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A comparison of atmospheric transport considerations in eastern and western oil shale operations

Description: Atmospheric transport represents one of the critically important pathways for the distribution of pollutants from any oil shale operation. Our experience in studying eastern and western shale resources and operation suggest many common features regarding the atmospheric domain, but also many significant differences. Any issue of atmospheric transport and dispersion can be broken down into major elements: source factors which include the spatial and temporal distribution of pollutant sources as well as their chemical and physical characteristics, boundary conditions which include the character of the underlying surface as a lower boundary and the large scale meteorological circulations as an ''upper'' boundary; and meteorological structure is the resulting wind, temperature, moisture, and turbulence environment in the volume of air occupied by emitted material in an atmosphere subjected to the boundary conditions described above. For purposes of planning an industry, we want to be able to reliably model the atmospheric structure on a variety of time and space scales and the subsequent distribution of pollutants. This paper discusses differences in modeling concepts and results in the separate environments of eastern and western oil shale resources. 10 refs., 5 figs.
Date: January 1, 1987
Creator: Barr, S.
Partner: UNT Libraries Government Documents Department

Large scale meteorological influence during the Geysers 1979 field experiment

Description: A series of meteorological field measurements conducted during July 1979 near Cobb Mountain in Northern California reveals evidence of several scales of atmospheric circulation consistent with the climatic pattern of the area. The scales of influence are reflected in the structure of wind and temperature in vertically stratified layers at a given observation site. Large scale synoptic gradient flow dominates the wind field above about twice the height of the topographic ridge. Below that there is a mixture of effects with evidence of a diurnal sea breeze influence and a sublayer of katabatic winds. The July observations demonstrate that weak migratory circulations in the large scale synoptic meteorological pattern have a significant influence on the day-to-day gradient winds and must be accounted for in planning meteorological programs including tracer experiments.
Date: January 1, 1980
Creator: Barr, S.
Partner: UNT Libraries Government Documents Department

Roles of complex and simple terrain in the estimation of atmospheric diffusion

Description: The highly specialized yet integrated requirements for theory, numerical modeling, and field experiments have led to the organization of teams that incorporate different specialties around a shared objective. This paper attempts to establish a context for the dominant terrain effects including the role of vegetative cover. Some practical needs for a thorough understanding of terrain influence are explored, some of the phenomena that have been identified as complicating the transport and diffusion of pollutants are reviewed. A variety of methods that have been used to characterize the topography itself for atmospheric transport applications are reviewed.
Date: January 1, 1981
Creator: Barr, S.
Partner: UNT Libraries Government Documents Department

Comparison of lateral and vertical diffusion in several valleys

Description: The turbulent dispersion of tracers nocturnal in four valleys was examined. Two are reasonably large with greater than 600-m terrain relief and two are well-formed but are shallow and narrow. Both Anderson Creek, California and Parachute Creek, Colorado are large and deep enough to produce a systematic cool air drainage wind regime although the difference in valley shapes makes the structure of that wind field quite different. Parachute Creek is a deep linear valley in which a vigorous down-valley flow develops and exits at the mouth without significant obstruction. Anderson Creek is a three-dimensional bowl with a very flat outflow region from which the cool air backs up to form a quasi-stagnant pool 200 to 300 m deep. Inhomogeneous turbulence is a major factor in the transport history of tracers in Anderson Creek. In the slope-wind potion of the basin the plume growth is systematic and about 1.5 to 2 Pasquill-Gifford categories more vigorous than estimated by radiation and windspeed. The slower mean wind and greater meandering that the plume encounters in the cool air pool makes a distinct change in the tracer cloud behavior. Residence times are long and the apparent width of a time integrated plume is much greater than predicted by plume model considerations. The two small-scale terrain features, Corral Gulch and Los Alamos Canyon, tend to channel the wind generated locally on the next larger scale but produce only weak, shallow slope-wind characteristics themselves. The gross diffusion is more vigorous by about one Pasquill-Gifford category than indicated by the radiation- windspeed system and is consistent with measured sigma/sub A/ values. Both valleys tend to constrain the lateral spread of tracer. Vertical growth estimates suggest that plumes can grow above the height of the valley walls. It is reasonable to expect that material thus exhaled by a ...
Date: January 1, 1983
Creator: Barr, S.
Partner: UNT Libraries Government Documents Department

Division of Biological and Medical Research research summary 1984-1985

Description: The Division of Biological and Medical Research at Argonne National Laboratory conducts multidisciplinary research aimed at defining the biological and medical hazards to man from energy technologies and new energy options. These technically oriented studies have a strong base in fundamental research in a variety of scientific disciplines, including molecular and cellular biology, biophysics, genetics, radiobiology, pharmacology, biochemistry, chemistry, environmental toxicology, and epidemiology. This research summary is organized into six parts. The first five parts reflect the Divisional structure and contain the scientific program chapters, which summarize the activities of the individual groups during the calendar year 1984 and the first half of 1985. To provide better continuity and perspective, previous work is sometimes briefly described. Although the summaries are short, efforts have been made to indicate the range of research activities for each group.
Date: August 1, 1985
Creator: Barr, S.H. (ed.)
Partner: UNT Libraries Government Documents Department

Division of Biological and Medical Research annual research summary, 1983

Description: This research summary contains brief descriptions of research in the following areas: (1) mechanisms of hepatocarcinogenesis; (2) role of metals in cocarcinogenesis and the use of liposomes for metal mobilization; (3) control of mutagenesis and cell differentiation in cultured cells by tumor promoters; (4) radiation effects in mammalian cells; (5) radiation carcinogenesis and radioprotectors; (6) life shortening, tumor induction, and tissue dose for fission-neutron and gamma-ray irradiations; (7) mammalian genetics and biostatistics; (8) radiation toxicity studies; (9) hematopoiesis in chronic toxicity; (10) molecular biology studies; (11) chemical toxicology; (12) carcinogen identification and metabolism; (13) metal metabolism and toxicity; and (14) neurobehavioral chronobiology. (ACR)
Date: August 1, 1984
Creator: Barr, S.H. (ed.)
Partner: UNT Libraries Government Documents Department

Monte Carlo simulation of the turbulent transport of airborne contaminants

Description: A generalized, three-dimensional Monte Carlo model and computer code (SPOOR) are described for simulating atmospheric transport and dispersal of small pollutant clouds. A cloud is represented by a large number of particles that we track by statistically sampling simulated wind and turbulence fields. These fields are based on generalized wind data for large-scale flow and turbulent energy spectra for the micro- and mesoscales. The large-scale field can be input from a climatological data base, or by means of real-time analyses, or from a separate, subjectively defined data base. We introduce the micro- and mesoscale wind fluctuations through a power spectral density, to include effects from a broad spectrum of turbulent-energy scales. The role of turbulence is simulated in both meander and dispersal. Complex flow fields and time-dependent diffusion rates are accounted for naturally, and shear effects are simulated automatically in the ensemble of particle trajectories. An important adjunct has been the development of computer-graphics displays. These include two- and three- dimensional (perspective) snapshots and color motion pictures of particle ensembles, plus running displays of differential and integral cloud characteristics. The model's versatility makes it a valuable atmospheric research tool that we can adapt easily into broader, multicomponent systems- analysis codes. Removal, transformation, dry or wet deposition, and resuspension of contaminant particles can be readily included. (auth)
Date: September 1, 1975
Creator: Watson, C.W. & Barr, S.
Partner: UNT Libraries Government Documents Department

Influence of external winds and cloudiness on the transition layer above nocturnal valley drainage

Description: Past observations in mountain valleys during nighttime drainage conditions show the existence of a dynamically active transition layer between the locally-driven drainage flow and the upper free stream airflow. The height variations in this transition layer are analyzed with respect to external wind conditions, cloudiness, and weather. Data sets from the 1982 and 1984 Department of Energy's Atmospheric Studies in Complex Terrain (ASCOT) field experiments in Brush Creek Valley, Colorado, are used in this analysis of the transition layer.
Date: January 1, 1987
Creator: Orgill, M.M. & Barr, S.
Partner: UNT Libraries Government Documents Department

Proceedings of the atmospheric tracers and tracer application workshop

Description: In addition to presentations by participating members a general discussion was held in order to summarize and outline the goals and objectives of the workshop. A number of new low level background tracers such as heavy methanes, perfluorocarbons, multiply labeled isotopes such as /sup 13/C/sup 18/O/sub 2/, helium 3, in addition to sample collection techniques and analytical methods for various tracers were discussed. This report is a summary of discussions and papers presented at this workshop.
Date: December 1, 1979
Creator: Barr, S. & Gedayloo, T. (comps.)
Partner: UNT Libraries Government Documents Department

Meteorological analysis for Fenton Hill, 1979

Description: Three years of meteorological data have been collected at the Fenton Hill site to establish a local climatic baseline, transport and diffusion climatology, and an initial site for an eventual Valles Caldera meteorological network. Tower-based wind and temperature data at 15 m above ground were supplemented during 1979 with precipitation, humidity and pressure measurements, and a limited program of upper winds. Preliminary analysis of the data has been made to identify major topographic and meteorological driving forces affecting the local climatic variations on diurnal and seasonal time scales. The site is quite high and exposed enough tht external influences such as gradient wind flow and thunderstorms tend to dominate over purely local driving forces in determining climate. Locally generated wind circulations are identifiable at night but tend to be weak and sporadic. The presence of topographic obstacles on the 10- to 100-km scale is observed in the winds.
Date: January 1, 1981
Creator: Barr, S. & Wilson, S.K.
Partner: UNT Libraries Government Documents Department

Summary of the setting, air quality problems, and meteorological activities in the oil shale region

Description: This document discusses air quality problems that may arise in the valleys of the Uinta mountains and the Roan Ridge in the oil shale area in western Colorado and eastern Utah. A meteorological field expedition that was undertaken in August 1980 by LASL and PNL is described. (DLC)
Date: January 1, 1981
Creator: Barr, S. & Clements, W.E.
Partner: UNT Libraries Government Documents Department

Some observations of a subsynoptic scale disturbance

Description: A subsynoptic scale disturbance in the lower troposphere passed through the Georgia-South Carolina area during a field experiment in which supplementary meteorological data were available at the Savannah River Laboratory. Consistencies were noted in the fields of wind, temperature, and cloudiness, which aided in the documentation of the feature. This event is suggested as a useful case study for the application of mesoscale dynamical models.
Date: July 1, 1978
Creator: Barr, S.; Clements, W.E. & Archuleta, J.
Partner: UNT Libraries Government Documents Department

Application and development of the Four Corners air-dispersion model

Description: A model was developed to provide reasonable estimates of short-term concentrations in an area characterized by complex terrain and sparse meteorological data. The model has a number of strong points including the inclusion of drainage winds and partial penetration of elevated inversion layers and the ability to distinguish between rough and moderately rough terrain. In addition, the model is driven by a comprehensive, consistent meteorological data base. Finally, the model appears to give very good agreement with measurements on high terrain. The model's weaknesses include limited testing of the validity of parameters in very rough terrain at distances beyond 15 km or at distances beyond 50 km in moderately rough terrain. Furthermore, the model does not treat deposition, steering by terrain, or travel-time effects. Application of the model to the Four Corners area with high growth in 1995 indicates that a very large amount of development is consistent with the 1977 CAA. Furthermore, the results indicate that it is impossible to define an increment system based on the 95th percentile rather than on second highest concentration, which is equivalent to the current system.
Date: January 1, 1982
Creator: Williams, M.D.; Mangeng, C.A.; Barr, S. & Lewis, R.
Partner: UNT Libraries Government Documents Department

Effective transport velocity and plume elongation in nocturnal valley wind fields

Description: Using three atmospheric tracers the effective transport velocity and plume elongation produced by nocturnal drainage wind in three different valleys were investigated. Tracer was released in each valley in a well defined drainage wind field and sequentially sampled at downvalley locations. The effective transport velocity (V-eff) was determined from the elapsed time from the start of the release to the time when the plume concentration reached 10% of its peak value and the distance from the release site. The plume elongation factor was determined from the ratio of the width (time) of the plume at 10% of its peak value to the duration of the release. This method was chosen as an objective analysis scheme. Mean measured winds (V) were computed from surface wind instruments along the drainage flow path with values weighted by the estimated time the plume was in the wind field best represented by a measurement. The values used were from the start of release to the time of arrival at the sampler in question. V is compred to V-eff to see how reasonable an estimate of plume transport in valleys can be made from a few surface measurements in the valley. The simple tracer technique used in the studies has proven to be a good one in accomplishing the stated objective of investigating effective transport velocity and plume elongation in nocturnal valley drainage winds.
Date: January 1, 1980
Creator: Clements, W.E.; Barr, S. & Fowler, M.M.
Partner: UNT Libraries Government Documents Department

Rainout assessment: the ACRA system and summaries of simulation results. [Computer systems to estimate threats from precipitation scavenging of radioactive debris clouds from nuclear weapons]

Description: A generalized, three-dimensional, integrated computer code system was developed to estimate collateral-damage threats from precipitation-scavenging (rainout) of airborne debris-clouds from defensive tactical nuclear engagements. This code system, called ACRA for Atmospheric-Contaminant Rainout Assessment, is based on Monte Carlo statistical simulation methods that allow realistic, unbiased simulations of probabilistic storm, wind, and precipitation fields that determine actual magnitudes and probabilities of rainout threats. Detailed models (or data bases) are included for synoptic-scale storm and wind fields; debris transport and dispersal (with the roles of complex flow fields, time-dependent diffusion, and multidimensional shear effects accounted for automatically); microscopic debris-precipitation interactions and scavenging probabilities; air-to-ground debris transport; local demographic features, for assessing actual threats to populations; and nonlinear effects accumulations from multishot scenarios. We simulated several hundred representative shots for West European scenarios and climates to study single-shot and multishot sensitivities of rainout effects to variations in pertinent physical variables.
Date: September 1, 1977
Creator: Watson, C.W.; Barr, S. & Allenson, R.E.
Partner: UNT Libraries Government Documents Department

Nocturnal drainage wind characteristics in two converging air sheds

Description: During the short experimental period in the Grants Basin of Northeastern New Mexico a survey was conducted on the complex meteorology of this area. Emphasis was placed on the nocturnal drainage flow because of the potential hazards to the populated areas of Milan and Grants from the effluents of the uranium mining and milling operation in this area. This investigation has shown that the nocturnal drainage flow patterns agree with the winds predicted on the basis of the complex terrain of the area. Because of the surface cooling at night (over 25/sup 0/C during summer and about 20/sup 0/C during winter), air from elevated surrounding areas flows to the low lying regions consequently setting up a nocturnal drainage flow. This regime exists over 60% of the time during summer months and over 65% of the time during winter months with a depth generally less than 200 m. In the San Mateo air shed the drainage flow is east northeast, and in the Ambrosia Lake air shed it is from northwest. The confluence of these two air flows contributes mainly to the drainage flow through the channel formed by La Ja Mesa and Mesa Montanosa. The analysis of data collected by the recording Flats Station confirms the prediction that although the area south of the channel region broadens considerably causing a reduction in flow speed, contributions from the southside of La Jara Mesa and Mesa Montanosa partly compensate for this reduction. The position of this recording station is 15 to 20 km from the populated towns of Milan and Grants. A drainage flow speed of approximately 2.2 m s/sup -1/ and the duration of over 11 hours as recorded by this station indicates that air from the San Mateo and Ambrosia Lake regions may be transported southwards to these population centers ...
Date: January 1, 1980
Creator: Gedayloo, T.; Clements, W.E.; Barr, S. & Archuleta, J.A.
Partner: UNT Libraries Government Documents Department

Comparison of atmospheric temperature structure at the wall and in the middle of a valley

Description: Previously reported results indicate that measurements of temperatures near ground level on hillsides and valley walls serve as a reasonable approximation to the ambient nocturnal lapse rates. At Anderson Creek Valley in the Geysers area of California temperatures on the valley wall were compared with temperature profiles in the middle of the valley. An ensemble of temperature measurements including vertical soundings and surface based measurements from fixed stations and a mobile unit were analyzed. Although intercalibration was not rigorously conducted between the various systems, each system was calibrated independently and sufficient agreement exists when sensors were co-located to support confidence in the measurements. Surface measurements at various altitudes in Anderson Creek Valley were as much as 10/sup 0/C cooler than the temperature in mid-valley at the same altitude. The departures were smallest in the early evening and grew during the night. The cold air was quite shallow and if care were taken to make ground-based measurements on promontaries or towers, the gross stability could be characterized by surface temperature observations up the side of the valley. A more promising analysis of the data is to interpret the thermal gradients from the valley wall to the center in terms of the driving force they provide to the drainage flow. The circulations theorem of Bjerknes provides the link between the stable temperature gradients on sloping ground and the velocity field through pressure-density solenoids. By applying the theorem and accounting for frictional drag effects at the surface, a drainage domain about 100 m in depth with a speed of 4 m s/sup -1/ at TVR is estimated. Measured with profiles at that location show quite good agreement in a sublayer although larger scale driving forces account for a complex structure of wind speed and direction above the 100 to 200 m layer. (JGB)
Date: January 1, 1980
Creator: Barr, S.; Clements, W.E. & Wilson, S.K.
Partner: UNT Libraries Government Documents Department

Summertime nocturnal drainage flow in the San Mateo and Ambrosia lake air sheds of the grants basin. [Data used for determination of /sup 222/Rn transport from local uranium operations]

Description: An initial study of some fundamental meteorological properties of two major air sheds in the Grants Basin of northwestern New Mexico was conducted from May 18 to September 19, 1978. Three mechanical weather stations were used in conjunction with a few vertical wind soundings to develop a data set for the summer regime. Data collected between May 18 and July 30 is analyzed to investigate nocturnal drainage flows, daytime flows, and channeling of synoptic wind. Drainage wind averaging 2.5 m s/sup -1/ was found to exist in a surface layer not greater than 200 m deep on 60% of the nights investigated. This frequently occurring drainage flow is characterized by a strong decoupling from the upper level winds. Daytime winds, on the other hand, are representative of the synoptic flow patterns suggesting a rather rapid coupling after sunrise.
Date: January 1, 1979
Creator: Gedayloo, T.; Barr, S.; Clements, W.E. & Wilson, S.K.
Partner: UNT Libraries Government Documents Department

Some atmospheric tracer experiments in complex terrain at LASL: experimental design and data. [Fluorescent particle tracer study]

Description: Two series of atmospheric tracer experiments were conducted in complex terrain situations in and around the Los Alamos Scientific Laboratory. Fluorescent particle tracers were used to investigate nighttime drainage flow in Los Alamos Canyon and daytime flow across the local canyon-mesa complex. This report describes the details of these experiments and presents a summary of the data collected. A subsequent report will discuss the analysis of these data.
Date: March 1, 1978
Creator: Archuleta, J.; Barr, S.; Clements, W.E.; Gedayloo, T. & Wilson, S.K.
Partner: UNT Libraries Government Documents Department

Towing tank studies of stratified flow over ridges and valleys

Description: Stable atmospheric flow over a ridge and a valley was simulated in a large towing tank filled with stratified salt water. Flow visualization experiments were conducted using colored dye streamers and 10 cm high models with sinusoidal cross-sections. These experiments provided qualitative data on the structure of the flow field over the ridges and within the valley. They also provided quantitative data on the height of the dividing streamline which separates the fluid that flows over a ridge from that which flows around the ends. These data agree with an existing theory based upon the potential energy barrier associated with flow over the ridge. 9 references, 16 figures.
Date: January 1, 1984
Creator: Lee, J.T.; Barr, S.; Lawson, R.E. Jr.; Snyder, W.H. & Marsh, G.L.
Partner: UNT Libraries Government Documents Department

Drainage flow over complex terrain

Description: Model calculations even carried in order to simulate tracer release experiments at the Geysers Area. Comparisons with the experimental data provide a test of current ability to model pollutant transport. The calculations were carried out with a windfield code (ATMOS1) and an advection-diffusion code (ATMOS2). The resulting concentrations permit prediction of tracer particle collections at the measurement stations. Comparison of the observations and predictions of sequential and integrated counts shows generally good agreement, but with discrepancies in some instances. The method appears to be a useful one for pollutant transport predictions and for parametric studies.
Date: January 1, 1981
Creator: Davis, C.G.; Bunker, S.S.; King, D.S.; Mutschlecner, J.P.; Barr, S. & Clements, W.E.
Partner: UNT Libraries Government Documents Department

Data/model integration for vertical mixing in the stable Arctic boundary layer

Description: This is the final report of a short Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Data on atmospheric trace constituents and the vertical structure of stratus clouds from a 1996 expedition to the central Arctic reveal mechanisms of vertical mixing that have not been observed in mid-latitudes. Time series of the altitude and thickness of summer arctic stratus have been observed using an elastic backscatter lidar aboard an icebreaker. With the ship moored to the pack ice during 14 data collection stations and the lidar staring vertically, the time series represent advected cloud fields. The lidar data reveal a significant amount of vertical undulation in the clouds, strongly suggestive of traveling waves in the buoyantly damped atmosphere that predominates in the high Arctic. Concurrent observations of trace gases associated with the natural sulfur cycle (dimethyl sulfide, SO{sub 2}, NH{sub 3}, H{sub 2}O{sub 2}) and aerosols show evidence of vertical mixing events that coincide with a characteristic signature in the cloud field that may be called dropout or lift out. A segment of a cloud deck appears to be relocated from the otherwise quasicontinuous layer to another altitude a few hundred meters lower or higher. Atmospheric models have been applied to identify the mechanism that cause the dropout phenomenon and connect it dynamically to the surface layer mixing.
Date: December 31, 1998
Creator: Barr, S.; ReVelle, D.O.; Kao, C.Y.J. & Bigg, E.K.
Partner: UNT Libraries Government Documents Department

Explicit SO(10) supersymmetric grand unified model

Description: A complete set of Higgs and matter superfields is introduced with well-defined SO(10) properties and U(1) x Z{sub 2} x Z{sub 2} family charges from which the Higgs and Yukawa superpotentials are constructed. The Higgs fields solve the doublet-triplet splitting problem, while the structures of the four Dirac fermion mass matrices obtained involve just six effective Yukawa operators. The right-handed Majorana matrix arises from one Higgs field coupling to several pairs of superheavy conjugate neutrino singlets. In terms of 10 input parameters to the mass matrices, the model accurately yields the 20 masses and mixings of the lightest quarks and leptons, as well as the masses of the 3 heavy right-handed neutrinos. The bimaximal atmospheric and solar neutrino vacuum solutions are favored in this simplest version.
Date: June 23, 2000
Creator: Albright, Carl H. & Barr, S. M.
Partner: UNT Libraries Government Documents Department