Physical Sciences and Mathematics Commons^™

Diagnosis Of The July 6, 2002 Ogallala, Nebraska Flash Flood, David B. Radell, Mark R. Anderson, John W. Stoppkotte, James R. Mccormick

Department of Earth and Atmospheric Sciences: Faculty Publications

During the early morning hours of 6 July 2002, a mesoscale convective system (MCS) traversed southwestern Nebraska and produced more than 40 cm of precipitation, resulting in a flash flood that closed Interstate 80 and caused one fatality near Ogallala, Nebraska. Regional climatology yields that this flash flood ranked first in precipitation amount for a 24 hour period over the past one hundred years. Synoptic and mesoscale features similar to other flash flooding events and conducive to extremely heavy precipitation were in place over the Central Plains, including a weak upper level ridge, high precipitable water values (180% of normal), …

Persistent Near-Bottom Aggregations Of Mesopelagic Animals Along The North Carolina And Virginia Continental Slopes, John V. Gartner Jr., Kenneth J. Sulak, Steve W. Ross, Ann Marie Necaise

United States Geological Survey: Staff Publications

Submersible observations during four missions over the North Carolina and Virginia continental slopes (184–900 m) documented the occurrence of large aggregations of mesopelagic Wshes and macronektonic invertebrates near or on the bottom. Aggregated mesopelagics formed a layer up to tens of meters deep positioned from a few centimeters to 20 m, usually <10 >m, above the substrate. Aggregations were numerically dominated by microvores, notably the myctophid Wsh Ceratoscopelus maderensis and the penaeid shrimp Sergestes arcticus. Consistently present but in relatively lower numbers, were mesopelagic predators, including the paralepidids Notolepis rissoi and Lestidium atlanticum, the eel Nemichthys scolopaceus, the …

Demersal Fishes Associated With Lophelia Pertusa Coral And Hard-Substrate Biotopes On The Continental Slope, Northern Gulf Of Mexico, Kenneth J. Sulak, R. Allen Brooks, Kirsten E. Luke, April D. Norem, Michael Randall, Andrew J. Quaid, George E. Yeargin, Jana M. Miller, William M. Harden, John H. Caruso, Steve W. Ross

United States Geological Survey: Staff Publications

The demersal fish fauna of Lophelia pertusa (Linnaeus, 1758) coral reefs and associated hard-bottom biotopes was investigated at two depth horizons in the northern Gulf of Mexico using a manned submersible and remote sampling. The Viosca Knoll fauna consisted of at least 53 demersal fish species, 37 of which were documented by submersible video. On the 325 m horizon, dominant taxa determined from frame-by-frame video analysis included Stromateidae, Serranidae, Trachichthyidae, Congridae, Scorpaenidae, and Gadiformes. On the 500 m horizon, large mobile visual macrocarnivores of families Stromateidae and Serranidae dropped out, while a zeiform microcarnivore assumed importance on reef “Thicket” biotope, …

Drought Scape- Fall 2007, The National Drought Mitigation Center

Droughtscape, Quarterly Newsletter of NDMC, 2007-

Fall 2007 Outlook

Diverse Impacts Reported in Summer of 2007

Decadal Climate Cycles Hold Predictive Potential

Drought Experts Take Roadmap to Congress

NDMC Research Updates

Droughtscape- Summer 2007, The National Drought Mitigation Center

Droughtscape, Quarterly Newsletter of NDMC, 2007-

Summer 07 Outlook

Hayes Named Director of NDMC

NDMC & UN Plan for Drought

Book Review: The Worst Hard Time

Drought Tools Workshops Underway

U.S. Drought Monitor Forum October 10-11, 2007 Portland, Oregon

Analysis Of Time-Series Modis 250 M Vegetation Index Data For Crop Classification In The U.S. Central Great Plains, Brian D. Wardlow, Stephen L. Egbert, Jude H. Kastens

Drought Mitigation Center: Faculty Publications

The global environmental change research community requires improved and up-to-date land use/land cover (LULC) datasets at regional to global scales to support a variety of science and policy applications. Considerable strides have been made to improve large-area LULC datasets, but little emphasis has been placed on thematically detailed crop mapping, despite the considerable influence of management activities in the cropland sector on various environmental processes and the economy. Time-series MODIS 250 m Vegetation Index (VI) datasets hold considerable promise for largearea crop mapping in an agriculturally intensive region such as the U.S. Central Great Plains, given their global coverage, intermediate …

Droughtscape- Spring 2007, The National Drought Mitigation Center

Droughtscape, Quarterly Newsletter of NDMC, 2007-

2007 Spring Drought Outlook & Winter Summary

VegDRI Expands to 15 States, Refines Views

DroughtScape

State Spotlight: Utah

International Panel Foresees Drought as Part of Climate Change

NIDIS Portal Advancing

Frequency Of Sublethal Injury In A Deepwater Ophiuroid, Ophiacantha Bidentata, An Important Component Of Western Atlantic Lophelia Reef Communities, R. Allen Brooks, Martha S. Nizinski, Steve W. Ross, Kenneth J. Sulak

United States Geological Survey: Staff Publications

The occurrence and relative abundance of tissue (arm) regeneration in the ophiuroid, Ophiacantha bidentata (Retzius), was examined in individuals collected primarily among colonies of the deep-water coral Lophelia pertusa off the southeastern United States. Seven deep-water coral sites (384–756 m), located between Cape Lookout, NC, and Cape Canaveral, FL, were sampled in June 2004 using a manned submersible. The presence of regenerative tissue was evaluated by visual inspection of each individual ophiuroid, and the proportion of regenerating arms per individual was examined relative to size of individual, geographic location, and depth of collection. Ophiacantha bidentata, the dominant brittle star collected, …

Agricultural Climatology, Kenneth G. Hubbard

HPRCC Personnel Publications

With the diversification of the U.S. economy over the past century, agriculture has changed. We can say the farm sizes have increased over time, the number of farmers and those employed in farming have decreased over time, and as the economy has grown the relative contribution of agriculture to the total economy has decreased due to growth in other sectors. The farm prices have not changed significantly over many years while costs for energy, machinery, and land have generally increased. The combination of these factors has generally narrowed the profit margin and the highest productivity will no longer ensure the …

Droughtscape- Winter 2007, Kelly Smith

Droughtscape, Quarterly Newsletter of NDMC, 2007-

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Policy Update: NIDIS is Law. What’s Next?

What Would You Like to See?

TX, OK, Plains, Southwest Hardest Hit in 2006

Climatologically Speaking, How Bad Was It?

State Spotlight: Arizona

Drought Decision-Support Tools Evolving

New Insights Into Marine Migration And Winter Habitat Of Gulf Sturgeon, Randy E. Edwards, Frank M. Parauka, Kenneth J. Sulak

United States Geological Survey: Staff Publications

Migrations and movements of Gulf sturgeon Acipenser oxyrinchus desotoi were determined using satellite pop-up archival transmitting (PAT) tags and acoustic telemetry. Adult Gulf sturgeon from four rivers in northwestern Florida were caught with gill nets and were tagged with PAT and acoustic tags in the fall of 2001 and 2002. PAT tags were programmed to release in early February 2002 and 2003 to provide information about location of late-winter marine habitats. However, only 5 of 25 provided meaningful location information. Three of the PAT-tagged fish were relocated acoustically near the PAT tag pop-up locations, one of which was in Choctawhatchee …

Hydrologic Connectivity And The Contribution Of Stream Headwaters To Ecological Integrity At Regional Scales, Mary C. Freeman, Catherine M. Pringle, C. Rhett Jackson

United States Geological Survey: Staff Publications

Cumulatively, headwater streams contribute to maintaining hydrologic connectivity and ecosystem integrity at regional scales. Hydrologic connectivity is the water-mediated transport of matter, energy and organisms within or between elements of the hydrologic cycle. Headwater streams compose over two-thirds of total stream length in a typical river drainage and directly connect the upland and riparian landscape to the rest of the stream ecosystem. Altering headwater streams, e.g., by channelization, diversion through pipes, impoundment and burial, modifies fluxes between uplands and downstream river segments and eliminates distinctive habitats. The large-scale ecological effects of altering headwaters are amplified by land uses that alter …

Butterfly Responses To Prairie Restoration Through Fire And Grazing, Jennifer A. Vogel, Diane M. Debinski, Rolf R. Koford, James R. Miller

United States Geological Survey: Staff Publications

The development of land for modern agriculture has resulted in losses of native prairie habitat. The small, isolated patches of prairie habitat that remain are threatened by fire suppression, overgrazing, and invasion by non-native species. We evaluated the effects of three restoration practices (grazing only, burning only, and burning and grazing) on the vegetation characteristics and butterfly communities of remnant prairies. Total butterfly abundance was highest on prairies that were managed with burning and grazing and lowest on those that were only burned. Butterfly species richness did not differ among any of the restoration practices. Butterfly species diversity was highest …

Adaptive Data-Driven Models For Estimating Carbon Fluxes In The Northern Great Plains, Bruce K. Wylie, Eugene A. Fosnight, Tagir G. Gilmanov, Albert B. Frank, Jack A. Morgan, Marshall R. Haferkamp, Tilden P. Meyers

United States Geological Survey: Staff Publications

Rangeland carbon fluxes are highly variable in both space and time. Given the expansive areas of rangelands, how rangelands respond to climatic variation, management, and soil potential is important to understanding carbon dynamics. Rangeland carbon fluxes associated with Net Ecosystem Exchange (NEE) were measured from multiple year data sets at five flux tower locations in the Northern Great Plains. These flux tower measurements were combined with 1-km² spatial data sets of Photosynthetically Active Radiation (PAR), Normalized Difference Vegetation Index (NDVI), temperature, precipitation, seasonal NDVI metrics, and soil characteristics. Flux tower measurements were used to train and select variables for …

Societal Adaptation To Decadal Climate Variability In The United States, Norman J. Rosenberg, Vikram M. Mehta, J Rolf Olsen, Hans Von Storch, Robert G. Varady, Michael J. Hayes, Donald A. Wilhite

US Army Corps of Engineers

The search for evidence of decadal climatic variability (DCV) has a very long history. In the past decade, a research community has coalesced around a series of roughly biennial workshops that have emphasized description of past DCV events; their causes and their "teleconnections" responsible for droughts, floods, and warm and cold spells around the world; and recently, the predictability of DCV events. Researchers studying climate change put great emphasis on prospective impacts, but the DCV community has yet to do so. To begin rectifying this deficiency, a short but ambitious workshop was convened in Waikoloa, near Kona, Hawaii, from 26-28 …

Microsatellite Loci For Distinguishing Spotted Owls (Strix Occidentalis), Barred Owls (Strix Varia), And Their Hybrids, W. Chris Funk, Thomas D. Mullins, Eric D. Forsman, Susan M. Haig

United States Geological Survey: Staff Publications

We identified four diagnostic microsatellite loci that distinguish spotted owls (Strix occidentalis), barred owls (Strix varia), F₁ hybrids and backcrosses. Thirty-four out of 52 loci tested (65.4%) successfully amplified, and four of these loci (11.8%) had allele sizes that did not overlap between spotted and barred owls. The probability of correctly identifying a backcross with these four loci is 0.875. Genotyping potential hybrid owls with these markers revealed that field identifications were often wrong. Given the difficulty of identifying hybrids in the field, these markers will be useful for hybrid identification, law enforcement and spotted …

Possible Impacts Of Early-11th-, Middle-12th-, And Late-13th-Century Droughts On Western Native Americans And The Mississippian Cahokians, Larry V. Benson, Michael S. Berry, Edward A. Jolie, Jerry D. Spangler, David W. Stahle, Eugene M. Hattori

United States Geological Survey: Staff Publications

One or more of three intense and persistent droughts impacted some Native American cultures in the early-11th, middle-12th and late- 13th centuries, including the Anasazi, Fremont, Lovelock, and Mississippian (Cahokian) prehistorical cultures. Tree-ring-based reconstructions of precipitation and temperature indicate that warm drought periods occurred between AD 990 and 1060, AD 1135 and 1170, and AD 1276 and 1297. These droughts occurred during minima in the Pacific Decadal Oscillation and may have been associated with positive values of the Atlantic Multidecadal Oscillation. Each of the Native American cultures was supported, to a greater or lesser degree, by precipitation-dependent resources. Both the …

Hydrologic Connectivity And The Contribution Of Stream Headwaters To Ecological Integrity At Regional Scales1, Mary C. Freeman, Catherine M. Pringle, C. Rhett Jackson

United States Geological Survey: Staff Publications

Cumulatively, headwater streams contribute to maintaining hydrologic connectivity and ecosystem integrity at regional scales. Hydrologic connectivity is the water-mediated transport of matter, energy and organisms within or between elements of the hydrologic cycle. Headwater streams compose over two-thirds of total stream length in a typical river drainage and directly connect the upland and riparian landscape to the rest of the stream ecosystem. Altering headwater streams, e.g., by channelization, diversion through pipes, impoundment and burial, modifies fluxes between uplands and downstream river segments and eliminates distinctive habitats. The large-scale ecological effects of altering headwaters are amplified by land uses that alter …

Loess Deposits, Origins And Properties, Daniel R. Muhs

United States Geological Survey: Staff Publications

Loess is an eolian (windblown) sediment that is an important archive of Quaternary climate changes. It may provide one of the most complete terrestrial records of interglacial–glacial cycles. Loess is unusual as a record of Quaternary climate change because it is one of the few sediments that is deposited directly from the atmosphere. Thus, it is a geologic deposit that contains a record of atmospheric circulation and can be used to reconstruct synoptic-scale paleoclimatology. Loess is also unusual in that it can be dated directly using ‘trapped electron’ or luminescence methods that require only the sediment itself. Commonly, loess deposits …

Sexual Selection Drives Speciation In An Amazonian Frog, Kathryn E. Boul, W. Chris Funk, Catherine R. Darst, David C. Cannatella, Michael J. Ryan

United States Geological Survey: Staff Publications

One proposed mechanism of speciation is divergent sexual selection, whereby divergence in female preferences and male signals results in behavioural isolation. Despite the appeal of this hypothesis, evidence for it remains inconclusive. Here, we present several lines of evidence that sexual selection is driving behavioural isolation and speciation among populations of an Amazonian frog (Physalaemus petersi). First, sexual selection has promoted divergence in male mating calls and female preferences for calls between neighbouring populations, resulting in strong behavioural isolation. Second, phylogenetic analysis indicates that populations have become fixed for alternative call types several times throughout the species’ range, …

Dune Fields: Mid-Latitudes, J. Sun, Daniel R. Muhs

United States Geological Survey: Staff Publications

Large dune fields, or sand seas, are landscapes often thought to be found only in deserts beneath the great, subtropical high-pressure zones, where subsiding air suppresses rainfall. Dune fields are also quite common in mid-latitude regions, to the north and south of subtropical deserts (Fig. 1). Two major characteristics distinguish many mid-latitude dune fields from the sand seas of lower latitudes. One difference is that many of those in mid-latitudes are in semiarid, rather than arid climates, and therefore are not presently active. In this article, ‘active’ refers to eolian sand bodies that are not covered with vegetation, and where …

Evaluation And Comparison Of Gross Primary Production Estimates For The Northern Great Plains Grasslands, Li Zhang, Bruce K. Wylie, Thomas Loveland, Eugene A. Fosnight, Larry L. Tieszen, Lei Ji, Tagir G. Gilmanov

United States Geological Survey: Staff Publications

Two spatially-explicit estimates of gross primary production (GPP) are available for the Northern Great Plains. An empirical piecewise regression (PWR) GPP model was developed from flux tower measurements to map carbon flux across the region. The Moderate Resolution Imaging Spectrometer (MODIS) GPP model is a process-based model that uses flux tower data to calibrate its parameters. Verification and comparison of the regional PWR GPP and the global MODIS GPP are important for the modeling of grassland carbon flux. This study compared GPP estimates from PWR and MODIS models with five towers in the grasslands. Among them, PWR GPP and MODIS …

Conservation Genetics Of Snowy Plovers (Charadrius Alexandrinus) In The Western Hemisphere: Population Genetic Structure And Delineation Of Subspecies, W. Chris Funk, Thomas D. Mullins, Susan M. Haig

United States Geological Survey: Staff Publications

We examined the genetic structure of snowy plovers (Charadrius alexandrinus) in North America, the Caribbean, and the west coast of South America to quantify variation within and among breeding areas and to test the validity of three previously recognized subspecies. Sequences (676 bp) from domains I and II of the mitochondrial control region were analyzed for 166 snowy plovers from 20 breeding areas. Variation was also examined at 10 microsatellite loci for 144 snowy plovers from 14 breeding areas. The mtDNA and microsatellite data provided strong evidence that the Puerto Rican breeding group is genetically divergent from sites …