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Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

2012

Oceanography and Atmospheric Sciences and Meteorology

Embry-Riddle Aeronautical University

Articles 1 - 16 of 16

Full-Text Articles in Physical Sciences and Mathematics

Histological Changes In The Target Organs Of Channa Punctatus After Exposure To Anthraquinone Vat Dyes, Rajee Olaganathan, Jamila Patterson Dec 2012

Histological Changes In The Target Organs Of Channa Punctatus After Exposure To Anthraquinone Vat Dyes, Rajee Olaganathan, Jamila Patterson

Publications

The present study is an attempt on histopathology of gill, liver, kidney and intestine of Channa punctatus after exposure to sublethal concentrations of anthraquinone vat dyes viz., vat blue 4 and vat green 1. The dyes has been found to produce several damages in the vital organs of C. punctatus leading to various lesions like extensive lamellar hypertrophy with some proliferation at the base of secondary lamellae and hyperplasia of intercellular epithelial cells in the gill; fat accumulation, hepatic necrosis, aggregation of polymorphonuclear leucocytes, hepatocellular degeneration and aggregation of hepatocytes in liver; while in kidney it caused hyperplastic of the …

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Identification And Classification Of Stratospheric Sudden Warming Events, Thomas S. Ehrmann Dec 2012

Identification And Classification Of Stratospheric Sudden Warming Events, Thomas S. Ehrmann

Doctoral Dissertations and Master's Theses

Analysis of northern hemisphere stratospheric data from 1978-2011 is used to identify and classify Stratospheric Sudden Warming events. A total of 41 events are identified during this 33 year period, resulting in an average occurrence rate of 1.24 events/year. No significant variation in the rate is observed during the period analyzed. The average temperature increase during an SSW event is 12 K and the average duration is 32 days. Each identified event is classified as either a vortex displacement or split event and the ratio of displacement to split events is found to be 0.86.

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An Intense Traveling Airglow Front In The Upper Mesosphere–Lower Thermosphere With Characteristics Of A Bore Observed Over Alice Springs, Australia, During A Strong 2 Day Wave Episode, R. L. Walterscheid, J. H. Hecht, L. J. Galinas, Michael P. Hickey Ph.D., I. M. Reid Nov 2012

An Intense Traveling Airglow Front In The Upper Mesosphere–Lower Thermosphere With Characteristics Of A Bore Observed Over Alice Springs, Australia, During A Strong 2 Day Wave Episode, R. L. Walterscheid, J. H. Hecht, L. J. Galinas, Michael P. Hickey Ph.D., I. M. Reid

Publications

The Aerospace Corporation’s Nightglow Imager observed a large step function change in airglow in the form of a traveling front in the OH Meinel (OHM) and O2 atmospheric (O2A) airglow emissions over Alice Springs, Australia, on 2 February 2003. The front exhibited nearly a factor of 2 stepwise increase in the OHM brightness and a stepwise decrease in the O2A brightness. There was significant (~25 K) cooling behind the airglow fronts. The OHM airglow brightness behind the front was among the brightest for Alice Springs that we have measured in 7 years of observations. The event was associated with a …

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A Gap Analysis Of Meteorological Requirements For Commercial Space Operators, Nicholas Stapleton Nov 2012

A Gap Analysis Of Meteorological Requirements For Commercial Space Operators, Nicholas Stapleton

Doctoral Dissertations and Master's Theses

Commercial space companies will soon be the primary method of launching people and supplies into orbit. Among the critical aspects of space launches are the meteorological concerns. Laws and regulations pertaining to meteorological considerations have been created to ensure the safety of the space industry and those living around spaceports; but, are they adequate? Perhaps the commercial space industry can turn to the commercial aviation industry to help answer that question. Throughout its history, the aviation industry has dealt with lessons learned from mishaps due to failures in understanding the significance of weather impacts on operations. Using lessons from the …

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Sensitivity Of Limiting Hurricane Intensity To Ocean Warmth, James B. Elsner, Sarah Strazzo, Jill C. Trepanier, Thomas H. Jagger Sep 2012

Sensitivity Of Limiting Hurricane Intensity To Ocean Warmth, James B. Elsner, Sarah Strazzo, Jill C. Trepanier, Thomas H. Jagger

Publications

No abstract provided.

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General Aviation Weather Encounter Case Studies, John M. Lanicci, Massoud Bazargan, Daniel Halperin, Scott Shappell, Jaclyn Baron, Rebecca Iden, Carla Hackworth, Kali Holcomb Sep 2012

General Aviation Weather Encounter Case Studies, John M. Lanicci, Massoud Bazargan, Daniel Halperin, Scott Shappell, Jaclyn Baron, Rebecca Iden, Carla Hackworth, Kali Holcomb

School of Graduate Studies - Daytona Beach

This study presents a compilation of 24 cases involving general aviation (GA) pilots’ weather encounters over the continental U.S. The project team interviewed pilots who had experienced a weather encounter, and we examined their backgrounds, flight experience, and weather encounter details. Results from meteorological data analysis for each weather encounter were consistent with findings of larger GA weather accident studies in terms of the types of hazards encountered and flight phase during which the encounters occurred. Investigation of pilot weather products and the sources from which they were obtained revealed a lack of uniformity of pre-flight data sources and underutilization …

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Biodegradation Of Textile Dye Anthraquinone Vat Blue 4 By Pseudomonas Aeruginosa, Rajee Olaganathan, Jamila Patterson Aug 2012

Biodegradation Of Textile Dye Anthraquinone Vat Blue 4 By Pseudomonas Aeruginosa, Rajee Olaganathan, Jamila Patterson

Publications

Uncontaminated and Vat blue 4 contaminated soil were screened for heterotrophic bacterial population and the bacterial density were found to be 19.3 X 104 and 5.5 X 104 CFU/gm respectively. The bacterial genera of dye contaminated soil was dominated by Pseudomonas sp. (32.5 %) followed by Bacillus sp. (27.5 %), Aeromonas sp. (15.0 %), Micrococcus sp. (12.5 %) and Achromobacter sp. (12.5 %). The optimum inoculums load, pH and temperature were found to be 5%, 7 and 35oC respectively. The initial pH of the effluent prepared using Vat Blue 4 was 8.5. The free cells of P. aeruginosa reduced the …

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Ionospheric Signatures Of Tohoku-Oki Tsunami Of March 11, 2011: Model Comparisons Near The Epicenter, David A. Galvan, Attila Komjathy, Michael P. Hickey, Philip Stephens, Jonathan Snively, Y. Tony Song, Mark D. Butala, Anthony J. Mannucci Jul 2012

Ionospheric Signatures Of Tohoku-Oki Tsunami Of March 11, 2011: Model Comparisons Near The Epicenter, David A. Galvan, Attila Komjathy, Michael P. Hickey, Philip Stephens, Jonathan Snively, Y. Tony Song, Mark D. Butala, Anthony J. Mannucci

Publications

We observe ionospheric perturbations caused by the Tohoku earthquake and tsunami of March 11, 2011. Perturbations near the epicenter were found in measurements of ionospheric total electron content (TEC) from 1198 GPS receivers in the Japanese GEONET network. For the first time for this event, we compare these observations with the estimated magnitude and speed of a tsunami-driven atmospheric gravity wave, using an atmosphere-ionosphere-coupling model and a tsunami model of sea-surface height, respectively. Traveling ionospheric disturbances (TIDs) were observed moving away from the epicenter at approximate speeds of 3400 m/s, 1000 m/s and 200–300 m/s, consistent with Rayleigh waves, acoustic …

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Ionospheric Plasma Transport And Loss In Auroral Downward Current Regions, M. Zettergren, J. L. Semeter Jun 2012

Ionospheric Plasma Transport And Loss In Auroral Downward Current Regions, M. Zettergren, J. L. Semeter

Publications

A detailed study of the effects of auroral current systems on thermal ionospheric plasma transport and loss is conducted using a new ionospheric model. The mathematical formulation of the model is a variation on the 5‐moment approximation which describes the temporal evolution of density, drift, and temperature for five different ion species in two spatial dimensions. The fluid system is closed through a 2‐D electrostatic treatment of the auroral currents. This model is used to examine the interplay between ion heating, perpendicular transport, molecular ion generation, and type‐1 ion upflows in a self‐consistent way for the first time. Simulations confirm …

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Gravity Wave Propagation In A Diffusively Separated Gas: Effects On The Total Gas, Michael P. Hickey Ph.D., R. L. Walterscheid May 2012

Gravity Wave Propagation In A Diffusively Separated Gas: Effects On The Total Gas, Michael P. Hickey Ph.D., R. L. Walterscheid

Publications

We present a full-wave model that simulates acoustic-gravity wave propagation in a binary-gas mixture of atomic oxygen and molecular nitrogen, including molecular viscosity and thermal conductivity appropriately partitioned between the two gases. Compositional effects include the collisional transfer of heat and momentum by mutual diffusion between the two gases. An important result of compositional effects is that the velocity and temperature summed over species can be significantly different from the results of one-gas models with the same height dependent mean molecular weight (M(z)). We compare the results of our binary-gas model to two one-gas full-wave models: one where M is …

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Synoptic-Scale Analysis Of Freezing Rain Events In Montreal, Quebec, Canada, Gina M. Ressler, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum Apr 2012

Synoptic-Scale Analysis Of Freezing Rain Events In Montreal, Quebec, Canada, Gina M. Ressler, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum

Publications

Freezing rain is a major environmental hazard that is especially common along the St. Lawrence River valley (SLRV) in southern Quebec, Canada. For large cities such as Montreal, severe events can have a devastating effect on people, property, and commerce. In this study, a composite analysis of 46 long-duration events for the period 1979–2008 is presented to identify key synoptic-scale structures and precursors of Montreal freezing rain events. Based on the observed structures of the 500-hPa heights, these events are manually partitioned into three types—west, central, and east—depending on the location and tilt of the 500-hPa trough axis. West events …

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Synoptic-Scale Environments Conducive To Orographic Impacts On Cold-Season Surface Wind Regimes At Montreal, Quebec, Alissa Razy, Shawn M. Milrad, Eyad H, Atallah, John R. Gyakum Mar 2012

Synoptic-Scale Environments Conducive To Orographic Impacts On Cold-Season Surface Wind Regimes At Montreal, Quebec, Alissa Razy, Shawn M. Milrad, Eyad H, Atallah, John R. Gyakum

Publications

Orographic wind channeling, defined as dynamically and thermally induced processes that force wind to blow along the axis of a valley, is a common occurrence along the St. Lawrence River Valley (SLRV) in Quebec, Canada, and produces substantial observed weather impacts at stations along the valley, including Montreal (CYUL). Cold-season observed north-northeast (n = 55) and south-southeast (n = 16) surface wind events at CYUL are identified from 1979 to 2002. The authors partition the north-northeast wind events into four groups using manual synoptic typing. Types A and D (“inland cyclone” and “northwestern cyclone”) are associated with strong lower-tropospheric geostrophic …

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Gravity-Wave-Induced Variations In Exothermic Heating In The Low-Latitude, Equinox Mesophere And Lower Thermosphere Region, Michael P. Hickey Ph.D., Tai-Yin Huang Feb 2012

Gravity-Wave-Induced Variations In Exothermic Heating In The Low-Latitude, Equinox Mesophere And Lower Thermosphere Region, Michael P. Hickey Ph.D., Tai-Yin Huang

Publications

We investigate gravity-wave-induced variations in exothermic heating in the OH nightglow region at a latitude of 18° in the Northern and Southern Hemispheres during March. An OH nightglow chemistry model with gravity wavefields from a spectral full-wave model is used for the investigation. Our simulation results show that the wave packet induces a large secular increase in the number densities of the minor species involved in the OH chemistry, a 50% increase in O3, 42% in O, and 29% in OH (v= 8), and the ultimate driver for these increases is the wave-driven downward transport of O. We find that …

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Revisiting 3d Stereo Satellite Image Displays, Frederick R. Mosher Jan 2012

Revisiting 3d Stereo Satellite Image Displays, Frederick R. Mosher

Applied Aviation Sciences - Daytona Beach

Over 30 years ago, there were a number of development efforts to display 3D stereo satellite images and associated weather. Dr. Fritz Hasler showed how the GOES-east and west satellites could be remapped to generate true stereo pairs for obtaining cloud heights and he also showed how artificial stereo images could be generated using derived IR cloud heights to generate parallax shifts for the visible or infrared images. While there was a flurry of interest in the 1980s, the techniques had largely fallen from routine usage until recently. However, technology advances in both satellites and display technology has allowed for …

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Detecting Ionospheric Tec Perturbations Caused By Natural Hazards Using A Global Network Of Gps Receivers: The Tohoku Case Study, A. Komjathy, D. A. Galvan, P. Stephens, M. D. Butala, V. Akopian, B. Wilson, O. Verkhoglyadova, A. J. Mannucci, M. Hickey Jan 2012

Detecting Ionospheric Tec Perturbations Caused By Natural Hazards Using A Global Network Of Gps Receivers: The Tohoku Case Study, A. Komjathy, D. A. Galvan, P. Stephens, M. D. Butala, V. Akopian, B. Wilson, O. Verkhoglyadova, A. J. Mannucci, M. Hickey

Physical Sciences - Daytona Beach

Recent advances in GPS data processing have demonstrated that ground-based GPS receivers are capable of detecting ionospheric TEC perturbations caused by surface-generated Rayleigh, acoustic and gravity waves. There have been a number of publications discussing TEC perturbations immediately following the M 9.0 Tohoku earthquake in Japan on March 11, 2011. Most investigators have focused on the ionospheric responses up to a few hours following the earthquake and tsunami. In our research, in addition to March 11, 2011 we investigate global ionospheric TEC perturbations a day before and after the event. We also compare indices of geomagnetic activity on all three …

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Disparities In Weather Education Across Professional Flight Baccalaureate Degree Programs, Thomas A. Guinn, Krista M. Rader, Thomas A. Guinn Jan 2012

Disparities In Weather Education Across Professional Flight Baccalaureate Degree Programs, Thomas A. Guinn, Krista M. Rader, Thomas A. Guinn

Publications

The required meteorology coursework for 22 accredited professional flight baccalaureate degree programs was examined and compared. Significant differences were noted in both the number of required meteorology courses as well as the number of required meteorology credit hours. While all programs required at least one three-credit meteorology course, not all programs required an aviation-specific meteorology course. In addition to the required number of meteorology courses and credit hours, topics within the aviation-specific meteorology courses were also examined. The study showed the topics of “flight hazards” and “aviation weather reports and charts” were identified most frequently in course descriptions, followed third …

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