or addition of externally derived, long-range-transported (LRT) aeolian particles. We studied soils a
Authors
Daniel R. Muhs, James R. Budahn, Joseph M. Prospero, Gary Skipp, Stanley R. Herwitz

The Adaptation for Conservation Targets (ACT) Framework: A tool for incorporating climate change into natural resource management

As natural resource management agencies and conservation organizations seek guidance on responding to climate change, myriad potential actions and strategies have been proposed for increasing the long-term viability of some attributes of natural systems. Managers need practical tools for selecting among these actions and strategies to develop a tailored management approach for specific targets at
Authors
Molly S. Cross, Erika S. Zavaleta, Dominique Bachelet, Marjorie L. Brooks, Carolyn A.F. Enquist, Erica Fleishman, Lisa J. Graumlich, Craig R. Groves, Lee Hannah, Lara J. Hansen, Gregory D. Hayward, Marni Koopman, Joshua J. Lawler, Jay Malcolm, John R. Nordgren, Brian Petersen, Erika Rowland, Daniel Scott, Sarah L. Shafer, M. Rebecca Shaw, Gary Tabor

Combining satellite-based fire observations and ground-based lightning detections to identify lightning fires across the conterminous USA

Lightning fires are a common natural disturbance in North America, and account for the largest proportion of the area burned by wildfires each year. Yet, the spatiotemporal patterns of lightning fires in the conterminous US are not well understood due to limitations of existing fire databases. Our goal here was to develop and test an algorithm that combined MODIS fire detections with lightning det
Authors
A. Bar-Massada, T. J. Hawbaker, S. I. Stewart, V. C. Radeloff

Mapping outdoor recreationists' perceived social values for ecosystem services at Hinchinbrook Island National Park, Australia

Coastal ecosystems are increasingly faced with human impacts. To better understand these changing conditions, biophysical and economic values of nature have been used to prioritize spatial planning efforts and ecosystem-based management of human activities. Less is known, however, about how to characterize and represent non-material values in decision-making. We collected on-site and mailback surv
Authors
Carena J. van Riper, Gerard T. Kyle, Stephen G. Sutton, Melinda Barnes, Benson C. Sherrouse

Holocene alluvial stratigraphy and response to climate change in the Roaring River valley, Front Range, Colorado, USA

Stratigraphic analyses and radiocarbon geochronology of alluvial deposits exposed along the Roaring River, Colorado, lead to three principal conclusions: (1) the opinion that stream channels in the higher parts of the Front Range are relics of the Pleistocene and nonalluvial under the present climate, as argued in a water-rights trial USA v. Colorado, is untenable, (2) beds of clast-supported grav
Authors
Richard F. Madole

Quantitative estimation of climatic parameters from vegetation data in North America by the mutual climatic range technique

The mutual climatic range (MCR) technique is perhaps the most widely used method for estimating past climatic parameters from fossil assemblages, largely because it can be conducted on a simple list of the taxa present in an assemblage. When applied to plant macrofossil data, this unweighted approach (MCRun) will frequently identify a large range for a given climatic parameter where the species in
Authors
Katherine H. Anderson, Patrick J. Bartlein, Laura E. Strickland, Richard T. Pelltier, Robert S. Thompson, Sarah L. Shafer

Sea-level history of past interglacial periods: New evidence from uranium-series dating of corals from Curaçao, Leeward Antilles islands

Curaçao has reef terraces with the potential to provide sea-level histories of interglacial periods. Ages of the Hato (upper) unit of the “Lower Terrace” indicate that this reef dates to the last interglacial period, Marine Isotope Stage (MIS) 5.5. On Curaçao, this high sea stand lasted at least 8000 yr (~ 126 to ~ 118 ka). Elevations and age of this reef show that late Quaternary uplift rates on
Authors
Daniel R. Muhs, John M. Pandolfi, Kathleen R. Simmons, R. Randall Schumann

Modelling ecosystem service flows under uncertainty with stochiastic SPAN

Ecosystem service models are increasingly in demand for decision making. However, the data required to run these models are often patchy, missing, outdated, or untrustworthy. Further, communication of data and model uncertainty to decision makers is often either absent or unintuitive. In this work, we introduce a systematic approach to addressing both the data gap and the difficulty in communicatin
Authors
Gary W. Johnson, Robert R. Snapp, Ferdinando Villa, Kenneth J. Bagstad

Paleontology and geochronology of the Long Beach core sites and monitoring wells, Long Beach, California

The U.S. Geological Survey's Focus on Quaternary Stratigraphy in Los Angeles (FOQUS-LA) project was a cooperative coring program between Federal, State, and local agencies. It was designed to provide a better understanding of earthquake potentials and to develop a stratigraphic model of the western Los Angeles Basin in California. The biostratigraphic, geochronologic, and paleoecologic analyses of
Authors
Kristin McDougall, John Hillhouse, Charles Powell, Shannon Mahan, Elmira Wan, Andrei M. Sarna-Wojcicki

Rocky Mountain hydroclimate: Holocene variability and the role of insolation, ENSO, and the North American Monsoon

Over the period of instrumental records, precipitation maximum in the headwaters of the Colorado Rocky Mountains has been dominated by winter snow, with a substantial degree of interannual variability linked to Pacific ocean–atmosphere dynamics. High-elevation snowpack is an important water storage that is carefully observed in order to meet increasing water demands in the greater semi-arid region
Authors
Lesleigh Anderson