Regions

Southwest

Regions L2 Landing Page Tabs

Filter Total Items: 2,184
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Year Published: 2018

Revised recommended methods for analyzing crater size-frequency distributions

Impact crater populations crucially help us to understand solar system dynamics, planetary surface histories, and surface modification processes. A single previous effort to standardize how crater data are displayed in graphs, tables, and archives, was in a 1978 NASA report by the Crater Analysis Techniques Working Group, published in 1979 in...

Robbins, Stuart J.; Riggs, Jamie D.; Weaver, Brian P.; Bierhaus, Edward B.; Chapman, Clark R.; Kirchoff, Michelle R.; Singer, Kelsi N.; Gaddis, Lisa
Robbins, S.J., J.D. Riggs, B.P. Weaver, E.B. Bierhaus, C.R. Chapman, M.R. Kirchoff, K.N. Singer and L.R. Gaddis, 2018, Revised Recommended Methods for Analyzing Crater Size-Frequency Distributions, Meteoritics and Planetary Science, 53, Nr 4, 891-931.

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Year Published: 2018

Detecting geothermal anomalies and evaluating LST geothermal component by combining thermal remote sensing time series and land surface model data

This paper explores for the first time the possibilities to use two land surface temperature (LST) time series of different origins (geostationary Meteosat Second Generation satellite data and Noah land surface modelling, LSM), to detect geothermal anomalies and extract the geothermal component of LST, the LSTgt. We hypothesize that in geothermal...

Romaguera, Mireia; Vaughan, R. Greg; Ettema, J.; Izquierdo-Verdiguier, E.; Hecker, C. A.; van der Meer, F.D.

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Year Published: 2018

Quantifying postfire aeolian sediment transport using rare earth element tracers

Grasslands, which provide fundamental ecosystem services in many arid and semiarid regions of the world, are undergoing rapid increases in fire activity and are highly susceptible to postfire-accelerated soil erosion by wind. A quantitative assessment of physical processes that integrates fire-wind erosion feedbacks is therefore needed relative to...

Dukes, David; Gonzales, Howell B.; Ravi, Sujith; Grandstaff, David E.; Van Pelt, R. Scott; Li, Junran; Wang, Guan; Sankey, Joel B.
Dukes, D., Gonzales, H.B., Ravi, S., Grandstaff, D.E., Van Pelt, R.S., Li, J., Wang, G., and Sankey, J.B., 2018, Quantifying Postfire Aeolian Sediment Transport Using Rare Earth Element Tracers: Journal of Geophysical Research Biogeosciences, v. 123, no. 1, p. 288–299, http://dx.doi.org/10.1002/2017JG004284.

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Year Published: 2018

The geomorphic legacy of water and erosion control structures in a semiarid rangeland watershed

Control over water supply and distribution is critical for agriculture in drylands where manipulating surface runoff often serves the dual purpose of erosion control. However, little is known of the geomorphic impacts and legacy effects of rangeland water manipulation infrastructure, especially if not maintained. This study investigated the...

Nichols, Mary H.; Magirl, Christopher S.; Sayre, N.F.; Shaw, Jeremy R.
Nichols, M. H., Magirl, C., Sayre, N. F., and Shaw, J. R. (2017) The geomorphic legacy of water and erosion control structures in a semiarid rangeland watershed. Earth Surf. Process. Landforms, doi: 10.1002/esp.4287.

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Year Published: 2018

Viscous relaxation as a prerequisite for tectonic resurfacing on Ganymede: Insights from numerical models of lithospheric extension

Ganymede’s bright terrain formed during a near-global resurfacing event (or events) that produced both heavily tectonized and relatively smooth terrains. The mechanism(s) by which resurfacing occurred on Ganymede (e.g., cryovolcanic or tectonic), and the relationship between the older, dark and the younger, bright terrain are fundamental to...

Bland, Michael T.; McKinnon, William B.

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Year Published: 2018

6th international conference on Mars polar science and exploration: Conference summary and five top questions

We provide a historical context of the International Conference on Mars Polar Science and Exploration and summarize the proceedings from the 6th iteration of this meeting. In particular, we identify five key Mars polar science questions based primarily on presentations and discussions at the conference and discuss the overlap between some of those...

Smith, Isaac B.; Diniega, Serina; Beaty, David W.; Thorsteinsson, Thorsteinn; Becerra, Patricio; Bramson, Ali; Clifford, Stephen M.; Hvidberg, Christine S.; Portyankina, Ganna; Piqueux, Sylvain; Spiga, Aymeric; Titus, Timothy N.
Isaac B. Smith, Serina Diniega, David W. Beaty, Thorsteinn Thorsteinsson, Patricio Becerra, Ali M. Bramson, Stephen M. Clifford, Christine S. Hvidberg, Ganna Portyankina, Sylvain Piqueux, Aymeric Spiga, Timothy N. Titus, 6th international conference on Mars polar science and exploration: Conference summary and five top questions, In Icarus, 2017, , ISSN 0019-1035, https://doi.org/10.1016/j.icarus.2017.06.027.

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Year Published: 2018

Variability in eddy sandbar dynamics during two decades of controlled flooding of the Colorado River in the Grand Canyon

Sandbars are iconic features of the Colorado River in the Grand Canyon, Arizona, U.S.A. Following completion of Glen Canyon Dam in 1963, sediment deficit conditions caused erosion of eddy sandbars throughout much of the 360 km study reach downstream from the dam. Controlled floods in 1996, 2004, and 2008 demonstrated that sand on the channel...

Mueller, Erich R.; Grams, Paul E.; Hazel, Joseph E.; Schmidt, John C.
Mueller, E.R., Grams, P.E., Hazel Jr., J.E., and Schmidt, J.C., 2017, in press, Variability in eddy sandbar dynamics during two decades of controlled flooding of the Colorado River in Grand Canyon: Sedimentary Geology, v. (online), https://doi.org/10.1016/j.sedgeo.2017.11.007.

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Year Published: 2018

Estimating disperser abundance using open population models that incorporate data from continuous detection PIT arrays

Autonomous passive integrated transponder (PIT) tag antenna systems continuously detect individually marked organisms at one or more fixed points over long time periods. Estimating abundance using data from autonomous antennae can be challenging, because these systems do not detect unmarked individuals. Here we pair PIT antennae data from a...

Dzul, Maria C.; Yackulic, Charles B.; Korman, Josh
Dzul, M.C., Yackulic, C.B., and Korman, J., 2017, Estimating disperser abundance using open population models that incorporate data from continuous detection PIT arrays: Canadian Journal of Fisheries and Aquatic Sciences, v. (online), https://doi.org/10.1139/cjfas-2017-0304.

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Year Published: 2018

Riparian bird density decline in response to biocontrol of Tamarix from riparian ecosystems along the Dolores River in SW Colorado, USA

Biocontrol of invasive tamarisk (Tamarix spp.) in the arid Southwest using the introduced tamarisk beetle (Diorhabda elongata) has been hypothesized to negatively affect some breeding bird species, but no studies to date have documented the effects of beetle-induced defoliation on riparian bird abundance. We assessed the effects of tamarisk...

Darrah, Abigail J.; van Riper, Charles
Darrah, A.J., and van Riper III, C., 2017, Riparian bird density decline in response to biocontrol of Tamarix from riparian ecosystems along the Dolores River in SW Colorado, USA: Biological Invasions, v. (online), https://doi.org/10.1007/s10530-017-1569-z.

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Year Published: 2018

Landscape-scale processes influence riparian plant composition along a regulated river

Hierarchical frameworks are useful constructs when exploring landscape- and local-scale factors affecting patterns of vegetation in riparian areas. In drylands, which have steep environmental gradients and high habitat heterogeneity, landscape-scale variables, such as climate, can change rapidly along a river's course, affecting the relative...

Palmquist, Emily C.; Ralston, Barbara; Merritt, David M.; Shafroth, Patrick B.
Palmquist, E.C., Ralston, B.E., Merritt, D.M., and Shafroth, P.B., 2017, in press, Landscape-scale processes influence riparian plant composition along a regulated river: Journal of Arid Environments, v. (online), https://doi.org/10.1016/j.jaridenv.2017.10.001.

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Year Published: 2018

The effects of snow and salt on ice table stability in University Valley, Antarctica

The Antarctic Dry Valleys represent a unique environment where it is possible to study dry permafrost overlaying an ice-rich permafrost. In this paper, two opposing mechanisms for ice table stability in University Valley are addressed: i) diffusive recharge via thin seasonal snow deposits and ii) desiccation via salt deposits in the upper soil...

Williams, Kaj; Heldmann, Jennifer L.; McKay, Christopher P.; Mellon, Michael T.
Williams, K., Heldmann, J., Mckay, C., & Mellon, M. (2017). The effects of snow and salt on ice table stability in University Valley, Antarctica. Antarctic Science, 1-12. doi:10.1017/S0954102017000402

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Year Published: 2018

Improving predictions of tropical forest response to climate change through integration of field studies and ecosystem modeling

Tropical forests play a critical role in carbon and water cycles at a global scale. Rapid climate change is anticipated in tropical regions over the coming decades and, under a warmer and drier climate, tropical forests are likely to be net sources of carbon rather than sinks. However, our understanding of tropical forest response and feedback to...

Feng, Xiaohui; Uriarte, María; González, Grizelle; Reed, Sasha C.; Thompson, Jill; Zimmerman, Jess K.; Murphy, Lora
Feng, X., Uriarte, M., Gonzalez, G., Reed, S., Thompson, J., Zimmerman, J.K., and Murphy, L., 2017, Improving predictions of tropical forest response to climate change through integration of field studies and ecosystem modeling: Global Change Biology, v. (online), http://dx.doi.org/ 10.1111/gcb.13863.

Filter Total Items: 239
Image: Black Skimmer Nesting Colony
July 12, 2009

Black Skimmer Nesting Colony

Birds found in and around the Salton Sea, California.

Attribution: Southwest
Image: Black Skimmer Nesting Colony
July 12, 2009

Black Skimmer Nesting Colony

Birds found in and around the Salton Sea, California.

Attribution: Southwest
Image: Black Skimmer
July 12, 2009

Black Skimmer

Birds found in and around the Salton Sea, California.

Attribution: Southwest
Image: White-faced Ibis
July 2, 2009

White-faced Ibis

Birds found in and around the Salton Sea, California.

Attribution: Southwest
Image: California Brown Pelicans
June 11, 2009

California Brown Pelicans

Birds found in and around the Salton Sea, California.

Attribution: Southwest
Image: American Avocet Attack
June 11, 2009

American Avocet Attack

Birds found in and around the Salton Sea, California.

Attribution: Southwest
Image: California Brown Pelicans
June 11, 2009

California Brown Pelicans

Birds found in and around the Salton Sea, California.

Attribution: Southwest
Image: California Brown Pelicans
June 11, 2009

California Brown Pelicans

Birds found in and around the Salton Sea, California.

Attribution: Southwest
Image: An American Avocet and Black Skimmer
June 11, 2009

An American Avocet and Black Skimmer

Birds found in and around the Salton Sea, California.

Attribution: Southwest
Image: Gull-billed Tern
June 11, 2009

Gull-billed Tern

Birds found in and around the Salton Sea, California.

Attribution: Southwest
Image: Gull-billed Tern
June 11, 2009

Gull-billed Tern

Birds found in and around the Salton Sea, California.

Attribution: Southwest
Image: Snowy Egret, Great Blue Heron and Brown Pelican
June 11, 2009

Snowy Egret, Great Blue Heron and Brown Pelican at the Salton Sea

Birds found in and around the Salton Sea, California.

Attribution: Southwest

Nine USGS Science Centers are administered by the Pacific Regional office, which is headquartered in Sacramento, California.