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2011

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Articles 31 - 60 of 478

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Production And Fate Of Transparent Exopolymer Particles In The Ocean, Oliver Wurl, Lisa Miller, Svein Vagle Dec 2011

Production And Fate Of Transparent Exopolymer Particles In The Ocean, Oliver Wurl, Lisa Miller, Svein Vagle

OES Faculty Publications

The production and fate of transparent exopolymer particles (TEP) have been investigated in various oceanic regions (tropical, temperate, and polar), from the sea surface microlayer (SML) to the deep ocean. Accumulation of TEP within the mixed layer was observed even in the absence of phytoplankton blooms, indicating abiotic processes are important in TEP production. The abiotic TEP aggregation rates measured in the tropical and temperate North Pacific and the Arctic Ocean averaged between 8 and 12 μmol C L-1 d-1. Depth profiles from under sea ice in the Arctic revealed the highest TEP concentrations, potentially released by …


Environmental Influences On Juvenile Fish Abundances In A River-Dominated Coastal System, Laure Carassou, Brian Dzwonkowski, Frank J. Hernandez, Jr., Sean P. Powers, William M. Graham, Kyeong Park, John Mareska Dec 2011

Environmental Influences On Juvenile Fish Abundances In A River-Dominated Coastal System, Laure Carassou, Brian Dzwonkowski, Frank J. Hernandez, Jr., Sean P. Powers, William M. Graham, Kyeong Park, John Mareska

University Faculty and Staff Publications

We investigated the influence of climatic and environmental factors on variations in juvenile abundances of marine fishes in a river-dominated coastal system of the north-central Gulf of Mexico, where an elevated primary productivity sustains fisheries of high economic importance. Fish were collected monthly with an otter trawl at three stations near Mobile Bay from 1982 to 2007. Fish sizes were used to isolate juvenile stages within the data set, and monthly patterns in juvenile fish abundance and size were then used to identify seasonal peaks for each species. The average numbers of juvenile fish collected during these seasonal peaks in …


Spring Migration Of Mallards From Arkansas As Determined By Satellite Telemetry, David George Krementz, Kwasi Asante, Luke W. Naylor Dec 2011

Spring Migration Of Mallards From Arkansas As Determined By Satellite Telemetry, David George Krementz, Kwasi Asante, Luke W. Naylor

United States Geological Survey: Staff Publications

We used satellite telemetry to document spring migration phenology, routes, stopover regions, and nesting sites of mallards Anas platyrhynchos marked in Arkansas during the winters of 2004–2007. Of the 143 marked mallards that migrated from Arkansas, they did so, on average, by mid-March. Mallards flew over the Missouri Ozarks and 42% made an initial stopover in Missouri, where they used areas that had larger rivers (Mississippi River, Missouri River) embedded in an agricultural landscape. From this stopover region they either migrated directly to the Prairie Pothole Region (PPR) or they migrated north to Minnesota where they either moved next to …


Surface Water Characteristics Of The Weaber Plain And Lower Keep River Catchments: Data Review And Preliminary Results, D L. Bennett, Richard J. George Dr Dec 2011

Surface Water Characteristics Of The Weaber Plain And Lower Keep River Catchments: Data Review And Preliminary Results, D L. Bennett, Richard J. George Dr

Resource management technical reports

In 2008, the Ord Irrigation Expansion Project was approved by the Western Australian Government to develop irrigated agriculture on the Weaber Plain.

An important concern is the effect the Weaber Plain agricultural development may have on the water quality of the downstream Border Creek and Keep River

This report assembles and reviews all available physico-chemical water quality data for the lower Keep River and Border Creek systems and presents data from the initial year of a targeted baseline monitoring program (June 2010 – June 2013).


Groundwater Chemistry Of The Weaber Plain: Preliminary Results, Adam Lillicrap, Paul Raper, Richard J. George Dr, D L. Bennett Dec 2011

Groundwater Chemistry Of The Weaber Plain: Preliminary Results, Adam Lillicrap, Paul Raper, Richard J. George Dr, D L. Bennett

Resource management technical reports

In 2008, the Ord Irrigation Expansion Project was approved by the Western Australian Government to develop irrigated agriculture on the Weaber Plain. Construction of the M2 supply channel connecting the ORIA and the Weaber Plain, and the final period of irrigation design, environmental management and related approval processes, commenced later in 2009. This process followed a protracted period of public and private industry planning and environmental assessment (Kinhill 2000). This report summarises an analysis of groundwater salinity trends on the Ivanhoe and Weaber plains and the preliminary results of an intensive water-quality sampling program carried out in 2010 as part …


Ensemble Methods For Dynamic Data Assimilation Of Chemical Observations In Atmospheric Models, Adrian Sandu, Emil Constantinescu, Gregory R. Carmichael, Tianfeng Chai, Dacian Daescu, John H. Seinfeld Dec 2011

Ensemble Methods For Dynamic Data Assimilation Of Chemical Observations In Atmospheric Models, Adrian Sandu, Emil Constantinescu, Gregory R. Carmichael, Tianfeng Chai, Dacian Daescu, John H. Seinfeld

Mathematics and Statistics Faculty Publications and Presentations

The task of providing an optimal analysis of the state of the atmosphere requires the development of dynamic data-driven systems (DDDAS) that efficiently integrate the observational data and the models. Data assimilation, the dynamic incorporation of additional data into an executing application, is an essential DDDAS concept with wide applicability. In this paper we discuss practical aspects of nonlinear ensemble Kalman data assimilation applied to atmospheric chemical transport models. We highlight the challenges encountered in this approach such as filter divergence and spurious corrections, and propose solutions to overcome them, such as background covariance inflation and filter localization. The predictability …


Concept Tests For A New Wire Flying Vehicle Designed To Achieve High Horizontal Resolution Profiling In Deep Water, Chris Roman, Dave Hebert Dec 2011

Concept Tests For A New Wire Flying Vehicle Designed To Achieve High Horizontal Resolution Profiling In Deep Water, Chris Roman, Dave Hebert

Graduate School of Oceanography Faculty Publications

Efficiently profiling the water column to achieve both high vertical and horizontal resolution from a moving vessel in deep water is difficult. Current solutions, such as CTD tow-yos, moving vessel profilers, and undulating tow bodies, are limited by ship speed or water depth. As a consequence, it is difficult to obtain oceanographic sections with sufficient resolution to identify many relevant scales over the deeper sections of the water column. This paper presents a new concept for a profiling vehicle that slides up and down a towed wire in a controlled manner using the lift created by wing foils. The wings …


Hydroclimatic Forecasting In The Western United States Using Paleoclimate Reconstructions And Data-Driven Models, Christopher Allen Carrier Dec 2011

Hydroclimatic Forecasting In The Western United States Using Paleoclimate Reconstructions And Data-Driven Models, Christopher Allen Carrier

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis investigated climate variability and their associated hydrologic responses in the western United States. The western United States faces the problem of water scarcity, where the management and mitigation of available water supplies are further complicated by climate variability. Climate variability associated with the phases of oceanic-atmospheric oscillations has been shown to influence streamflow and precipitation, where predictive relationships have led to the possibility of producing long-range forecasts. Based on literature review, four oceanic-atmospheric oscillation indices were identified in having the most prominent influence over the western United States including the El Niño - Southern Oscillation (ENSO), Pacific Decadal …


A Landscape Approach To Late Prehistoric Settlement And Subsistence Patterns In The Mojave Sink, Tiffany Ann Thomas Dec 2011

A Landscape Approach To Late Prehistoric Settlement And Subsistence Patterns In The Mojave Sink, Tiffany Ann Thomas

UNLV Theses, Dissertations, Professional Papers, and Capstones

The environment of the Late Prehistoric period (1200 A.D. to Historic Contact) Mojave Sink was wetter than modern conditions. The settlement and subsistence patterns of the occupants of the region during this period were driven by the availability of water, subsistence resources, raw material sources, and tradition. These people utilized the regional landscape based upon the seasonal availability of these resources. Supplemental agricultural production has been proposed for the Mojave River Delta due to the more favorable environmental conditions of this period. If agriculture was being practiced it would have affected the regional land-use patterns. For this thesis I propose …


Changing Climatic Conditions In The Colorado River Basin: Implications For Water Resources Management In The Las Vegas Valley, Srijana Dawadi Dec 2011

Changing Climatic Conditions In The Colorado River Basin: Implications For Water Resources Management In The Las Vegas Valley, Srijana Dawadi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Climate change affects the water available in a region. It also affects the water demand, because of the increase in temperature. A system dynamics model was developed for the Colorado River Basin (CRB), operating at a monthly time scale, to assess the potential impacts of climate change on streamflow in the Colorado River and its subsequent impact on the water resources management in the Las Vegas Valley (LVV). The effect of climate change on streamflow was evaluated using 16 global climate model outputs for 3 emission scenarios, also referenced in the Inter-Governmental Panel on Climate Change Fourth Assessment Report. Risk …


The Effects Of Evapotranspiration Upon Recharge Using The Stable Isotopes Of Oxygen And Hydrogen In The Carbonate Aquifers Of The Cumberland Plateau In Southeast Kentucky, Lee J. Florea Nov 2011

The Effects Of Evapotranspiration Upon Recharge Using The Stable Isotopes Of Oxygen And Hydrogen In The Carbonate Aquifers Of The Cumberland Plateau In Southeast Kentucky, Lee J. Florea

Lee J Florea, PhD, P.G.

In this brief manuscript, we consider the variation of the stable isotopes of oxygen, δ18O, and hydrogen, δ2H, in samples collected during 2010 and 2011 from precipitation and shallow groundwater along the Cumberland Plateau of southeast Kentucky. These data from the 1,900-ha Redmond Creek karst aquifer lend insight into the source and timing of recharge to shallow groundwater in the epigenic karst of the U.S midcontinent. Specifically, we find that only 43% of precipitation remains as potential recharge after accounting for evapotranspiration, and 85% of this potential recharge occurs during only four two-week sampling periods. The isotopic composition of precipitation …


Spatial And Temporal Variations In The Air-Sea Carbon Dioxide Fluxes Of Florida Bay, Christopher Michael Dufore Nov 2011

Spatial And Temporal Variations In The Air-Sea Carbon Dioxide Fluxes Of Florida Bay, Christopher Michael Dufore

USF Tampa Graduate Theses and Dissertations

The flux of CO2 between the ocean and the atmosphere is an important measure in determining local, global, and regional, as well as short term and long term carbon budgets. In this study, air-sea CO2 fluxes measured using a floating chamber were used to examine the spatial and temporal variability of CO2 fluxes in Florida Bay. Measurements of dissolved inorganic carbon and total alkalinity obtained concurrently with chamber measurements of CO2 flux allowed calculation of ΔpCO2 from flux measurements obtained at zero wind velocity. Floating chamber measurements of ΔpCO2 were subsequently coupled with wind speed data to provide a simple …


Gravity Wave Characteristics From Oh Airglow Imager Over Maui, Alan Z. Liu, Xian Lu, Zhenhua Li, Gary R. Swenson, Steven Franke Nov 2011

Gravity Wave Characteristics From Oh Airglow Imager Over Maui, Alan Z. Liu, Xian Lu, Zhenhua Li, Gary R. Swenson, Steven Franke

Alan Z Liu

No abstract provided.


Judy Reservoir Monitoring Project 2011 Final Report, Robin A. Matthews, Joan Vandersypen Nov 2011

Judy Reservoir Monitoring Project 2011 Final Report, Robin A. Matthews, Joan Vandersypen

Judy Reservoir

The purpose of this study was to identify and count the phytoplankton and measure chlorophyll, total nitrogen, and total phosphorus levels in water samples collected from Judy Reservoir. Water quality and algal data have been collected on a weekly basis since October 2006; annual reports have been sent to the Skagit Public Utility District No. 1 in 2007, 2008, and 2010 (January and December).


Lake Samish Water Monitoring Project 2011b Final Report, Robin A. Matthews, Joan Vandersypen Nov 2011

Lake Samish Water Monitoring Project 2011b Final Report, Robin A. Matthews, Joan Vandersypen

Lake Samish

Lake Samish is a valuable aquatic resource, providing public access for boating, fishing, swimming, picnicking, and other water and lakeshore activities. Residents around the lake enjoy outstanding views of both the lake and its surrounding watershed, and the lake serves as a water supply for many of the lakeshore residents. Lake Samish is located in the Washington State Department of Ecology’s Water Resource Inventory Area #3 (WRIA 3), and discharges into Friday Creek, a salmon spawning tributary of the Samish River.

Lake Samish experiences periodic algal blooms, including blooms of potentially toxic cyanobacteria. The major goal of the monitoring project …


The Limits To Prediction In Ecological Systems, Brian Beckage, Louis J. Gross, Stuart Kauffman Nov 2011

The Limits To Prediction In Ecological Systems, Brian Beckage, Louis J. Gross, Stuart Kauffman

College of Agriculture and Life Sciences Faculty Publications

Predicting the future trajectories of ecological systems is increasingly important as the magnitude of anthropogenic perturbation of the earth systems grows.We distinguish between two types of predictability: the intrinsic or theoretical predictability of a system and the realized predictability that is achieved using available models and parameterizations. We contend that there are strong limits on the intrinsic predictability of ecological systems that arise from inherent characteristics of biological systems. While the realized predictability of ecological systems can be limited by process and parameter misspecification or uncertainty, we argue that the intrinsic predictability of ecological systems is widely and strongly limited …


Consistency In Statistical Moments As A Test For Bubble Cloud Clustering, Thomas C. Weber, Anthony P. Lyons, David L. Bradley Nov 2011

Consistency In Statistical Moments As A Test For Bubble Cloud Clustering, Thomas C. Weber, Anthony P. Lyons, David L. Bradley

Center for Coastal and Ocean Mapping

Frequency dependent measurements of attenuation and/or sound speed through clouds of gas bubbles in liquids are often inverted to find the bubble size distribution and the void fraction of gas. The inversions are often done using an effective medium theory as a forward model under the assumption that the bubble positions are Poisson distributed (i.e., statistically independent). Under circumstances in which single scattering does not adequately describe the pressure field, the assumption of independence in position can yield large errors when clustering is present, leading to errors in the inverted bubble size distribution. It is difficult, however, to determine the …


2011 Aquatic Weed Surveys In Timothy Lake, Lake Harriet And North Fork Reservoir : Final Report, Mark D. Sytsma, Vanessa Howard Morgan Nov 2011

2011 Aquatic Weed Surveys In Timothy Lake, Lake Harriet And North Fork Reservoir : Final Report, Mark D. Sytsma, Vanessa Howard Morgan

Center for Lakes and Reservoirs Publications and Presentations

Portland General Electric (PGE) was issued a new license by the Federal Energy Regulatory Commission (FERC) for the continued operation and maintenance of the Clackamas River Hydroelectric Project No. 2195 (Project) on December 21, 2010. This Project is located on both the lower 16 miles of Oak Grove Fork of the Clackamas River (Oak Grove Fork) and the mainstem of the Clackamas River in Clackamas County, Oregon. The effects of relicensing this Project were addressed in the Final Environmental Impact Statement (FEIS) completed in December 2006 and included the issue of invasive aquatic weed species. The term “aquatic weed” is …


Climate Change In The Piscataqua/Great Bay Region: Past, Present, And Future, Cameron P. Wake, Elizabeth Burakowski, Eric Kelsey, Katharine Hayhoe, Anne Stoner, Chris Watson, Ellen Douglas Nov 2011

Climate Change In The Piscataqua/Great Bay Region: Past, Present, And Future, Cameron P. Wake, Elizabeth Burakowski, Eric Kelsey, Katharine Hayhoe, Anne Stoner, Chris Watson, Ellen Douglas

The Sustainability Institute Publications

Earth ’s climate changes. It always has and always will. However, an extensive body of scientific evidence indicates that human activities are now a significant force driving change in the Earth’s climate system. This report describes how the climate of the Piscataqua/Great Bay region of coastal New Hampshire in the United States has changed over the past century and how the future climate of the region will be affected by human activities that are warming the planet.

Overall, the region has been getting warmer and wetter over the last century, and the rate of change has increased over the last …


Sustainability And Climate Models For The Intermountain West: An Annotated Bibliography, Marianne A. Buehler, William E. Brown Jr. Nov 2011

Sustainability And Climate Models For The Intermountain West: An Annotated Bibliography, Marianne A. Buehler, William E. Brown Jr.

Brookings Mountain West Publications

This resource on climate models and sustainability in the Intermountain West, a region that includes the states of Arizona, Colorado, Idaho, Nevada, New Mexico, and Utah, is a collaborative effort between the UNLV Libraries (http://library.unlv.edu/) and Brookings Mountain West (http://brookingsmtnwest.unlv.edu/).

The selected citations include academic, government, and non-profit information that highlight ongoing research on climate models and sustainability efforts in the region. The websites, government studies, independent reports, scholarly articles, and media reports reflect the diversity and complexity of climate change and sustainability issues in a region that contains widely varying ecosystems. The Intermountain West, with its deserts, basins, mountains, …


Field Ecology Patterns Of High Latitude Coral Communities, Kristi A. Foster Nov 2011

Field Ecology Patterns Of High Latitude Coral Communities, Kristi A. Foster

HCNSO Student Theses and Dissertations

Some climate models predict that, within the next 30-50 years, sea surface temperatures (SSTs) will frequently exceed the current thermal tolerance of corals (Fitt et al. 2001; Hughes et al. 2003; Hoegh-Guldberg et al. 2007). A potential consequence is that mass coral bleaching may take place (i) during warm El Niño-Southern Oscillation (ENSO) events which are predicted to occur in some regions more frequently than the current 3-7 year periodicity (Hoegh-Guldberg 1999; Sheppard 2003) or (ii) perhaps as often as annually or biannually if corals and their symbionts are unable to acclimate to the higher SSTs (Donner et al. 2005, …


Analysis Of Solar Lyman-Alpha Backscatter Radiation In The Heliosphere, Brian Fayock Oct 2011

Analysis Of Solar Lyman-Alpha Backscatter Radiation In The Heliosphere, Brian Fayock

Von Braun Symposium Student Posters

No abstract provided.


Comparing Ingenio Santa Rosa Precipitation Data To Trmm And Hydroestimator Data For El Nino And Normal Years In Panama, Tiffany Keeton Oct 2011

Comparing Ingenio Santa Rosa Precipitation Data To Trmm And Hydroestimator Data For El Nino And Normal Years In Panama, Tiffany Keeton

Von Braun Symposium Student Posters

No abstract provided.


Geospatially Detecting Saccharum Spontaneum: An Invasion Of The Panama Canal Watershed, Casey L. Calamaio Oct 2011

Geospatially Detecting Saccharum Spontaneum: An Invasion Of The Panama Canal Watershed, Casey L. Calamaio

Von Braun Symposium Student Posters

No abstract provided.


Investigation Of Turbulence Transport In The Heliosphere, Lauren Kahre Oct 2011

Investigation Of Turbulence Transport In The Heliosphere, Lauren Kahre

Von Braun Symposium Student Posters

No abstract provided.


Environmental Prediction In Canadian Cities, James Voogt Oct 2011

Environmental Prediction In Canadian Cities, James Voogt

Geography & Environment Presentations

No abstract provided.


Effects Of Climate Change On Spring Ecosystem Hydroecology As A Guide To Developing Alternative Water Policies, Scott Mensing, Saxon E. Sharpe, Scott Bassett, Don Sada, Jim Thomas Oct 2011

Effects Of Climate Change On Spring Ecosystem Hydroecology As A Guide To Developing Alternative Water Policies, Scott Mensing, Saxon E. Sharpe, Scott Bassett, Don Sada, Jim Thomas

Climate Change Seminar Series (NNE)

Hydroecology: the interface of ecological systems and water which combines the scientific disciplines of hydrology and ecology

Goal: evaluate the hydrologic and climate history using pollen, loss on ignition, total inorganic carbon, and invertebrates from spring sediments in Spring Valley, Eastern Nevada and Snake Valley, Western Utah


Another Dimension From Lidar – Obtaining Foliage Density From Full Waveform Data, Thomas Adams, Peter Beets, Christopher Parrish Oct 2011

Another Dimension From Lidar – Obtaining Foliage Density From Full Waveform Data, Thomas Adams, Peter Beets, Christopher Parrish

Center for Coastal and Ocean Mapping

LiDAR tells the user where surfaces are, not what they are. In this study we investigate the potential for waveform LiDAR to provide more information on the nature of the returns over forestry. Waveform LiDAR was acquired for ten Pinus radiata plots in a New Zealand plantation, along with comprehensive leaf area sampling in 2m vertical bands. The decay rate of each waveform peak was shown to be a useful tool for estimating foliage density, and has potential for identifying regions containing ground and understorey. Leaf Area Density (LAD) is an expression of foliage density per unit height, and a …


Heating Up The Forest: Open-Top Chamber Warming Manipulation Of Arthropod Communities At Harvard And Duke Forests, Shannon L. Pelini, Francis P. Bowles, Aaron M. Ellison, Nicholas J. Gotelli, Nathan J. Sanders, Robert R. Dunn Oct 2011

Heating Up The Forest: Open-Top Chamber Warming Manipulation Of Arthropod Communities At Harvard And Duke Forests, Shannon L. Pelini, Francis P. Bowles, Aaron M. Ellison, Nicholas J. Gotelli, Nathan J. Sanders, Robert R. Dunn

College of Arts and Sciences Faculty Publications

1.Recent observations indicate that climatic change is altering biodiversity, and models suggest that the consequences of climate change will differ across latitude. However, long-term experimental field manipulations that directly test the predictions about organisms' responses to climate change across latitude are lacking. Such experiments could provide a more mechanistic understanding of the consequences of climate change on ecological communities and subsequent changes in ecosystem processes, facilitating better predictions of the effects of future climate change. 2.This field experiment uses octagonal, 5-m-diameter (c.22m 3) open-top chambers to simulate warming at northern (Harvard Forest, Massachusetts) and southern (Duke Forest, North Carolina) hardwood …


Circulation, Vol. 17, No. 1, Center For Coastal Physical Oceanography, Old Dominion University, Chester E. Grosch Oct 2011

Circulation, Vol. 17, No. 1, Center For Coastal Physical Oceanography, Old Dominion University, Chester E. Grosch

CCPO Circulation

Fall 2011 issue of CCPO Circulation featuring article "Langmuir Circulations" by Dr. Chester E. Grosch