Oceanography and Atmospheric Sciences and Meteorology Commons^™

Future Research Vessels, Larry P. Atkinson

CCPO Publications

The academic research vessel fleet in the United States is embarking on a great experiment. By 2004 we will know if SWATH vessels such as the Mlo Moana and the possible built Woods Hole Oceanographic Institution coastal SWATH have such great advantages that all future vessels will be of SWATH design. Or, we will find that the two hull forms have distinct niches and the fleet will evolve with a strategic mix. Regardless of the Mure hull form research vessels will grow in size to accommodate advanced technology and the people to run and maintain it. The research vessel will …

Application Of Tree-Structured Regression For Regional Precipitation Prediction Using General Circulation Model Output, Xiangshang Li, David J. Sailor

Mechanical and Materials Engineering Faculty Publications and Presentations

This study presents a tree-structured regression (TSR) method to relate daily precipitation with a variety of free-atmosphere variables. Historical data were used to identify distinct weather patterns associated with differing types of precipitation events. Models were developed using 67% of the data for training and the remaining data for model validation. Seasonal models were built for each of 2 US sites: San Francisco, California, and San Antonio, Texas. The average correlation between observed and simulated daily precipitation data series is 0.75 for the training set and 0.68 for the validation set. Relative humidity was found to be the dominant variable …

Advanced Atmospheric Water Vapor Dial Detection System, Tamer Refaat

Electrical & Computer Engineering Theses & Dissertations

Measurement of atmospheric water vapor is very important for understanding the Earth's climate and water cycle. The remote sensing Differential Absorption Lidar (DIAL) technique is a powerful method to perform such measurement from aircraft and space. This thesis describes a new advanced detection system, which incorporates major improvements regarding sensitivity and size. These improvements include a low noise advanced avalanche photodiode detector, a custom analog circuit, a 14-bit digitizer, a microcontroller for on board averaging and finally a fast computer interface.

This thesis describes the design and validation of this new water vapor DIAL detection system which was integrated onto …

Data Warehouse Techniques To Support Global On-Demand Weather Forecast Metrics, Meriellen C. Joga

Theses and Dissertations

Air Force pilots and other operators make crucial mission planning decisions based on weather forecasts; therefore, the ability to forecast the weather accurately is a critical issue to Air Force Weather (AFW) and its customers. The goal of this research is to provide Air Force Weather with a methodology to automate statistical data analysis for the purpose of providing on-demand metrics. A data warehousing methodology is developed and applied to the weather metrics problem in order to present an option that will facilitate on-demand metrics. On-line analytical processing (OLAP) and data mining solutions are also discussed.

An Intelligent User Interface To Support Air Force Weather Product Generation And Automated Metrics, Darryl N. Leon

Theses and Dissertations

Air Force pilots require dependable weather reports so they may avoid unsafe flying conditions. In order to better gauge the accuracy of its weather products, Air Force Weather has established the requirement for an Air Force-wide automated weather metrics program. Under the guidelines for this program, forecasts will automatically be compared to observed weather to determine their accuracy. Statistics will be collected in the hopes of determining forecast error trends that can be corrected through education and training. In order for the statistical data produced by such a program to draw reliable conclusions about forecast accuracy, however, the correct format …

Crop Updates 2000 Cereals - Part 3, Roslyn J. Jettner, Blakely Paynter, Glenn Macdonald, Pierre Fievez, Ian Foster, David Tennant, Wal Anderson, James Ridsdill-Smith, Celia Pavri, Ross Chapman, Senthold Asseng, Steve Carr, Brad Nutt, Lindrea Latham, Roger Jones, Anyou Liu, Clinton K. Revell, David Ferris, Roy Latta, Lisa-Jane Blacklow, Chris Matthews, Ted Woodburn, Paul Yeoh, Ian Rose, Anita Lyons, Simon Cook, Matthew L. Adams, Robert J. Corner

Crop Updates

This session covers eighteen papers from different authors:

BARLEY AND OAT AGRONOMY

1. Unicorn barley must meet malting specifications to be a viable option, Roslyn Jettnerand Blakely Paynter, Agriculture Western Australia

2. Optimum oat seed rates, Glenn McDonald, Agriculture Western Australia

3. Production and Quality of export Oaten Hay (1998 and 1989), Pierre Fievez, Pierre Fievez and Associates

FROST

4. Climatology of Frost in Southern Western Australia, Ian Foster, Agriculture Western Australia

5. Flowering calculator, David Tennant, Agriculture Western Australia

6. Some options for managing the risk of frost damage, Wal Anderson, Agriculture Western Australia

PASTURE

7. …

Soapbox: The Academic Research Fleet: An Exciting Time For Renewal, Larry Atkinson

CCPO Publications

(First Paragraph) Academic research ships in the United States are the envy of many scientists around the world. A great strength of our system is the diversity of ships and operators: users have a choice, the system can change. A weakness of the system is that very diversity: sometimes it is hard for us to act together. Nevertheless, we now must act together. The vitality of the academic fleet in the coming decades is at stake. The reason is simply because many of our ships, especially in the intermediate size range, will soon reach the end of their useful life.

Crop Updates 1999 - Cereals, Len W. Broadbridge, Doug Abrecht, D. Bakker, Greg Hamilton, Cliff Spann, Doug Rowe, Peter Fisher, Jennifer Bignell, Matthew Braimbridge, Bill Bowden, Ross Brennan, Reg Lunt, Senthold Asseng, Cherie Rowles, Simon Bedbrook, Chris Gazey, Mike Bolland, Garren Knell, Lyn Abbott, Zed Rengel, Wayne Pluske, Erin Cahill, Bill Crabtree, Matthew Evans, Tim Nielsen, Jat Bhathal, Rob Loughman, D. Rasmussen, Roger A C Jones, Sean Kelly, Ian Riley, Sharyn Tayor, Vivien Vanstone, Dominie Wright, Debbie Thackray, Simon Mckirdy, George Yan, Robin Wilson, Iain Barclay, Robin Mclean, Dean A. Diepeveen, Bill Lambe, Wal Anderson, Brenda Shackley, Mechelle Owen, Peter Burgess, Ben Curtis, Mohammed A. Hamza, Jamie Henderson, Frank Boetel, Alfredo Impiglia, Frances Hoyle, Darshan Sharma, Pierre Fievez, Blakely Paynter, Glenn Macdonald, Kevin Young, Andrew Blake, Keith Devenish, P J. Dolling, Roy Latta, Lisa-Jane Blacklow, Chris Matthews, Angelo Loi, Brad Nutt, Rochelle Mcrobb, David Webb, Andrew Mcrobb, Clinton K. Revell, James Ridsdill-Smith, Celia Pavri, David Tennant, Darryl Mclements, Ross Thompson, Mike Ewing, Tim Woodburn, Paul Yeoh, James Fisher, Art Diggle, Mark Whitten, Andrew Rate, Paul Carlile, Ed Blanchard, Bevan Buirchell, Lorraine Osborne, Tress Walmsley, Terry Piper, Cameron Weeks, Michael Dodd, Amanda Falconer, Caroline Peek, Glenn Adam, Camray Gethin, Richard Guinness, Daniel Fels, Andrew Rintoul, Mal Lamond, Roger Tapp, Craig White

Crop Updates

This article covers sixty papers

FOREWORD

ACKNOWLEDGMENTS

PLENARY PAPERS

1. Western Australia’s climate: trends and opportunities, Len W. Broadbridge, Director, Bureau of Meterorology

2. Managing seasonal variations in agriculture, Dr Doug Abrecht, Director, Dryland Research Institute, Merredin

CROP ESTABLISHMENT

3. Soil management to prevent waterlogging on duplex soils in the Great Southern, D. Bakker, Greg Hamilton, Cliff Spann and Doug Rowe, Agriculture Western Australia

4. The influence of no-till and press wheels on crop production for heavy soils, Peter Fisher, Jennifer Bignell, Matthew Braimbridge, Greg Hamilton, Agriculture

Western Australia

NUTRITION

5. Fertiliser nitrogen, applied late, needs …

Robust Course-Boundary Extraction Algorithms For Autonomous Vehicles, Chris Roman, Charles Reinholtz

Graduate School of Oceanography Faculty Publications

Practical autonomous robotic vehicles require dependable methods for accurately identifying course or roadway boundaries. The authors have developed a method to reliably extract the boundary line using simple dynamic thresholding, noise filtering, and blob removal. This article describes their efforts to apply this procedure in developing an autonomous vehicle.

Inversion And Analysis Of Remotely Sensed Atmospheric Water Vapor Measurements At 940nm, Jack Cutler Larsen

Mechanical & Aerospace Engineering Theses & Dissertations

The understanding and acceptance of remotely sensed atmospheric data depends strongly on the steps taken to characterize experiment error and validate observations through comparisons to other independent measurements. A formal error analysis of the Stratospheric Aerosol and Gas Experiment II (SAGE II) water vapor operational inversion algorithm is performed and compared to previous results. Random measurement errors were characterized by segmented least-squares profile fitting of the slant path absorption which found the error to be uncorrelated in the stratosphere with estimated variances significantly smaller than expected from 18-30 km. Estimates of null space error were developed from radiosonde hygrometers in …

Atmospheric Turbulence Scintillation Effects On Wavefront Tilt Estimation, James A. Louthain

Theses and Dissertations

A new atmospheric turbulence screen generator is developed for use in performance calculations of adaptive optics systems valid over a wide range of atmospheric turbulence parameters. The screen generator accounts for diffraction effects caused by weak turbulence and incorporates the phase, amplitude, and cross statistics of the perturbed optical field. The wavefront's phase and amplitude perturbations are taken from the correlation functions developed by Lee and Harp and the cross correlation of the phase and amplitude derived in this thesis. The screen generator uses a modal representation to perform a Fourier series expansion of the wavefront phase and amplitude over …

The Influence Of The Wastewater Drainage From The Las Vegas Valley On The Limnology Of Boulder Basin, Lake Mead, Nevada-Arizona, James F. Labounty, Michael J. Horn, Bureau Of Reclamation

Publications (WR)

Lake Mead, Colorado River, Arizona-Nevada, is one of the most heavily used reservoirs in the western United States, providing abundant recreational opportunities as well as downstream domestic and agricultural water for over 22 million users. Based on average nutrient levels and productivity, Lake Mead is classified as mildly mesotrophic. The interflow of the Colorado River dominates the limnology of much of the 106 km-long reservoir, and may still be identified at Hoover Dam under certain conditions. The lower basin of Lake Mead ending at Hoover Dam is known as Boulder Basin and is near the Las Vegas metropolitan area. Las …

Analysis Of Multimode Low-Probability-Of-Intercept (Lpi) Communications With Atmospheric Effects, Ala Ghordlo

Theses and Dissertations

This research expanded Low Probability of Intercept (LPI) communications analysis in two areas. First, multimode communication was included to account for ground to ground and air to ground links in addition to the standard air to air links traditionally used in LPI analysis. The propagation equations for the three modes of interest were derived and included in LPI analytic models in the form of a mode quality factor to account for multimode LPI scenarios. This new quality factor was used in studying several communication and interception link combinations. Variations due to differences between the communication and interception modes were presented …

Performance Analysis Of A Hartman Wavefront Sensor Used For Sensing Atmospheric Turbulence Statistics, Toby D. Reeves

Theses and Dissertations

Atmospheric turbulence parameters, such as Fried's coherence diameter, the outer scale of turbulence, and the turbulence power law, are related to the wavefront slope structure function (SSF). The SSF is defined as the second moment of the wavefront slope difference as a function of both time and position. Knowledge of the SSF allows turbulence parameters to be estimated. Hartmann wavefront sensor (H-WFS) slope measurements composed of both signal and noise, allow the SSF to be estimated by computing a mean square difference of H-WFS slope measurements. The quality of the SSF estimate is quantified by the signal-to-noise ratio (SNR) of …

Investigation Of Radio Wave Propagation In The Martian Ionosphere Utilizing Hf Sounding Techniques, Robert J. Yowell

Theses and Dissertations

This thesis presents a preliminary design of an ionospheric sounder to be carried aboard one or more of NASA's Mars Surveyor landers. Past Russian and American probes have indicated the existence of an ionosphere, but none of these missions remotely sensed this atmospheric layer from the surface. The rationale for utilizing a surface-based Martian ionospheric sounder is discussed. Based on NASA's choice of launch vehicle and power source, a low-weight, low-powered Chirp sounder using a horizontally-polarized dipole antenna is recommended for the sounder experiment. The sounder experiment should be conducted for at least one Martian year, in order to investigate …

A One-Dimensional Model For Storm Breaching Of Barrier Islands, Cheol Shik Shin

Civil & Environmental Engineering Theses & Dissertations

A set of numerical models is developed for simulating the four stages of barrier breaching characterized by one horizontal spatial dimension.

The SBEACH model is employed for the first stage of dune/beach erosion. The Lax-Wendroff two-step explicit scheme for Stage II is developed to simulate initiation of ocean flood propagation on initially dry barrier islands and the method of characteristics (MOC), is employed to compute additional boundary data. The development of the Preissmann implicit scheme for water motion and a forward time centered space explicit scheme for sediment motion in Stages III and IV provide a tool to study the …

Application Of Autoregressive Moving Average Linear Prediction Filters To The Characterization Of Solar Wind-Magnetosphere Coupling, Carter N. Borst

Theses and Dissertations

Linear prediction filtering techniques have been used in studying the coupling processes between the solar wind and magnetosphere. The magnetosphere is a complex, dynamic system with at least two independent coupling methods for energy input, driven and unloading. Linear models were built and tested on the Bargatze data set, consisting of over 70 days of geomagnetic indices and solar wind data ordered in 34 intervals of increasing geomagnetic activity. Linear filtering techniques employing single-and multiple-input, autoregressive models predicted values of the magnetic index AL from solar wind data. The impulse response curves of the AL-coupling function groups showed amplitude peaks …

The Role Of Frame Selection And Bispectrum Phase Reconstruction For Speckle Imaging Through Atmospheric Turbulence, Elizabeth A. Harpold

Theses and Dissertations

Frame selection using quality sharpness metrics have been shown in previous AFIT theses, to be effective in improving the final product of images obtained using adaptive optics. This thesis extends this idea to noncompensated speckle image data. Speckle image reconstruction is simulated with and without frame selection. Speckle images require the processing of hundreds of data frames. Frame selection is a method of reducing the amount of data required to reconstruct the image. A collection of short exposure image data frames of a single object are sorted based on sharpness metrics. Only the highest quality frames are retained and processed …

Analysis And Interpretation Of Ion Data Associated With Neutral Gas Releases In The Earth's Ionosphere, Timothy M. Shadid

Theses and Dissertations

Barium and strontium release experiments were conducted throughout 1991 from the Combined Release and Radiation Effects Satellite (CRRES) to study both natural and man-made disturbances in the earth's ionosphere. A mass spectrometer on the spacecraft counted the Ba and Sr ions as the cloud expanded. In this study, data from the G-1 (in sunlight) and G-11b (in darkness) releases were modeled to understand the source of the ion signals. The model reproduced the Ba⁺ sun data well assuming photoionization (τ = 28 s) was the primary ionization mechanism. However, it was not able to account for the remaining ion …

The Effect Of Meteorological Data Averaging Times On Plume Concentrations From Explosive Ordnance Disposal Open Burning Operations, Ida L. Widmann

Theses and Dissertations

Explosive Ordnance Disposal (EOD) Open Burning (OB) operations are performed to treat and dispose of unserviceable munitions in the Department of Defense (DOD) inventory. Air pollution modeling of OB operations is an Environmental Protection Agency requirement for permit issuance at OB sites. Specific OB regulation is still in its infancy; therefore, establishment of OB modeling techniques is still in the early stages. This thesis effort sought to develop a computer model, based upon the Gaussian Puff Equation. The model varies from standard plume modeling practices by not making the assumption that the wind direction, wind speed and turbulence are uniform …

Regional Variation In Temperature Humidity Index For Poultry Housing, Richard S. Gates, Hanzhong Zhang, Donald G. Colliver, Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

A building thermal model was used to compute hourly values of temperature humidity index (THI) for a broiler house with and without an evaporative misting system. Hourly summer time weather data for 238 U.S.A. locations covering 30 years were used to develop extreme occurrences of THI. Results were incorporated into a Geographical Information System (GIS) database to create isolines of THI and percentage of hours exceeding a heat stress threshold. Regional variations in misting as a suitable cooling technique are presented in terms of hours reduction in annual heat stress. The technique may be used for assisting in management decisions …

A Guide To Floodplain Cattle Fencing, Department Of Agriculture, Western Australia, Main Roads, Western Australia

Animal production and livestock published reports

A seminar and workshop was held at Fitzroy Crossing in October 1993 to address the consequences of flooding to landholders and communities.

Damage to flood plain fencing was identified as one of the major concerns to landholders.

An outcome from the workshop was the decision to draw on local knowledge and collate information on options for fence and floodgate designs.

This information was to be made available to land holders and other interested parties - hence this publication.

Bulletin 4279 - Streamlining - An Environmentally Sustainable Drainage Network For The Swan Coastal Plain (Peel-Harvey Catchment), Garry Heady, Neil Guise

Bulletins 4000 -

Community Catchment Centre Pinjarra

A network of over 1400 kilometres of drains and modified natural waterways constructed by the Public Works Department criss-crosses the Peel-Harvey catchment. There are also over 3300 kilometres of minor drains and natural waterways in this same region.

The expansion of agriculture relied on this extensive drainage network, which was designed to ensure rapid drainage of the region. Unfortunately there was little regard to future environmental consequences.

Along with drainage water, these same drains now carry high loads of silt and nutrients. Many of the drains are also degraded and require expensive maintenance annually.

Identification Of Tire Leachate Toxicants And A Risk Assessment Of Water Quality Effects Using Tire Reefs In Canals, S. M. Nelson, G. Mueller, D. C. Hemphill, U.S. Bureau Of Reclamation

Publications (WR)

Cover is an important component of aquatic habitat and fisheries management. Fisheries biologists often try to improve habitats through the addition of natural and artificial material to improve cover diversity and complexity. Habitat-improvement programs range from submerging used Christmas trees to more complex programs using sophisticated artificial habitat modules. Used automobile tires have been employed in the large scale construction of reefs and fish attractors in marine environments and to a lesser extent in freshwater and have been recognized as a durable, inexpensive and long-lasting material which benefits fishery communities.

Recent studies by the U.S. Bureau of Reclamation have quantified …

Shock Wave Interaction With L-Shaped Structures, Richard C. Miller

Theses and Dissertations

This study investigated the interaction of shock waves with L-shaped structures using the CTH hydrodynamics code developed by Sandia National Laboratories. Computer models of shock waves traveling through air were developed using techniques similar to shock tube experiments. Models of L-shaped buildings were used to determine overpressures achieved by the reflecting shock versus angle of incidence of the shock front. An L-shaped building model rotated 45 degrees to the planar shock front produced the highest reflected overpressure of 9.73 atmospheres in the corner joining the two wings, a value 9.5 times the incident overpressure of 1.02 atmospheres. The same L-shaped …

Including Maximum Sustained Wind Speed In A Time Series Model To Forecast Hurricane Movement, Timothy B. Mott

Theses and Dissertations

Techniques for applying time series fundamentals to forecasting hurricane movement are thoroughly examined in this research. The objectives are: (1) to modify Dr. Thomas Curry's threshold autoregressive time series model to improve its ability to forecast hurricane movement, (2) to forecast the maximum sustained wind speed for a hurricane, and (3) to identify if wind speed should be included as an explanatory variable to aid in forecasting hurricane movement. Eleven different models to predict the latitude, longitude and maximum sustained wind speed are compared and contrasted with Curry's bivariate time series model. The results showed the modifications allow significant forecasting …

Southern Nevada Effluent Wetlands: A Proposed Cooperative Venture Between The Bureau Of Reclamation & City Of Las Vegas, Bureau Of Reclamation

Publications (WR)

Throughout North America there is a growing interest in constructed wetlands, both as relatively inexpensive, low-maintenance systems for removing nutrients from wastewater, and as a means of using municipal wastewater to enhance wildlife habitat and create public use opportunities. Because wetlands appear to have good potential as a component in the overall management of scarce water resources, the Bureau of Reclamation (Reclamation) has undertaken several cooperative research and demonstration projects to evaluate their effectiveness in a variety of local environments. While a number of projects have demonstrated that wetlands can be beneficially employed to improve water quality, few such projects …

Removal Of Mercury From Waste Water: Large-Scale Performance Of An Ion Exchange Process, James A. Ritter, J. P. Bibler

Faculty Publications

Duolite™ GT-73 ion exchange resin routinely reduces the mercury content of a waste water stream to less than the permitted level of 10 ppb. Effluent concentrations from the ion exchange facility (IEF) are consistently between 1 to 5 ppb, even though the feed contains a varying concentration of mercury (0.2 to 70 ppm). Two operational problems have been encountered at that facility, however. Firstly, the stated capacity of the resin for mercury was not being achieved. The abnormally low capacity was traced to analytical laboratory waste which was intermittently treated by the resin. That waste contained hydrochloric acid, stannous chloride, …

Analytical Modeling And Simulation For Investigation Of A Digital Gas Filter Correlation Radiometer, Catherine P. Mcgowan

Electrical & Computer Engineering Theses & Dissertations

This thesis investigates a digital gas filter correlation radiometer called the Tropospheric Radiometer for Atmospheric Chemistry and Environmental Research (TRACER), which will be used to remotely measure carbon monoxide at three levels in the troposphere. The nadir-viewing radiometer measures the differential absorption of radiation through the atmosphere at 4.67@m and 2.33pm wavelengths. This thesis develops an analytical model of the TRACER measurement process to evaluate the effect of varying certain system parameters on the measurement. The independent sampling criterion and the response of linear systems to random signals are explained. A parametric simulation model is also developed to evaluate the …

Modifications To Mcnp, Version 3b: Incorporating A Variable Density Atmosphere. Addendum, David L. Monti, Kirk A. Mathews

AFIT Documents

MCNP version 3B was modified to incorporate a continuously variable density atmosphere. This was accomplished by representing the variation of air density as a function of altitude with a series of continuous piecewise exponential curves up to a maximum altitude of 1000 km. User-written subroutines and functions were written which incorporated these piecewise functions. These subroutines and functions were subsequently incorporated into a production version of MCNP. Several MCNP subroutines and files were modified in support of these modifications. This report discusses detailed information regarding the theoretical development of the variable density model, the user written subroutines and functions, the …