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Statistical Characteristics Of Polar Mesospheric Gravity Waves Observed Over Alaska, Michael Negale, Kim Nielsen, Michael J. Taylor, Dominique Pautet, Margit Dyrland 2013 Utah State University

Statistical Characteristics Of Polar Mesospheric Gravity Waves Observed Over Alaska, Michael Negale, Kim Nielsen, Michael J. Taylor, Dominique Pautet, Margit Dyrland

Physics Student Research

Momentum deposition by short-period (<1 hr) gravity waves is known to play a major role in the global circulation in the mesosphere and lower thermosphere (MLT) region ~80-100 km (e.g. Fritts and Alexander, 2003). Observations of these waves over the Arctic Region are few and their impact on the Arctic MLT region is of high interest, but has yet to be determined. The Mesospheric Airglow Imaging and Dynamics (MAID) project was initiated in January 2011 to investigate short-period gravity wave dynamics over central Alaska. MAID is a collaborative project between Utah Valley University (UVU) (Principle Investigator Kim Nielsen), Utah State University (USU), and the University of Alaska, Fairbanks (UAF).

The main goals of this project are to:
-Establish a long-term climatology of short-period gravity waves observed in the Arctic MLT region.
-Determine dominant source regions and potential sources of the observed waves.
-Investigate the impact of large-scale waves (tides and planetary waves) on the short-period wave field.
-Perform quantitative comparison between Arctic and Antarctic winter-time dynamics.

In this poster, we focus on quantifying the climatology of short-period gravity waves during two winter seasons (2011-2012) over central Alaska.


A Crowdsourced Hail Dataset: Potential, Biases, And Inaccuracies, Joseph Robert Pehoski 2013 University of Wisconsin-Milwaukee

A Crowdsourced Hail Dataset: Potential, Biases, And Inaccuracies, Joseph Robert Pehoski

Theses and Dissertations

Hail is a substantial severe weather hazard in the USA, with significant damage to property and

crops occurring annually. Traditional methods of forecasting hail size have limited accuracy, and despite

improvements in remote sensing of precipitation, the fall characteristics of hail make quantification of

hail imprecise. Research into hail is ongoing, but traditional hail datasets have known biases and low

spatiotemporal resolution. The increased usage of smartphones creates the opportunity to use a

crowdsourced dataset provided by the Precipitation Identification Near the Ground (PING) program, a

program developed by the National Severe Storms Laboratory. PING data is compared to approximate …


Species Composition And Reproductive Strategies Of Commensal Synalpheus Shrimp (Decapoda:Alpheidae) Occupying The Sponges Spheciospongia Vesparium And Spongia Sp. Of The Florida Reef Tract, Brittnee Nicole Barris 2013 Nova Southeastern University

Species Composition And Reproductive Strategies Of Commensal Synalpheus Shrimp (Decapoda:Alpheidae) Occupying The Sponges Spheciospongia Vesparium And Spongia Sp. Of The Florida Reef Tract, Brittnee Nicole Barris

HCNSO Student Theses and Dissertations

Synalpheus shrimp species of the gambarelloides group are the only marine organisms displaying the highest level of social functioning, eusociality. Their social hierarchies are equally complex compared to the reproductive abnormalities that have been recently discovered. For instance, snapping shrimp of the genus Synalpheus were thought to be gonochoric, i.e. developing as independent sexes, until scanning electron microscopy studies revealed intersexed gonopores in several species. This project analyzed both the species composition, and accompanying reproductive structures, of Synalpheus spp. (Caridea: Alpheidae) comprised of densely aggregating communal and pair-living colonies in the Florida Keys, Florida.

Colonies of pair-living and communal Synalpheus …


Educating The Masses: Human Attitudes Affecting Reef Health, Ashley Wiehl 2013 Nova Southeastern University

Educating The Masses: Human Attitudes Affecting Reef Health, Ashley Wiehl

HCNSO Student Theses and Dissertations

About two thirds of the world’s population lives within 60 km of a coastline, however many members of the public do not recognize the importance of the nearby coral reef ecosystems. Although reef degradation is currently occurring at alarming rates, there is hope for the future of coral reef health. It is proven that humans have a large effect on the current health of coral reefs. This thesis aims to determine how marine scientists and educators can best influence the general public to affect behaviors to improve reef health. To do this involves taking analyzing the many effects of human …


Mass Bays Resource Inventory: Summary And Findings From The Review Of Plans And Assessments, Urban Harbors Institute, University of Massachusetts Boston 2013 University of Massachusetts Boston

Mass Bays Resource Inventory: Summary And Findings From The Review Of Plans And Assessments, Urban Harbors Institute, University Of Massachusetts Boston

Urban Harbors Institute Publications

The Massachusetts Bays Program (MBP) contracted with the Urban Harbors Institute (UHI) of the University of Massachusetts Boston to conduct a review of papers, presentations, reports, and other relevant material produced from 1996 (the last CCMP) to present, that might inform the MBP’s update of their Comprehensive Conservation and Management Plan (CCMP). The review focused on five topics identified as priority topics by the MBP: water quality, invasive species, climate change/vulnerability, continuity of estuarine habitat, and estuarine habitat protection in the geographic region of the Mass Bays Program, particularly the 47 nearshore estuaries and embayments identified in the 2012 MBP …


Looking Forward Transdisciplinary Modeling, Environmental Forecasting, And Management, D. B. Haidvogel, E. Turner, E. N. Curchitser, E. E. Hofmann 2013 Old Dominion University

Looking Forward Transdisciplinary Modeling, Environmental Forecasting, And Management, D. B. Haidvogel, E. Turner, E. N. Curchitser, E. E. Hofmann

CCPO Publications

No abstract provided.


Reservoir Management Techniques To Enhance Biological Productivity And Protect Water Quality, Ben Alan Thompson 2013 University of Arkansas, Fayetteville

Reservoir Management Techniques To Enhance Biological Productivity And Protect Water Quality, Ben Alan Thompson

Graduate Theses and Dissertations

Three reservoirs of similar size, watershed land use, and qualitative characteristics in northwest Arkansas, USA were selected to compare the effects of chemical fertilization and pulsed artificial-upwelling on whole-lake productivity, specifically primary production and phytoplankton biomass. Numerous water quality parameters were quantified over a two year period (2011-13) with the goal of understanding how each management technique would stimulate productivity. This experiment was the first step towards a larger goal to ultimately enhance sport fish production. The first year of monitoring occurred in 2011 and served as a control year for the three lakes. Treatments were initiated in two of …


Assessing Growth Response To Climate Controls In A Great Basin Artemisia Tridentata Plant Community, Lorenzo F. Apodaca 2013 University of Nevada, Las Vegas

Assessing Growth Response To Climate Controls In A Great Basin Artemisia Tridentata Plant Community, Lorenzo F. Apodaca

UNLV Theses, Dissertations, Professional Papers, and Capstones

An assessment of the growth response of key vegetative species to climatic variability is vital to identifying possible local impacts on ecosystems faced with imminent climate change. With current climate projections in Nevada predicting a shift to an even more arid climate with greater year-to-year variability, the imperative exists to identify the effects of specific climatic controls on plant growth and to research methods to assess large-scale vegetative changes, especially in more remote areas where readily available data sets may be lacking. This study utilized annual growth ring indices constructed from big sagebrush (Artemisia tridentatassp.tridentata) stems collected in Spring Valley, …


Statistical Characteristics Of Polar Mesospheric Gravity Waves Observed Over Alaska, Michael Negale, Kim Nielsen, Mike J. Taylor, Dominique Pautet, Margit Dyrland 2013 Utah State University

Statistical Characteristics Of Polar Mesospheric Gravity Waves Observed Over Alaska, Michael Negale, Kim Nielsen, Mike J. Taylor, Dominique Pautet, Margit Dyrland

Michael Negale

Short-period (<1 hr) gravity wave observations over the Arctic region are few and their impact on the Arctic mesosphere lower thermosphere (MLT) region via momentum deposition is of high interest, but has yet to be determined. The Mesospheric Airglow Imaging and Dynamics (MAID) project was initiated in January 2011 to investigate the presence and dynamics of these waves over the interior of Alaska. Observations were made from the Davis Building at Poker Flat Research Range (PFRR) (65N) using an all-sky imager. This site provides an exceptional opportunity to establish a long-term climatology of short-period gravity waves in the Arctic. Here, we present summary measurements of prominent gravity waves focusing on their winter-time spatial and temporal characteristics. Measurements were made over two consecutive winters in 2011 and 2012 yielding 117 quasi-monochromatic wave events obtained from sequential OH (715-930 nm) images. Their characteristics are compared with recent gravity wave observations at Resolute Bay, Canada (75N), ALOMAR Station, Norway (69N), Svalbard (78N) in the Arctic, and with Rothera Station (76S) in Antarctic. The distributions of the wave parameters measured at PFRR were found to be similar to those of the other high-latitude sites, except for the direction of propagation. The wave headings observed at PFRR exhibited dominant preference for motion towards the east, while the other high-latitude observations reported westward motion. To investigate the preferred wave directionality, we look at the effects of critical level filtering using zonal and meridional winds obtained from NASA’s Modern-Era Retrospective Analysis for Research and Applications (MERRA) and the Horizontal Wind Model 2007 (HWM07).


Auroral Ion Upflows: Sources, High Altitude Dynamics, And Neutral Wind Effects, Meghan R. Burleigh 2013 Embry-Riddle Aeronautical University - Daytona Beach

Auroral Ion Upflows: Sources, High Altitude Dynamics, And Neutral Wind Effects, Meghan R. Burleigh

Doctoral Dissertations and Master's Theses

Large upwellings of thermal plasma are commonly observed in the high-latitude, topside ionosphere. These auroral ion upflows have a range of potential sources including frictional heating, electron precipitation, neutral winds, and higher-altitude density cavities. The unique signatures and detailed evolution of these upflows are examined through the use of Incoherent Scatter Radar data and a sophisticated ionospheric fluid model.

A survey of solar cycle 23 shows that at Sondrestrom upflows occur most often in the cusp region and midnight auroral zone. Simplified force balance analysis and steady state velocity calculations are applied to a few select events to elucidate the …


Cnh: Collaborative Research: Direct And Indirect Coupling Of Fisheries Through Economic, Regulatory, Environmental, And Ecological Linkages, Andrew J. Pershing, Yong Chen, Jeffrey Runge 2013 Principal Investigator; University of Maine, Orono

Cnh: Collaborative Research: Direct And Indirect Coupling Of Fisheries Through Economic, Regulatory, Environmental, And Ecological Linkages, Andrew J. Pershing, Yong Chen, Jeffrey Runge

University of Maine Office of Research Administration: Grant Reports

The productivity and resilience of fisheries are subject to a multitude of dynamic and interrelated influences that arise from complex coupling of fish populations with the natural and human systems of which they are a part. With few exceptions, fisheries currently are managed independently, ignoring important natural and human linkages among them. The biological productivity, sustainability, and consequently human benefits of complex fishery systems may be substantially increased if these linkages are better understood and if this understanding is applied to management. The American lobster (Homarus americanus), Atlantic herring (Clupea harengus) and Northeast multispecies groundfish fisheries in the Gulf of …


Wave Heating And Jeans Escape In The Martian Upper Atmosphere, R. L. Walterscheid, Michael P. Hickey Ph.D., G. Schubert 2013 The Aerospace Corporation

Wave Heating And Jeans Escape In The Martian Upper Atmosphere, R. L. Walterscheid, Michael P. Hickey Ph.D., G. Schubert

Publications

Gusty flow over rough terrain is likely to be a significant source of fast gravity waves and acoustic waves in the atmosphere of Mars, as it is in Earth’s atmosphere. Accordingly, we have used a numerical model to study the dissipation in the thermosphere and exosphere of Mars of upward-propagating fast gravity waves and acoustic waves. Model simulations are performed for a range of wave periods and horizontal wavelengths. Wave amplitudes are constrained by the Mars Global Surveyor and Mars Odyssey aerobraking data, and gravity wave phase velocities are limited by occultation data. Dissipating gravity waves heat some regions of …


Collaborative Research: Subglacial Water Intrusion In Greenland, Gordon K. Oswald 2013 The University of Maine

Collaborative Research: Subglacial Water Intrusion In Greenland, Gordon K. Oswald

University of Maine Office of Research Administration: Grant Reports

The project's goals are:

  • To analyse radio echo sounding data acquired over the Greenland Ice Sheet by the University of Kansas / CReSIS team with the objective of discriminating between frozen and thawed conditions at the bed of the ice sheet.
  • To provide maps of the bed state, with the aim of making them available via the National Snow and Ice Data Centre.
  • To support ice sheet modelling activities by providing information on the bed state, thus related to the temperature at the bed and the rheological conditions at the bed.
  • To make available to educational establishments information on the …


Determining The Extent And Characterizing Coral Reef Habitats Of The Northern Latitudes Of The Florida Reef Tract (Martin County), Brian K. Walker, David S. Gilliam 2013 Nova Southeastern University

Determining The Extent And Characterizing Coral Reef Habitats Of The Northern Latitudes Of The Florida Reef Tract (Martin County), Brian K. Walker, David S. Gilliam

Marine & Environmental Sciences Faculty Articles

Climate change has recently been implicated in poleward shifts of many tropical species including corals; thus attention focused on higher-latitude coral communities is warranted to investigate possible range expansions and ecosystem shifts due to global warming. As the northern extension of the Florida Reef Tract (FRT), the third-largest barrier reef ecosystem in the world, southeast Florida (25–27° N latitude) is a prime region to study such effects. Most of the shallow-water FRT benthic habitats have been mapped, however minimal data and limited knowledge exist about the coral reef communities of its northernmost reaches off Martin County. First benthic habitat mapping …


Introduction To Special Section On The U.S. Ioos Coastal And Ocean Modeling Testbed, Richard A. Luettich Jr, L. Donelson Wright, Richard Signell, Carl T. Friedrichs, Marjorie A.M. Friedrichs, John Harding, Katja Fennel, Eoin Howlett, Sara Graves, Elizabeth Smith, Gary Crane, Rebecca Baltes 2013 Virginia Institute of Marine Science

Introduction To Special Section On The U.S. Ioos Coastal And Ocean Modeling Testbed, Richard A. Luettich Jr, L. Donelson Wright, Richard Signell, Carl T. Friedrichs, Marjorie A.M. Friedrichs, John Harding, Katja Fennel, Eoin Howlett, Sara Graves, Elizabeth Smith, Gary Crane, Rebecca Baltes

VIMS Articles

Strong and strategic collaborations among experts from academia, federal operational centers, and industry have been forged to create a U.S. IOOS Coastal and Ocean Modeling Testbed (COMT). The COMT mission is to accelerate the transition of scientific and technical advances from the coastal and ocean modeling research community to improved operational ocean products and services. This is achieved via the evaluation of existing technology or the development of new technology depending on the status of technology within the research community. The initial phase of the COMT has addressed three coastal and ocean prediction challenges of great societal importance: estuarine hypoxia …


Kinetic Fractionation Of Gases By Deep Air Convection In Polar Firn, K. Kawamura, J. P. Severinghaus, M. R. Albert, Z. R. Courville 2013 National Institute for Polar Research

Kinetic Fractionation Of Gases By Deep Air Convection In Polar Firn, K. Kawamura, J. P. Severinghaus, M. R. Albert, Z. R. Courville

Dartmouth Scholarship

A previously unrecognized type of gas fractiona- tion occurs in firn air columns subjected to intense convec- tion. It is a form of kinetic fractionation that depends on the fact that different gases have different molecular diffusivi- ties. Convective mixing continually disturbs diffusive equi- librium, and gases diffuse back toward diffusive equilibrium under the influence of gravity and thermal gradients. In near- surface firn where convection and diffusion compete as gas transport mechanisms, slow-diffusing gases such as krypton (Kr) and xenon (Xe) are more heavily impacted by convec- tion than fast diffusing gases such as nitrogen (N2) and ar- gon …


Stable Isotope And Modelling Evidence For Co2 As A Driver Of Glacial-Interglacial Vegetation Shifts In Southern Africa, F. J. Bragg, I. C. Prentice, S. P. Harrison, G. Eglinton, P. N. Foster 2013 University of Bristol

Stable Isotope And Modelling Evidence For Co2 As A Driver Of Glacial-Interglacial Vegetation Shifts In Southern Africa, F. J. Bragg, I. C. Prentice, S. P. Harrison, G. Eglinton, P. N. Foster

Dartmouth Scholarship

Atmospheric CO2 concentration is hypothesized to influence vegetation distribution via tree-grass competition, with higher CO2 concentrations favouring trees. The stable carbon isotope (delta C-13) signature of vegetation is influenced by the relative importance of C-4 plants (including most tropical grasses) and C-3 plants (including nearly all trees), and the degree of stomatal closure - a response to aridity in C-3 plants. Compound-specific delta C-13 analyses of leaf-wax biomarkers in sediment cores of an offshore South Atlantic transect are used here as a record of vegetation changes in subequatorial Africa. These data suggest a large increase in C3 relative to C4 …


Mapping Of The Quasi-Periodic Oscillations At The Flank Magnetopause Into The Ionosphere, Emily R. Dougal 2013 Embry-Riddle Aeronautical University - Daytona Beach

Mapping Of The Quasi-Periodic Oscillations At The Flank Magnetopause Into The Ionosphere, Emily R. Dougal

Doctoral Dissertations and Master's Theses

We have estimated the ionospheric location, area, and travel time of quasi-periodic oscillations originating from the magnetospheric flanks. This was accomplished by utilizing global and local MHD models and Tsyganenko semi-empirical magnetic field model on multiple published and four new cases believed to be caused by the Kelvin-Helmholtz Instability. Finally, we used auroral, magnetometer, and radar instruments to observe the ionospheric signatures. The ionospheric magnetic latitude determined using global MHD and Tsyganenko models ranged from 58.3-80.2 degrees in the northern hemisphere and -59.6 degrees to -83.4 degrees in the southern hemisphere. The ionospheric magnetic local time ranged between 5.0-13.8 hours …


Collaborative Research: Centers For Ocean Sciences Education Excellence - National Network Partnerships, Annette V. deCharon 2013 Principal Investigator; University of Maine, Orono

Collaborative Research: Centers For Ocean Sciences Education Excellence - National Network Partnerships, Annette V. Decharon

University of Maine Office of Research Administration: Grant Reports

This proposal will be awarded using funds made available by the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).

This award provides funds to support the Centers for Ocean Sciences Education Excellence (COSEE) Central Coordinating Office (CCO) in a set of projects that will focus on identifying best practices in ocean science education and develop internal and external Network partnerships. Specifically, this award provides funds for the development of an online COSEE Community Center to network teachers, ocean researchers and the public.

The COSEE program, now in its seventh year, has a mission to bridge the gap between …


Coupling Self-Organizing Maps With A Naïve Bayesian Classifier: Stream Classification Studies Using Multiple Assessment Data, Nikolaos Fytilis, Donna M. Rizzo 2013 University of Vermont

Coupling Self-Organizing Maps With A Naïve Bayesian Classifier: Stream Classification Studies Using Multiple Assessment Data, Nikolaos Fytilis, Donna M. Rizzo

College of Engineering and Mathematical Sciences Faculty Publications

Organizing or clustering data into natural groups is one of the most fundamental aspects of understanding and mining information. The recent explosion in sensor networks and data storage associated with hydrological monitoring has created a huge potential for automating data analysis and classification of large, high-dimensional data sets. In this work, we develop a new classification tool that couples a Naïve Bayesian classifier with a neural network clustering algorithm (i.e., Kohonen Self-Organizing Map (SOM)). The combined Bayesian-SOM algorithm reduces classification error by leveraging the Bayesian's ability to accommodate parameter uncertainty with the SOM's ability to reduce high-dimensional data to lower …


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