Oceanography and Atmospheric Sciences and Meteorology Commons^™

Colder By The Lake? The Lake Effect On Static Air Temperatures In Duluth, Minnesota 1961-1990, Graham A. Tobin, Gordon L. Levine, Jacqueline H. Alexander

Journal of the Minnesota Academy of Science

To test the impact of Lake Superior on local climates, daily temperature data were collected from two weather stations in Duluth, Minnesota for the period 1961 through 1990. The broad goal of the research was to ascertain to what extent climate conditions differed between lakeside and inland locations. Temperature data were standardized to local lake-level to control for altitudinal differences between weather stations. These data were then analyzed at two temporal scales, annual and seasonal, with the focus on mean high and mean low temperatures. Results indicated that the moderating effect of the lake indeed was apparent especially in raising …

Johnston, Jesse Walter, Sr., 1880-1972 (Sc 1337), Manuscripts & Folklife Archives

Manuscript Collection Finding Aids

Finding aid and typescript (Click on "Additional Files" below) for Manuscripts Small Collection 1337. Journal kept by Jesse Walter Johnston, Sr., Sebree, Webster County, Kentucky, concerning the destructive 1937 flood and data about Johnston. He was minister of the First Baptist Church, Sebree from 1929 to 1944.

Africa: An Integrated Curriculum Unit, Grades 2-4, Institute For The Development Of Gifted Education, Ricks Center For Gifted Children, University Of Denver

Ricks Curriculum Units Series

An integrated curriculum is an instructional approach that connects the disciplines to an underlying theme or topic. Immersing students in an integrated-thematic unit provides the backdrop for experiences to occur across the disciplines. Shaping coursework around integrated themes is especially appropriate for gifted students, however using an integrated-thematic curriculum is appropriate for all learners as it develops students' abilities to make connections, to solve problems by looking at multiple perspectives, and to integrate information from different fields of experience. An integrated-thematic curriculum permits students to be active participants in their own learning as they design their own explorations and take …

Frontogenesis In The North Pacific Oceanic Frontal Zones--A Numerical Simulation, Michael S. Dinniman, Michele M. Rienecker

CCPO Publications

A primitive equation model [Geophysical Fluid Dynamics Laboratory's (GFDL's) MOM 2] with one degree horizontal resolution is used to simulate the seasonal cycle of frontogenesis in the subarctic frontal zone (SAFZ) and the subtropical frontal zone (STFZ) of the North Pacific Ocean. The SAFZ in the model contains deep (greater than 500 m in some places) regions with seasonally varying high gradients in temperature and salinity. The gradients generally weaken toward the east. The STFZ consists of a relatively shallow (less than 200 m in most places) region of high gradient in temperature that disappears in the summer/fall. The high …

Summary Of The Noaa/Utah Atmospheric Modification Program: 1990-1996, United States Department Of The Interior, Bureau Of Reclamation

Meterology

This final report summarizes physical investigations into the artificial nucleation ("seeding") of winter mountain clouds in central Utah during 1990-96. Program goals were to evaluate the effectiveness of the Utah operational cloud seeding program and to recommend improvements. Field programs employed a wide variety of instrumentation systems. Sophisticated numerical modeling was used in conjunction with the observational programs. Amounts and distributions of SLW (supercooled liquid water) cloud were investigated, as was transport and dispersion of ground-released seeding agents and tracer gases. Several experiments directly monitored ice crystals and snowfall rates resulting from either silver iodide (Agl) or liquid propane seeding. …

Analytic Forms Of Bidirectional Reflectance Functions For Application To Earth Radiation Budget Studies, N. Manalo-Smith, G. L. Smith, S. N. Tiwari, W. F. Staylor

Mechanical & Aerospace Engineering Faculty Publications

Analytic expressions for the bidirectional reflectance functions are formulated and fit to the Earth Radiation Budget Experiment (ERBE) operational models, which were developed using Nimbus 7 ERB data. The analytic bidirectional reflectance distribution functions (BRDFs) are based on theoretical considerations and are functions of viewing geometry and scene type. The models consist of a Rayleigh scattering term and a term for scattering due to clouds and surface. The darkness of the ocean permits the empirical determination of the Rayleigh component of scattering from the atmosphere. The models have the advantage that they are smooth in terms of view and solar …

Ua12/2/1 Special Storm Coverage, Wku Student Affairs

WKU Administration Documents

Special hail storm coverage edition of the College Heights Herald:

• Batcheldor, Matt. Campus Damage Exceeds $4 Million; No One Hurt – Hail, Flooding
• Moore, Leigh. Downing University Center Roof Destroyed; Food Services Continue – Hail, Dining Services
• Batcheldor, Matt. Weather or Not . . . Hail, Flooding

Ua52/1 Hail Storm Memories, Wku Archives

WKU Administration Documents

Memories of WKU faculty, staff, alumni and the general public regarding the 1988 hail storm solicited by WKU Archives.

Studies Of Warm-Core Rings Using A Particle-In-Cell Method, John James Holdzkom Ii

OES Theses and Dissertations

A particle-in-cell (PIC) model is developed and applied to problems involving the evolution of warm-core rings. Such models are a hybrid of conventional Eulerian and Lagrangian models. They are ideally suited for problems in which a lower layer outcrops to the surface, such as at the boundary of a ring.

The model is developed in three implementations. First, for purposes of model validation, a reduced gravity model is described. The PIC model reproduces the essential characteristics of analytical solutions to the reduced gravity equations and integral invariants are conserved to a high degree. Next, a 1.5-layer model is developed and …

An Analytical Study Of Ozone Feedbacks On Kelvin And Rossby–Gravity Waves: Effects On The Qbo, Eugene Cordero, Terrence R. Nathan, Robert S. Echols

Faculty Publications, Meteorology and Climate Science

An equatorial beta-plane model of the middle atmosphere is used to analytically examine the effects of radiative cooling and ozone heating on the spatial and temporal evolution of the quasi-biennial oscillation (QBO). Under the assumption that the diabatic heating is weak and the background fields of wind, temperature, and ozone are slowly varying, a perturbation analysis yields expressions describing the vertical spatial modulation of Kelvin and Rossby–gravity waves in the presence of ozone. These expressions show that wave-induced changes in the diabatic heating arising from the advection of basic-state ozone reduce the local radiative damping rate by up to 15% …

Azimuth And Range Optimization Of The Velocity Azimuth Display (Vad) Algorithm In The Wsr-88d, David L. Craft

Theses and Dissertations

The Velocity Azimuth Display (VAD) algorithm occasionally produces inaccurate wind estimates for the VAD Wind Profile (VWP) product of the Weather Surveillance Radar 1988 Doppler (WSR-88D) System. Weather forecasters have observed differences between the radar's wind profiles and wind profiles produced by rawinsondes and vertical wind profilers, when radiation and subsidence inversions in the atmosphere caused the radar beam to super refract. This thesis sought to improve the operational use of the VWP product for the WSR-88D near Denver, CO, by finding the optimal VAD algorithm Azimuth and Range parameter settings to overcome data contamination by hills located at the …

Calibrated Probabilistic Quantitative Precipitation Forecasts Based On The Mrf Ensemble, Frederick Anthony Eckel

Theses and Dissertations

Probabilistic quantitative precipitation forecasts (PQPF) based on the medium range forecast (MRF) ensemble are currently in operational use below their full potential quality (i.e., accuracy and reliability). This unfulfilled potential is due to the MRF ensemble being adversely affected by systematic errors which arise from an imperfect model and less than ideal ensemble initial perturbations. This thesis sought to construct a calibration to account for these systematic errors and thus produce higher quality PQPF. Systematic errors were explored with the use of the verification rank histogram, which tracks the performance of the ensemble. The information in these histograms was then …

Evaluation Of Satellite Microwave Derived Surface Temperature Algorithms For The Period August 1996 To February 1997, Charles H. Harris

Theses and Dissertations

The Air Force Weather Agency (AFWA) has two operational algorithms that derive surface temperatures from microwave observations taken by the Special Sensor Microwave Imager (SSM/I) which rides aboard space platforms of the Defense Meteorological Satellite Program (DMSP). The algorithm called Temperature from Satellite Microwave Imager (TS) is used to analyze global cloud coverage. The second algorithm is fittingly called Calibration and Validation (CV), as it was the algorithm used to calibrate and validate the first SSM/I in 1987. Multiple linear regression defined the algorithms from empirically gathered brightness temperatures and simultaneous surface temperatures. The key questions were how much data …

Nowcasting Thunderstorms At Cape Canaveral, Florida, Using An Improved Neumann-Pfeffer Thunderstorm Index, Cindy L. Howell

Theses and Dissertations

The Neumann-Pfeffer Thunderstorm Index (NPTI) is used daily by the 45th Weather Squadron during the convective season to estimate the probability of afternoon thunderstorms. The current I , developed by Charles J. Neumann in the 1960s, i based on only 13 years of data taken over 30 years ago. The index was in desperate need of an upgrade. Following the multiple regression techniques outlined by Neumann, this thesis examines whether or not including additional data would improve the performance of the NPTI. After performing the multiple regressions and retuning the regression coefficients, both NPTs were validated using a 2-year independent …

A Comparison Of Advect Cloud Model And Fifth-Generation Mesoscale Model Total Fractional Cloud Forecasts, Brian D. Pukall

Theses and Dissertations

Total fractional cloudiness (FC) forecasts from the advect cloud (ADVCLD) model and total FC forecasts diagnosed from the relative humidity and total cloud condensate (snow, ice, rain water, and cloud water) fields from the fifth generation mesoscale model (MM5) were statistically and subjectively compared to determine which model produced the better total FC forecasts from August through November 1997 for a forecast window centered on Bosnia. The real time nephanalysis (RTNFPH) model was used to represent the true state of the atmosphere. ADVCLD and MM5 forecasts were also compared against a persistence forecast to provide a minimal skill baseline. The …

Analyzing Horizontal Distances Between Wsr-88d Thunderstorm Centroids And Cloud-To-Ground Lightning Strikes, Steve L. Renner

Theses and Dissertations

On April 29, 1996, lightning struck the airfield at Hurlburt Field, FL, killing one Airmen and injuring ten others. This cloud to ground lightning strike hit eight minutes after a lightning advisory was canceled. At the time of the strike, thunderstorms were observed 7 to 10 miles north and south of the airfield. The incident raised questions about Air Force Weather Agency's lightning criteria. Soon after the incident, a Lightning Safety Review Panel was assembled to determine the adequacy of lightning advisories. One of the questions posed to the panel was could an incident like Hurlburt happen again? The review …

Improving Cape Canaveral's Day-2 Thunderstorm Forecasting Using Meso-Eta Numerical Model Output, Christian S. Wohlwend

Theses and Dissertations

The 45th Weather Squadron (WS) is responsible for the protection of billions of dollars worth of Air Force and NASA equipment from weather hazards. They produce a seven day planning forecast as one tool to support the space launch community. Improving this forecast can potentially save millions of dollars of government funds. This research focuses on the feasibility of improving the day two thunderstorm forecast by applying Meso Eta numerical forecasts to the Neumann-Pfeffer Thunderstorm Index (NPTI). The NPTI is currently used by the 45th WS for same day thunderstorm probability forecasting utilizing the morning radiosonde as input. The perfect …

Forecasting Wet Microbursts Associated With Summertime Airmass Thunderstorms Over The Southeastern United States, James B. Mackey

Theses and Dissertations

Microbursts are intense downbursts from thunderstorms that affect an area less than 4 km and have a lifespan less than 10 minutes. Wet microbursts are associated with heavy precipitation and are common in the eastern and southeastern part of the country. The greatest threat from microbursts is to low flying aircraft, where the rapid fluctuations in horizontal and vertical airflow create tremendous shear zones. Microbursts have been determined to be the causal factor behind at least three major aircraft accidents resulting in numerous fatalities. Due to the short lifespan of microbursts, they often strike without warning and pose a serious …

A Validation Study Of The Air Force Weather Agency (Afwa) Jetrax Contrail Forecast Algorithm, Jeffrey D. Shull

Theses and Dissertations

Accurate contrail forecasts allow pilots to avoid levels of the atmosphere which are conducive to contrail formation, reducing their likelihood of being visually detected by enemy forces. The primary objective of this thesis is to evaluate the performance of the JETRAX contrail forecast algorithm currently used by the Air Force Weather Agency to support military air operations. A total of 397 ground-based contrail observations were collected at Wright-Patterson Air Force Base on 27 different days. Observations were collected with the aid of air traffic control radar, which greatly facilitated the positive identification of overflying aircraft and provided necessary information such …

Data Assimilation Experiments In The Gulf Stream Region: How Useful Are Satellite-Derived Surface Data For Nowcasting The Subsurface Fields?, Tal Ezer, George L. Mellor

CCPO Publications

Satellite-derived surface data have become an important source of information for studies of the Gulf Stream system. The question of just how useful these datasets are for nowcasting the subsurface thermal fields, however, remains to be fully explored. Three types of surface data-sea surface temperature (SST), sea surface height (SSH), and Gulf Stream position (GSP)-are used here in a series of data assimilation experiments to test their usefulness when assimilated into a realistic primitive equation model. The U.S. Navy's analysis fields from the Optimal Thermal Interpolation System are used to simulate the surface data and to evaluate nowcast errors. Correlation …

An Analysis Of Tropical Transport: Influence Of The Quasi-Biennial Oscillation, Eugene C. Cordero, S. Randolph Kawa, Mark R. Schoeberl

Faculty Publications, Meteorology and Climate Science

An analysis of over 4 years of Upper Atmosphere Research Satellite (UARS) measurements of CH₄, HF, O₃, and zonal wind are used to study the influence of the quasi-biennial oscillation (QBO) on constituent transport in the tropics. At the equator, spectral analysis of the Halogen Occultation Experiment (HALOE) and Microwave Limb Sounder (MLS) observations reveals QBO signals in constituent and temperature fields at altitudes between 20 and 45 km. Between these altitudes, the location of the maximum QBO amplitude roughly corresponds with the location of the largest vertical gradient in the constituent field. Thus, at 40 …

Validation Of The Air Force Global Weather Center Relocatable Window Model Total Cloud Forecast, Edward C. Harris

Theses and Dissertations

Air Force Global Weather Center's (AFGWC) Relocatable Window Model (RWM) total cloud forecasts were validated using data for selected days in May, June, and July, 1996. Forecasts were generated twice daily (00 UTC and 12 UTC) to determine the RWM's ability to accurately forecast total cloud cover during the late spring and early summer. The RWM forecasts were post-processed using the Slingo cloud forecast algorithm and compared against AFGWC's operational real time nephanalysis (RTNEPH) cloud analysis model. As a minimal-skill baseline comparison to the RWM's total cloud forecast, the RTNEPH initial analysis hour was persisted and evaluated against the same …

Quantification Of Weather Effects On Imaging Laser Radar, Clifton D. Stargardt

Theses and Dissertations

The Air Force is investigating the use of imaging laser radar systems as autonomous guidance systems on future precision guided munitions. The Air Force's Wright Laboratory is currently testing a 1.06 micron wavelength laser radar (ladar) at Eglin Air Force Base. Since laser radiation can be susceptible to propagation problems through weather, quantitative understanding of these effects is important to the development of this weapon system. Ladar image degradation, in the form of target dropouts and false returns, was evaluated in various weather conditions. Statistical analysis of the images presented expected degrees of degradation according to visibility and rain fall …

Moisture Sensitivity Of Contrail Forecast Algorithms, Allen C. Rabayda

Theses and Dissertations

This thesis looked at using new relative humidity (RH) climatologies to improve the Air Force Global Weather Center's (AFGWC) contrail forecasts. To study the effect of the new RH climatolgies, the currently used empirical relative humidity (RH) profile is replaced with a more accurate climatological one, the Stratospheric And Gaseous Experiment II (SAGE II). The study begins by examining accuracy and bias of forecast contrail bases generated by the empirical and SAGE II RH profiles on 42 days. Both sets of forecast bases are shown to be statistically similar with a series of hypothesis tests. Additional RH profiles, from 0% …

A Validation Study Of The Ssm/I Temperature Algorithm And Comparison With The Cal/Val Land Surface Temperatures, Ronald L. Comoglio

Theses and Dissertations

The USAF operational cloud model, the Real-Time Nephanalysis (RTNEPH), requires infrared and visual scene scans as well as input from the Special Sensor Microwave Imager (SSM/I), featured on the Defense Meteorological Satellite Program (DMSP) polar orbiters. Additionally, SSM/I provides input to the Air Force Global Weather Center (AFGWC) surface temperature model (SFCTMP). The global surface temperatures are required for identifying which pixel of a scene is cloud and which is ground and as a first guess input to initialize NWP models. The SSM/I provides brightness temperatures sampled at four discrete: frequencies and dual polarizations to produce surface temperatures. Two algorithms …

An Examination Of The Hanson Contrail Forecast Algorithm Under Low Relative Humidity Conditions, Robert P. Asbury Iii

Theses and Dissertations

Accurate forecasts of contrail occurrence are essential to military aircrews. Although classical forecast methods have been reasonably successful predicting contrails, there is need for improvement at low ambient relative humidity. This thesis examines the performance of the Hanson method, which was developed to provide better contrail forecasts under drier atmospheric conditions. As a secondary objective, the forecast methods of Schumann and Hanson are compared to the algorithm currently in use by the Air Force Global Weather Central. Data used to validate the algorithms were collected at Wright-Patterson AFB, OH and Edwards AFB, CA. Theoretical contrail forecasts were made for each …

Development And Implementation Of An Isentropic Potential Vorticity Algorithm For Use At Air Force Global Weather Center, Jay B. Desjardins Jr.

Theses and Dissertations

This thesis presents and validates methods for calculating isentropic potential vorticity (IPV) and applies these methods in software programs planned for implementation at the Air Force Global Weather Center (AFGWC). The IPV programs will provide Air Force Weather forecasters additional tools to diagnose atmospheric kinematics and understand atmospheric dynamics. A FORTRAN program is recommended using mandatory-level isobaric data projected to be available on AFGWC computer systems, specifically, from the Navy Operational Global Atmosphere Prediction System and Medium Range Forecast models. Program development and analysis consists of three main steps: (1) data retrieval; (2) IPV calculations; and, (3) interpolation to an …

Adaption Of The Air Weather Service Fog Model To Forecast Radiation Fog Events In The Southeast United States, Andrew C. Goodnite

Theses and Dissertations

This research examined the performance of the Air Weather Service (AWS) Fog Model and the potential for using it in the Southeast United States for predicting fog. This task was accomplished in four separate steps. First, a correlation study was performed by comparing different weather elements in observations that met radiational cooling conditions to the observed visibility. This correlation study showed that the 22 UTC dewpoint depression was correlated (0.60) with early morning fog and no other weather elements that are commonly observed had significant correlation with early morning fog. Second, a verification study was conducted on the Saint Louis …

Optimization Of The Velocity Azimuth Display (Vad) Algorithm's Adaptable Parameters In The Wsr-88d System, Donald R. Farris

Theses and Dissertations

Meteorologists have encountered problems with the Velocity Azimuth Display (VAD) algorithm in the Weather Surveillance Radar - 1988 Doppler (WSR-88D) System. Under certain meteorological conditions, forecasters have observed differences between the radar's wind profiles and wind profiles from rawinsonde upper-air soundings, or wind profilers. One of the main causes of this problem is inversions in the atmosphere which cause the radar beam to subrefract or superefract, causing the VAD winds to be inaccurately reported at a particular height. This thesis used the WSR-88D Algorithm Testing and Display System (WATADS) to compare VAD winds from recorded Level 2 NEXRAD data at …

Measuring The Momentum Of Throughfall Drops And Raindrops, Paul Kimble

Masters Theses & Specialist Projects

The methods previously used to determine the momentum and kinetic energy of throughfall drops in the field do not account for the drop's shape at impact or for the variations of the drop's velocity caused by chaotic air currents. The drop's shape at impact is critical because it influences the drop's measurable momentum, kinetic energy, impact force, and the amount of soil that can be displaced by the falling water drop. Since the momentum and kinetic energy of raindrops and throughfall drops are used as indices of soil particle displacement the most accurate momentum and kinetic energydata would be required …