Skip to main content
U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Results

183859 results.

Alternate formats: RIS file of the first 3000 search results  |  Download all results as CSV | TSV | Excel  |  RSS feed based on this search  |  JSON version of this page of results

Page 473, results 11801 - 11825

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
USGS 2020 critical minerals review
Steven M. Fortier, Nedal T. Nassar, Karen D. Kelley, Graham W. Lederer, Jeffrey L. Mauk, Jane M. Hammarstrom, Warren C. Day, Robert R. Seal, II
2021, Mining Engineering (73) 32
Concerns about the lack of domestic production and availability of essential mineral raw materials were a recurring theme throughout the 20th century, particularly in the periods around armed conflicts (Congressional Research Service, 2019). These concerns resulted in the designation of particular minerals as “strategic” or “critical,” terms that commonly depend...
The concept of evanescent microbial ecosystems in Earth's atmosphere
Dale W. Griffin
2021, Book chapter, Microbes: The foundation stone of the biosphere
This essay presents the hypothesis that short-lived or evanescent microbial ecosystems exist in Earth’s lower troposphere (~ < 4 km). This hypothesis is supported by culture- and molecular-based studies that have shown diverse, viable, and metabolically active microbial communities within Earth’s atmospheric boundary layer. Surprisingly, microorganisms are routinely recovered in samples collected at...
Conservation status of the world’s skinks (Scincidae): Taxonomic and geographic patterns in extinction risk
David G. Chapple, Uri Roll, Monika Böhm, Rocio Aguilar, Andrew P. Amey, Chris C. Austin, Maureen Baling, Anthony J. Barley, Michael F. Bates, Aaron M. Bauer, Daniel G. Blackburn, Phil Bowles, Rafe M. Brown, S. R. Chandramouli, Laurent Chirio, Hal Cogger, Guarino R. Colli, Werner Conradie, Patrick J. Couper, Mark A. Cowan, Michael D. Craig, Indraneil Das, Aniruddha Datta-Roy, Chris R. Dickman, Ryan J. Ellis, Aaron L. Fenner, Stewart Ford, S. R. Ganesh, Michael G. Gardner, Peter Geissler, Graeme R. Gillespie, Frank Glaw, Matthew J. Greenlees, Oliver W. Griffith, L. Lee Grismer, Margaret L. Haines, D. James Harris, S. Blair Hedges, Rod A. Hitchmough, Conrad J. Hoskin, Mark N. Hutchinson, Ivan Ineich, Jordi Janssen, Gregory R. Johnston, Benjamin R. Karin, J. Scott Keogh, Frederick Kraus, Matthew LeBreton, Petros Lymberakis, Rafaqat Masroor, Peter J. McDonald, Sven Mecke, Jane Melville, Sabine Melzer, Damian R. Michael, Aurelien Miralles, Nicola J. Mitchell, Nicola J. Nelson, Truong Q. Nguyen, Cristiano de Campos Nogueira, Hidetoshi Ota, Panayiotis Pafilis, Olivier S. G. Pauwels, Ana Perera, Daniel Pincheira-Donoso, Robert Reed, Marco A. Ribeiro-Junior, Julia L. Riley, Sara Rocha, Pamela L. Rutherford, Ross A. Sadlier, Boaz Shacham, Glenn M. Shea, Richard Shine, Alex Slavenko, Adam Stow, Joanna Sumner, Oliver J. S. Tallowin, Roy Teale, Omar Torres-Carvajal, Jean-Francois Trape, Peter Uetz, Kanishka D. B. Ukuwela, Leonie E. Valentine, James U. Van Dyke, Dylan van Winkel, Raquel Vasconcelos, Miguel Vences, Philipp Wagner, Erik Wapstra, Geoffrey M. While, Martin J. Whiting, Camilla M. Whittington, Steve Wilson, Thomas Ziegler, Reid Tingley, Shai Meiri
2021, Biological Conservation (257)
Our knowledge of the conservation status of reptiles, the most diverse group of terrestrial vertebrates, has improved dramatically over the past decade, but still lags behind that of the other tetrapod groups. Here, we conduct the first comprehensive assessment (~92% of the world’s ~1,714 described species) of the conservation status...
Nocturnal incubation recess and flushing behavior by duck hens
Rebecca Croston, Sarah H. Peterson, C. Alex Hartman, Mark P. Herzog, Cliff L. Feldheim, Michael L. Casazza, Josh T. Ackerman
2021, Ecology and Evolution (11) 7292-7301
Incubating birds must balance the needs of their developing embryos with their own physiological needs, and many birds accomplish this by taking periodic breaks from incubation. Mallard (Anas platyrhynchos) and gadwall (Mareca strepera) hens typically take incubation recesses in the early morning and late afternoon, but recesses can also take...
Habitat heterogeneity, temperature, and primary productivity drive elevational gradients in avian species diversity
Kristen G. Dillon, Courtney J. Conway
2021, Ecology and Evolution (11) 5985-5997
AimAnticipating and mitigating the impacts of climate change on species diversity in montane ecosystems requires a mechanistic understanding of drivers of current patterns of diversity. We documented the shape of elevational gradients in avian species richness in North America and tested a suite of a priori predictions...
Wetlands in intermittently closed estuaries can build elevations to keep pace with sea-level rise
Karen M. Thorne, Kevin Buffington, Scott Jones, John L. Largier
2021, Estuarine, Coastal and Shelf Science (257)
Sea-level rise is a threat to coastal ecosystems, which have important conservation and economic value. While marsh response to sea-level rise has been well characterized for perennially open estuaries, bar-built intermittently-closed estuaries and their sea-level rise response are seldom addressed in the literature – despite being common globally. We seek to advance the conceptual...
Differential reliance on aquatic prey subsidies influences mercury exposure in riparian arachnids and songbirds
Allyson K. Jackson, Collin A. Eagles-Smith, W Douglas Robinson
2021, Ecology and Evolution (11) 7003-7017
Cross-ecosystem subsidies move substantial amounts of nutrients between ecosystems. Emergent aquatic insects are a particularly important prey source for riparian songbirds but may also move aquatic contaminants, such as mercury (Hg), to riparian food webs. While many studies focus on species that eat primarily emergent aquatic insects, we instead study...
Mars science helicopter: Compelling science enabled by an aerial platform
Jonathan Bapst, Timothy J Parker, J Balaram, T Tzanetos, L. H. Matthies, C D Edwards, Aaron Freeman, S Withrow-Maser, W. Carter Johnson, E Amador-French, Janice L. Bishop, Ingrid J. Daubar, Colin M. Dundas, Abigail A. Fraeman, Christopher W. Hamilton, C. Hardgrove, Briony H. N. Horgan, C. W. Leung, Y. Lin, A Mittelholz, B. P. Weiss
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
This whitepaper describes two conceptual vehicle designs, including possible tradeoffs within those designs, which would enable a wide array of innovative science investigations. In addition to describing vehicle capabilities, flight characteristics, and the breadth of enabled science for the two helicopter designs, we also introduce three mission concepts that showcase...
Aeolian processes and landforms across the Solar System: Science and technology requirements for the next decade
Timothy N. Titus, S. Diniega, L.K. Fenton, Lynn Neakrase, J. Nienhuis, J Radebaugh, Kaj E. Williams, James R. Zimbelman
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
Discussions of planetary atmospheric-surface interactions (including aeolian processes and phenomena and the resulting landforms) are often tied to a specific planetary body. Considering this, a series of workshops were initiated in 2008 to facilitate an interdisciplinary and interplanetary body approach to further our understanding of aeolian processes, phenomena, and landforms...
Science and technology requirements to explore caves in our Solar System
Timothy N. Titus, Janna Wynne, P. J. Boston, P. de Leon, C. Demirel-Floyd, H Jones, Francesco Sauro, Kyle Uckert, Ali-akbar Agha-Mohammadi, E. Calvin Alexander Jr., James W. Ashley, Armando Azua-Bustos, Leroy Chiao, Glen E. Cushing, J DeDecker, Alberto G. Fairen, A Frumkin, Jo de Waele, Gary L. Harris, Laura A. Kerber, Richard J. Leveille, Michael J. Malaska, Kavya Manyapu, Matteo Massironi, Ana Z. Miller, John E. Mylroie, Bogdan P. Onac, Scott Parazynski, Charity Phillips-Lander, Thomas Prettyman, Haley Sapers, Norbert Schorghofer, Dirk Schulze-Makuch, Red Whittaker, Kaj E. Williams, Uland Wong
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
We are in the incipient phase of exploring the subterranean realm of our Solar System. Planetary caves research offers interdisciplinary, cross-planetary body investigations spanning geology, climatology, astrobiology, robotics, and human use. Caves are of great importance in advancing our understanding of planetary processes and the search for life beyond Earth....
Planetary defense preparedness: Identifying the potential for post-asteroid impact time delayed and geographically displaced hazards
Timothy N. Titus, D. G. Robertson, Joel B. Sankey
Adam Oliphant, Itiya P. Aneece, editor(s)
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
A considerable amount of effort has been done to quantify impact effects from the impact of an asteroid. The effects usually considered are: blast, overpressure shock, thermal radiation, cratering, seismic shaking, ejecta, and tsunami (e.g. Hills & Goda, 1993; Collins et al., 2005, Rumpf et al., 2017). These first-order...
Solar-system-wide significance of Mars polar science
I. B. Smith, Wendy M. Calvin, D. E. Smith, C. Hansen, S. Diniega, A.S. McEwen, N. Thomas, D. Banfield, Timothy N. Titus, P. Becerra, M. Kahre, F. Forget, M. Hecht, S. Byrne, C. S. Hvidberg, P. O. Hayne, J. W. Head III, M. Mellon, B. Horgan, J. Mustard, J. Holt, A. Howard, D. McCleese, C. Stoker, P. James, N. E. Putzig, J. Whitten, P. Buhler, A. Spiga, M. Crismani, K. M. Aye, A. Portyankina, R. Orosei, A. Bramson, J. Hanley, M. Sori, O. Aharonson, S. Clifford, H. Sizemore, G. Morgan, B. Hartmann, N. Schorghofer, R. Clark, D. Berman, D. Crown, F. Chuang, M. Siegler, E. N. Dobrea, K. Lynch, R. W. Obbard, M. R. Elmaary, D. Fisher, A. Kleinboehl, M. Balme, B. Schmitt, M. Daly, R. C. Ewing, Kenneth E. Herkenhoff, L. Fenton, S. D. Guzewich, M. Koutnik, J. Levy, R. Massey, A. Losiak, V. Eke, D. Goldsby, A. Cross, T. Hager, S. Piqueux, A Kereszturi, K. Seelos, S. Wood, E. Hauber, C. Amos, P. Russell, R. Jaumann, G. Michael, S. Conway, A. Khayat, S. Lewis, G. Luizzi, G. Martinez, K. Mesick, L. Montabone, Johnsson, A. Pankine, C. Phillips-Lander, P. Read, Lauren A. Edgar, K. Zacny, A. McAdam, A. Rutledge, T. Bertrand, J. Widmer, D. Stillman, A. Soto, Z. Yoldi, R. Young, A. Svensson, L. Sam, M. Landis, A. Bhardwaj, M. Chojnacki, E. Kite, P. Thomas, J. Plaut, J. Bapst, S. Milkovich, J. Whiteway, J. Moores, C. Rezza, R. Karimova, I. Mishev, A. Van Brenen, P. Acharya, J. Chesal, A. Pascuzzo, E. Vos, G. Osinski, C. Andres, C. Neisch, S. Hibbard, P. Sinha, J. P. Knightly, S. Cartwright, S. Kounaves, C. Orgel, M. Skidmore, J. MacGregor, R. Staehle, J. Rabassa, C. Gallagher, A. Coronato, A. G. Galofre, J. Wilson, L. McKeown, N. Oliveira, P. Fawdon, U. Gayathri, C. Stuurman, C. Herny, F. Butcher, F. Bernardini, M. Perry, R. Hu, S. Mukherjee, V. Chevrier, M. E. Banks, T. Meng, P. A. Johnson, B. Tober, J. C. Johnson, Ulamsec, J. C. Echaurren, A. Khuller, C. Dinwiddie, S. Adeli, B. L. Henderson, L. R. Lozano, D. Lalich, E. Rivera-Valentín, S. Nerozzi, E. Petersen, F. Foss, R. Lorenz, J. Eigenbrode, M. Day, A. Brown, M. Pajola, O. Karatekin, A. Lucchetti, C. Cesar, C. Newman, T. G. Cave, M. Mischna, M. Patel, P. Streeter, J. C. Stern, C. M. Dundas
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
1. The North Polar Layered Deposits contain thousands of ice layers that record accumulation and climate history for at least several million years, making the most accessible and most complete climate record aside from the Earth’s – and the only one to record the impact of large obliquity shifts. 2. Mars...
Yellowstone Volcano Observatory 2020 annual report
Yellowstone Volcano Observatory
2021, Circular 1482
The Yellowstone Volcano Observatory (YVO) monitors volcanic and hydrothermal activity associated with the Yellowstone magmatic system, conducts research into magmatic processes occurring beneath Yellowstone Caldera, and issues timely warnings and guidance related to potential future geologic hazards. This report summarizes the activities and findings of YVO during the year 2020,...
Asteroid impacts - downwind and downstream effects
Timothy N. Titus, D. G. Robertson, Joel B. Sankey, Larry G. Mastin
2021, Conference Paper, 7th IAA Planetary Defense Conference – PDC 2021
For this abstract, we have selected an impact location, consistent with the PDC2021 initial scenario [1], in the San Juan Mountains, in southwestern Colorado. This is a low-density population area but is part of the watershed system within the Colorado River basin, a major source for water and power for...
The scientific rationale for deployment of a long-lived geophysical network on the Moon
Renee Weber, Clive Neal, Robert E. Grimm, Matthias Grott, Nick Schmerr, Mark Wieczorek, James D. Williams, Bruce Banerdt, Caroline Beghein, Peter Chi, Douglas Currie, Simone Dell’Agnello, Jared Espley, Raphael Garcia, Ian Garrick-Bethell, Heidi Haviland, Stephen Indyk, Catherine L. Johnson, Taichi Kawamura, Sharon Kedar, Philippe Lognonne, Seiichi Nagihara, Yosio Nakamura, Ceri Nunn, Lillian R. Ostrach, Mark Panning, Noah E. Petro, Matthew Siegler, Thomas R. Watters, Kris Zacny, S. Hop Bailey, Maria Banks, Donald Barker, Hannes Bernhardt, Valentin Bickel, Joshua T. Cahill, Jackie Clark, Dani DellaGiustina, Jesse-Lee Dimech, Andrew Dombard, Catherine Elder, Lindy Elkins-Tanton, Marshall Eubanks, Kerri Donaldson Hanna, Jan Harms, Steve Hauck, Lon Hood, Jose Hurtado, Seth Jacobson, Devanshu Jha, James Tuttle Keane, Amir Khan, Walter Kiefer, Martin Knapmeyer, Brigitte Knapmeyer-Endrun, Krishan Khurana, Juan Manuel Lorenzo, Angela Marusiak, Patrick McGovern, Laurent Montesi, Francis Nimmo, Deanna Phillips, Jacob A. Richardson, Charles Shearer, Krista Soderlund, Sean C. Solomon, Tilman Spohn, Eleonore Stutzmann, Sonia Tikoo, Slava Turyshev, Dany Waller, Ryuhei Yamada, Maria Zuber
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
This white paper focuses on the scientific rationale for deploying a global, long-lived network of geophysical instruments on the surface of the Moon to understand the nature and evolution of the lunar interior from the crust to the core....
A Next Generation Lunar Orbiter mission
Timothy Glotch, Lynne Carter, Pamela Clark, Brett W. Denevi, Benjamin T Greenhagen, G. Wes Patterson, Noah E. Petro, Kurt Retherford, Sarah Valencia, Joshua T. Cahill, Ryan Watkins, Kerri Donaldson Hanna, Catherine Elder, Harald Hiesinger, Georgiana Kramer, Timothy Livengood, Heather Meyer, Lillian R. Ostrach, Michael Poston, Morgan Schusterman, Matthew Siegler, Emerson Speyerer, Angela Stickle, Carolyn H. Van der Bogert, Daniel Moriarty, Lisa R. Gaddis
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
The Moon is the scientific foundation for our knowledge of the early evolution and impact history of the terrestrial planets. Over the last decades the lunar science community has made significant progress in addressing key lunar science and exploration goals, while defining many new high-priority scientific questions regarding the formation...
GANGOTRI mission concept on the glacial key to the Amazonian climate of Mars
Suniti Karunatillake, Ali M Bramson, Kris Zacny, Colin M. Dundas, Lujendra Ojha, Oded Aharonson, Eran Vos, Don R Hood, A. Deanne Rogers, Joseph S. Levy, Peter Doran, Kathleen Mandt, Jack Wilson, Emily B Hughes, Heidi Fuqua-Haviland, Jeffrey Moersch, Scott M. Perl, Dewan E. Haque, J. R. Skok, Harish, S. Vijayan, A. Bhardwaj, Brent Christner, Hanna Sizemore, A Kereszturi, Norbert Schorghofer, Kurt Retherford, Paul Niles, Juan Manuel Lorenzo, Katherine Mesick, Heather Franz, Jose Rodriguez-Manfredi, Daniel Coupland, Peter Bertone
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
The GANGOTRI mission concept would investigate in situ the geologic origins of midlatitudinal Martian glaciers, as underlain by Amazonian climate evolution, by riddling the ice with a hybrid thermo-mechanical drill for deep englacial sampling. GANGOTRI would use regolith compositional measurements to characterize ice-regolith interaction, and stable isotope measurements to characterize...
Maximizing the science and resource mapping potential of Orbital VSWIR Spectral measurements of Mars
Scott L. Murchie, Raymond E. Arvidson, Janice L Bishop, Wendy M. Calvin, John Carter, John Christian, Roger N. Clark, Colin M. Dundas, Bethany L. Ehlmann, Valerie K. Fox, Abigail A. Fraeman, Timothy A Goudge, Briony H. N. Horgan, Madison N Hughes, Ellen K Leask, Alfred S. McEwen, John F Mustard, Mario Parente, Kathryn E Powell, Frank P. Seelos, Kimberly D. Seelos, Jesse D Tarnas, Christina E Viviano, James J. Wray
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
The last 16 years witnessed a rapid growth in understanding the composition and aqueous alteration of Mars’ surface from orbital data from the Observatoire pour la Mineralogie, l’Eau, les Glaces et l’Activité (OMEGA) [1] and Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) [2]. Both are sensitive to water-, hydroxyl-, sulfate-,...
Current activity on the Martian surface: A key subject for future exploration
Colin M. Dundas, Shane Byrne, Matthew Chojnacki, Serina Diniega, Ingrid J. Daubar, Christopher W. Hamilton, Candice J. Hansen, Alfred S. McEwen, Ganna Portyankina, Hanna G Sizemore
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
One of the fundamental discoveries in Mars science in the last decade has been the extent and importance of current surface activity. Recent results have shifted our view of Mars from a world where the most interesting geologic events were in the distant past (similar to the Moon) to a...
Mid-latitude ice on Mars: A science target for planetary climate histories and an exploration target for in situ resources
Ali Bramson, Chimira Andres, Jonathan Bapst, Patricio Becerra, Samuel W Courville, Colin M. Dundas, Shannon M Hibbard, John W Holt, Suniti Karunatillake, Aditya Khuller, Michael T. Mellon, Gareth A Morgan, R. W. Obbard, Matthew R Perry, Eric I Petersen, Nathaniel E. Putzig, Hanna G Sizemore, Isaac B. Smith, David E Stillman, Paul Wooster
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
In the last decade, aided by the high-resolution data and long-term monitoring by NASA’s Mars Reconnaissance Orbiter (MRO) and other spacecraft, extensive evidence has emerged supporting the presence of abundant H2O ground ice throughout much of the mid-latitudes of Mars. Growing evidence indicates that much of this ice is relatively...
A critical gap: In situ measurements of surface-atmosphere interactions from outside earth
Serina Diniega, Devon M. Burr, Colin M. Dundas, Brian Jackson, Michael Mischna, Scot Rafkin, Isaac B. Smith, Robert Sullivan, Timothy N. Titus, Nathalie Vriend, Ian J. Walker, Kaj E. Williams
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
This white paper demonstrates five points: (1) The lack of robust measurements of the vertical gradients of natural boundary layers and transport fluxes on other planetary bodies precludes adequate estimation of aeolian and other meteorological processes throughout our Solar System (§1). (2) Thus, there exist critical knowledge gaps within high-priority...
Summary of the final report from the Ice and Climate Evolution Science Analysis group (ICE-SAG)
Serina Diniega, Nathaniel E. Putzig, Shane Byrne, Wendy M. Calvin, Colin M. Dundas, Lori K. Fenton, Paul O. Hayne, David M H Baker, John W Holt, Christine S. Hvidberg, Melinda Kahre, Michael Mischna, Gareth A Morgan, Dorothy Oehler, Ganna Portyankina, A. Deanne Rogers, Hanna G Sizemore, Isaac B. Smith, Alejandro Soto, Leslie Tamppari, Timothy N. Titus, Chris Webster
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
The Ice and Climate Evolution Science Analysis Group (ICE-SAG) was convened by the Mars Exploration Program Analysis Group (MEPAG) in fall 2018, with the aims of (1) identifying and prioritizing fundamental science questions related to the recent and ongoing evolution of Mars volatiles and climate, and (2) exploring new mission...
The Preventing Harassment in Science workshop: Summary and best practices for planetary science and astrobiology
Kristen A. Bennett, Maggie McAdam, Moses Milazzo, Patricia A. Garcia, Jenna L. Shelton, Peggy J. Gardiner, Serina Diniega, Catalina Martinez, Alexandra B. Etheridge, Alicia Rutledge, C. Richey
2021, Report, Planetary science and astrobiology decadal survey 2023-2032
The NASA-funded Preventing Harassment in Science workshop took place in June of 2020. Here we describe the workshop and summarize the best practices for reducing harassment that were discussed. We include a list of recommendations that can be used to take steps towards reducing harassment in...
Widespread Ranavirus and Perkinsea infections in Cuban treefrogs (Osteopilus septentrionalis) invading New Orleans, USA
Net Galt, Matthew S Atkinson, Brad Glorioso, Hardin Waddle, Melanie Litton, Anna E. Savage
2021, Herpetological Conservation and Biology (16) 17-29
Invasive species can negatively impact ecosystems in numerous ways, including vectoring pathogenic organisms. In amphibians, a lineage globally threatened by multiple pathogens, this spread of disease via invasive species could contribute to declines in native populations. The Cuban Treefrog (Osteopilus septentrionalis) is invasive in the southeastern USA. To assess whether...
Effect of temperature on survival of Lost River Suckers with a natural infection of Ichthyobodo spp.
Barbara A. Martin, Summer M. Burdick, Maureen K. Purcell, Rachel L. Powers
2021, North American Journal of Aquaculture (83) 184-191
To compensate for low natural survival of endangered Lost River Suckers Deltistes luxatus, the U.S. Fish and Wildlife Service and the Klamath Tribes have initiated captive rearing programs. We conducted laboratory experiments intended to determine the temperature for optimum growth of juvenile Lost River Suckers; however, due...