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Development of an arid site closure plan

Description: This document describes the development of a prototype plan for the effective closure and stabilization of an arid low-level waste disposal site. This plan will provide demonstrated closure techniques for a trench in a disposal site at Los Alamos. The accuracy of modeling soil water storage by two hydrologic models, CREAMS and HELP, was tested by comparing simulation results with field measurements of soil moisture in eight experimental landfill cover systems having a range of well-defined soil profiles and vegetative covers. Regression analysis showed that CREAMS generally represented soil moisture more accurately than HELP simulations. Precautions for determining parameter values for model input and for interpreting simulation results are discussed. A specific example is presented showing how the field-validated hydrologic models can be used to develop a final prototype closure plan. 15 refs., 13 figs., 3 tabs.
Date: January 1, 1987
Creator: Nyhan, J.W. & Barnes, F.J.
Partner: UNT Libraries Government Documents Department

Hydrologic modeling of soil water storage in landfill cover systems

Description: The accuracy of modeling soil water storage by two hydrologic models, CREAMS and HELP, was tested by comparing simulation results with field measurements of soil moisture in eight experimental landfill cover systems having a range of well-defined soil profiles and vegetative covers. Regression analysis showed that CREAMS generally represented soil moisture more accurately than HELP simulations. Soil profiles that more closely resembled natural agricultural soils were more accurately modeled than highly artificial layered soil profiles. Precautions for determining parameter values for model input and for interpreting simulation results are discussed.
Date: January 1, 1987
Creator: Barnes, F.J. & Rodgers, J.C.
Partner: UNT Libraries Government Documents Department

Effects of vegetation and soil-surface cover treatments on the hydrologic behavior of low-level waste trench caps

Description: Preliminary results are presented on a three-year field study at Los Alamos National Laboratory to evaluate the influence of different low-level radioactive waste trench cap designs on water balance under natural precipitation. Erosion plots having two different vegetative covers (shrubs and grasses) and with either gravel-mulched or unmulched soil surface treatments have been established on three different soil profiles on a decommissioned waste site. Total runoff and soil loss from each plot is measured after each precipitation event. Soil moisture is measured biweekly while plant canopy cover is measured seasonally. Preliminary results from the first year show that the application of a gravel mulch reduced runoff by 73 to 90%. Total soil loss was reduced by 83 to 93% by the mulch treatment. On unmulched plots, grass cover reduced both runoff and soil loss by about 50% compared to the shrub plots. Continued monitoring of the study site will provide data that will be used to analyze complex interactions between independent variables such rainfall amount and intensity, antecedent soil moisture, and soil and vegetation factors, as they influence water balance, and soil erosion. 18 refs., 2 figs., 3 tabs.
Date: January 1, 1988
Creator: Lopez, E.A.; Barnes, F.J. & Antonio, E.J.
Partner: UNT Libraries Government Documents Department

Role of water balance in the long-term stability of hazardous waste site cover treatments

Description: After the 30-year post-closure maintenance period at hazardous waste landfills, long-term stability must be assured without continued intervention. Understanding water balance in the established vegetative cover system is central to predicting such stability. A Los Alamos National Laboratory research project has established a series of experimental cover treatment plots on a closed waste disposal site which will permit the determination of the effects of such critical parameters as soil cover design, leaf area index, and rooting characteristics on water balance under varied conditions. Data from these experiments are being analyzed by water balance modeling and other means. The results show consistent differences in soil moisture storage between soil profiles and between vegetation cover treatments.
Date: January 1, 1986
Creator: Barnes, F.J.; Rodgers, J.C. & Trujillo, G.
Partner: UNT Libraries Government Documents Department

Developing public awareness for climate change: Support from international research programs

Description: Developing regional and local public awareness and interest in global climate change has been mandated as an important step for increasing the ability for setting policy and managing the response to climate change. Research programs frequently have resources that could help reach regional or national goals for increasing the capacity for responding to climate change. To obtain these resources and target recipients appropriately, research investigators need clear statements of national and regional strategies or priorities as a guide. One such program, the Atmospheric Radiation Measurement (ARM) Program, has a requirement to develop local or regional education enrichment programs at their observational sites in the central US, the tropical western Pacific (TWP), and on the north slope of alaska. ARM's scientific goals will result in a flow of technical data and as well as technical expertise that can assist with regional needs to increase the technical resources needed to address climate change issues. Details of the ARM education program in the Pacific will be presented.
Date: December 31, 1998
Creator: Barnes, F.J. & Clements, W.E.
Partner: UNT Libraries Government Documents Department

Variation in runoff and erosion rates from different trench cap cover systems

Description: A field-scale demonstration study was established at Los Alamos National Laboratory to evaluate the interactive effects of soil surface mulches and type of vegetative cover on site water balance and erosion under natural precipitation conditions. The study was established on an inactive, low-level radioactive waste site, and consists of clusters of plots on 3 different soil profiles. Each cluster consists of two pairs of plots. Each pair of plots has either shrub or grass vegetative cover, and one plot of each pair received a gravel surface mulch at the time of insulation. Soil moisture was measured biweekly, and plant and soil surface cover were measured seasonally. Total runoff and sediment transport from each plot was measured after each precipitation event or each snowmelt event. Data from 1987 and 1988 show increased stabilization of the soil surface with time. Runoff and sediment transport is five to ten times greater on unmulched plots in comparison to plots with a gravel mulch. Higher precipitation than usual in 1988 resulted in erosion rates that exceeded tolerance limits on several unmulched plots. Runoff from snowmelt was greater on mulched plots, and generally had low sediment concentrations. Continued monitoring of the site through 1989 will result in a unique data base of the effects of natural precipitation and different cover designs on site performance. 10 refs., 1 fig., 3 tabs.
Date: January 1, 1989
Creator: Lopez, E.A.; Barnes, F.J.; Kincaid, M.L. & Antonio, E.J.
Partner: UNT Libraries Government Documents Department

Boundary layer structure over areas of heterogeneous heat fluxes

Description: In general circulation models (GCMs), some properties of a grid element are necessarily considered homogeneous. That is, for each grid volume there is associated a particular combination of boundary layer depth, vertical profiles of wind and temperature, surface fluxes of sensible and latent heat, etc. In reality, all of these quantities may exhibit significant spatial variations within the grid area, and the larger the area the greater the likely variations. In balancing the benefits of higher resolution against increased computational time and expense, it is useful to consider what the consequences of such subgrid-scale variability may be. Moveover, in interpreting the results of a simulation, one must be able to define an appropriate average value over a grid. There are two aspects of this latter problem: (1) in observations, how does one take a set of discrete or volume-averaged measurements and relate these to properties of the entire domain, and (2) in computations, how can subgrid-scale features be accounted for in the model parameterizations? To address these and related issues, two field campaigns were carried out near Boardman, Oregon, in June 1991 and 1992. These campaigns were designed to measure the surface fluxes of latent and sensible heat over adjacent areas with strongly contrasting surface types and to measure the response of the boundary layer to those fluxes. This paper discuses some initial findings from those campaigns.
Date: April 1, 1993
Creator: Doran, J. C.; Barnes, F. J.; Coulter, R. L. & Crawford, T. L.
Partner: UNT Libraries Government Documents Department

Boundary layer structure over areas of heterogeneous heat fluxes

Description: In general circulation models (GCMs), some properties of a grid element are necessarily considered homogeneous. That is, for each grid volume there is associated a particular combination of boundary layer depth, vertical profiles of wind and temperature, surface fluxes of sensible and latent heat, etc. In reality, all of these quantities may exhibit significant spatial variations the grid area, and the larger the area the greater the likely variations. In balancing the benefits of higher resolution against increased computational time and expense, it is useful to consider what the consequences of such subgrid-scale variability may be. Moreover, in interpreting the results of a simulation, one must be able to define an appropriate average value over a grid. There are two aspects of this latter problem: (1) in observations, how does one take a set of discrete or volume-averaged measurements and relate these to properties of the entire domain, and (2) in computations, how can subgrid-scale features be accounted for in the model parameterizations? To address these and related issues, two field campaigns were carried out near Boardman, Oregon, in June 1991 and 1992. These campaigns were designed to measure the surface fluxes of latent and sensible heat over adjacent areas with strongly contrasting surface types and to measure the response of the boundary layer to those fluxes. This paper discusses some initial findings from those campaigns.
Date: January 1, 1993
Creator: Doran, J. C.; Barnes, F. J.; Coulter, R. L. & Crawford, T. L.
Partner: UNT Libraries Government Documents Department

A field study of the effects of inhomogeneities of surface sensible and latent heat fluxes

Description: In recent years, the problem of characterizing turbulent fluxes of heat, momentum, and moisture over inhomogeneous surfaces has received increasing attention. This issue is relevant to the performance of general circulation models (GCMs), in which a single grid element can encompass a variety of surface and topographical features. Although considerable progress has been made in describing the energy balance at a surface partially covered by vegetation, less is known about how to treat adjacent regions of sharply contrasting surface characteristics. One difficulty is the scarcity of suitable data sets with which to study the problem, particularly on scales of tens to hundreds of kilometers.
Date: January 1, 1992
Creator: Doran, J. C.; Barnes, F. J.; Coulter, R. L. & Crawford, T. L.
Partner: UNT Libraries Government Documents Department

Fluxes of water and energy in physically heterogeneous environments

Description: This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Fluxes of water and energy at the near-surface environment are tightly interrelated with a heterogeneous vegetation pattern that is a mosaic of tree canopies and intercanopy area. The objective was to improve the ability to predict these interrelationships, which are not well quantified. The authors (1) quantified how vegetation overstory determines the patterns of soil moisture and near-ground solar radiation, (2) developed spatial neighborhood analyses that demonstrated how woody plants exploit canopy/intercanopy heterogeneity, (3) developed a spatially explicit model for predicting near-ground solar radiation for sites along a grassland-forest continuum, (4) developed a water balance model that predicted temporal shifts in soil moisture between canopy and intercanopy patches, and (5) used the collective results to assess large-scale ecosystem responses to climate variations that lead to accelerated soil erosion.
Date: November 1, 1997
Creator: Breshears, D.D.; Barnes, F.J. & Davenport, D.W.
Partner: UNT Libraries Government Documents Department

The ARM program in the Tropical Western Pacific

Description: The Department of Energy`s Atmospheric Radiation Measurement (ARM) Program was created in 1989 as part of the US Global Change Research Program to improve the treatment of atmospheric radiative and cloud processes in computer models used to predict climate change. The overall goal of the ARM program is to develop and test parameterizations of important atmospheric processes, particularly cloud and radiative processes, for use in atmospheric models. This goal is being achieved through a combination of field measurements and modeling studies. Three primary locales were chosen for extensive field measurement facilities. These are the Southern Great Plains of the United States, the Tropical Western Pacific, and the North Slope of Alaska and Adjacent Arctic Ocean. This paper describes the ARM program in the Tropical Western Pacific locale.
Date: December 1, 1998
Creator: Clements, W.E.; Barnes, F.J.; Ackerman, T.P. & Mather, J.H.
Partner: UNT Libraries Government Documents Department

Surface fluxes important to cloud development

Description: To address some of the issues in scaling and averaging of measurements, collaborative field campaigns were conducted in June 1991 and 1992 by the DOE laboratories funded under the ARM program. We selected a site in Boardman, OR, with two distinct regions where the sensible and latent heat fluxes would differ sharply and where each region was sufficiently extensive for full development of boundary layers and for utilizing aircraft-mounted instrument systems (Barnes et al. 1992, Doran et al. 1992). Measurements were clustered along a 16-km transect across adjoining irrigated farmland and semi-arid rangeland regions that allowed the collaborating teams to conduct a variety of studies relating to overall goals. The Los Alamos team efforts were focused on assessing the effects of different surface characteristics on fluxes of heat and water vapor.
Date: January 1, 1993
Creator: Barnes, F.J.; Porch, W. (Los Alamos National Lab., NM (United States)) & Kunkel, K.E. (Illinois State Water Survey, Champaign, IL (United States))
Partner: UNT Libraries Government Documents Department

Variability of surface fluxes over a heterogeneous semi-arid grassland

Description: Efforts are increasing throughout the research community to improve the predictive capabilities of general circulation models (GCMs). The US Department of Energy's Atmospheric Radiation Measurement (ARM) program has stated its goals as improving the representation and parameterization of cloud radiative forcing and feedbacks in GCMs by a combined modeling and experimental approach. Along with ambient atmospheric conditions, including advection of water vapor and cloud nuclei from other regions, cloud dynamics depend on surface fluxes of heat and water vapor. The lower boundary of the GCM modeling domain, the earth's surface, exerts a strong influence on regional dynamics of heat and water vapor, and the heterogeneity in the surface features can be responsible for generating regional mesoscale circulation patterns. Changes in the surface vegetation due to anthropogenic activity can cause substantial changes in the ratio of sensible to latent heat flux and result in climate changes that may be irreversible. A broad variety of models for representing energy fluxes are in use, from individual leaf and canopy models to mesoscale atmospheric models and GCMs. Scaling-up a model is likely to result in significant errors, since biophysical responses often have nonlinear dependence on the abiotic environment. Thus, accurate and defensible methods for selecting measurement scales and modeling strategies are needed in the effort to improve GCMs. 7 refs., 4 figs., 1 tab.
Date: January 1, 1991
Creator: Barnes, F.J.; Porch, W.; Cooper, D. (Los Alamos National Lab., NM (United States)); Kunkel, K.E. (Illinois Univ., Urbana, IL (United States)); Hipps, L. & Swiatek, E. (Utah State Univ., Logan, UT (United States))
Partner: UNT Libraries Government Documents Department

Boundary layer structure over areas of heterogeneous heat fluxes

Description: In general circulation models (GCMs), some properties of a grid element are necessarily considered homogeneous. That is, for each grid volume there is associated a particular combination of boundary layer depth, vertical profiles of wind and temperature, surface fluxes of sensible and latent heat, etc. In reality, all of these quantities may exhibit significant spatial variations within the grid area, and the larger the area the greater the likely variations. In balancing the benefits of higher resolution against increased computational time and expense, it is useful to consider what the consequences of such subgrid-scale variability may be. Moveover, in interpreting the results of a simulation, one must be able to define an appropriate average value over a grid. There are two aspects of this latter problem: (1) in observations, how does one take a set of discrete or volume-averaged measurements and relate these to properties of the entire domain, and (2) in computations, how can subgrid-scale features be accounted for in the model parameterizations To address these and related issues, two field campaigns were carried out near Boardman, Oregon, in June 1991 and 1992. These campaigns were designed to measure the surface fluxes of latent and sensible heat over adjacent areas with strongly contrasting surface types and to measure the response of the boundary layer to those fluxes. This paper discuses some initial findings from those campaigns.
Date: January 1, 1993
Creator: Doran, J.C. (Pacific Northwest Lab., Richland, WA (United States)); Barnes, F.J. (Los Alamos National Lab., NM (United States)); Coulter, R.L. (Argonne National Lab., IL (United States)) & Crawford, T.L. (National Oceanic and Atmospheric Administration, Oak Ridge, TN (United States). Air Resources Lab. Atmospheric Turbulence and Diffusion Div.)
Partner: UNT Libraries Government Documents Department

Boundary layer structure over areas of heterogeneous heat fluxes

Description: In general circulation models (GCMs), some properties of a grid element are necessarily considered homogeneous. That is, for each grid volume there is associated a particular combination of boundary layer depth, vertical profiles of wind and temperature, surface fluxes of sensible and latent heat, etc. In reality, all of these quantities may exhibit significant spatial variations the grid area, and the larger the area the greater the likely variations. In balancing the benefits of higher resolution against increased computational time and expense, it is useful to consider what the consequences of such subgrid-scale variability may be. Moreover, in interpreting the results of a simulation, one must be able to define an appropriate average value over a grid. There are two aspects of this latter problem: (1) in observations, how does one take a set of discrete or volume-averaged measurements and relate these to properties of the entire domain, and (2) in computations, how can subgrid-scale features be accounted for in the model parameterizations To address these and related issues, two field campaigns were carried out near Boardman, Oregon, in June 1991 and 1992. These campaigns were designed to measure the surface fluxes of latent and sensible heat over adjacent areas with strongly contrasting surface types and to measure the response of the boundary layer to those fluxes. This paper discusses some initial findings from those campaigns.
Date: January 1, 1993
Creator: Doran, J.C. (Pacific Northwest Lab., Richland, WA (United States)); Barnes, F.J. (Los Alamos National Lab., NM (United States)); Coulter, R.L. (Argonne National Lab., IL (United States)) & Crawford, T.L. (National Oceanic and Atmospheric Administration, Oak Ridge, TN (United States). Air Resources Lab. Atmospheric Turbulence and Diffusion Div.)
Partner: UNT Libraries Government Documents Department