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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,… more
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))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Active layer hydrology for Imnavait Creek, Toolik, Alaska

Description: The hydrology of the active layer of a watershed is described. In the annual hydrologic cycle, snowmelt is the most significant event at Imnavait Creek located near Toolik Lake, Alaska. Precipitation that has accumulated for more than 6 months on the surface melts in a relatively short period of 7 to 10 days once sustained melting occurs. Significant runoff events are few. Convective storms covering relatively small areas on the North Slope of Alaska can produce significant small-scale events i… more
Date: April 1, 1987
Creator: Hinzman, L.D. & Kane, D.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Installation restoration program: Hydrologic measurements with an estimated hydrologic budget for the Joliet Army Ammunition Plant, Joliet, Illinois. [Contains maps of monitoring well locations, topography and hydrologic basins]

Description: Hydrologic data were gathered from the 36.8-mi{sup 2} Joliet Army Ammunition Plant (JAAP) located in Joliet, Illinois. Surface water levels were measured continuously, and groundwater levels were measured monthly. The resulting information was entered into a database that could be used as part of numerical flow model validation for the site. Deep sandstone aquifers supply much of the water in the JAAP region. These aquifers are successively overlain by confining shales and a dolomite aquifer of… more
Date: July 1, 1991
Creator: Diodato, D. M.; Cho, H. E. & Sundell, R. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evapotranspiration studies for protective barriers: FY 1990 status report

Description: Pacific Northwest Laboratory (PNL) and Westinghouse Hanford Company (Westinghouse Hanford) are working together to develop for the US Department of Energy (DOE) protective barriers for the near-surface disposal of hazardous waste at the Hanford Site. The proposed barrier design consists of a layer of fine-textured soil overlying a series of layers grading from sand to basalt riprap. A multiyear research program is being conducted to assess the long-term performance of barrier configurations in … more
Date: May 1, 1992
Creator: Link, S.O.; Downs, J.L.; Thiede, M.E.; Lettau, D.J.; Twaddell, T.R. (Pacific Northwest Lab., Richland, WA (United States)) & Black, R.A. (Washington State Univ., Pullman, WA (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cultivation of Macroscopic Marine Algae and Freshwater Aquatic Needs. Progress Report, May 1, 1979-December 15, 1979

Description: Progress for the period May 1979 to December 1979 is reported in the following subject areas: (1) the ORCA clone of the red seaweed Gracilaria tikvakiae has now been grown continuously in tank culture for two years; (2) studies were continued on the culture of freshwater plants such as water hyacinth, pennywort, water lettuce, and duckweed; (3) the loss of water from evapotranspiration of freshwater plants was measured and compared with water loss from evaporation from open water; and (4) exper… more
Date: January 1, 1980
Creator: Ryther, J. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaportranspiration studies for protective barriers: FY 1989 status report

Description: This document describes the results of technological developments and experiments at the Small Tube Lysimeter Facility. The objective of this research is to develop the capability to predict evapotranspiration in support of studies of water infiltration control for the Hanford Protective Barrier Development Program. Evapotranspiration is the combined loss of water from plants and soil surfaces to the atmosphere. This process must be predictable to adequately model soil water dynamics. We develo… more
Date: May 1, 1992
Creator: Link, S.O.; Thiede, M.E.; Downs, J.L.; Lettau, D.J. (Pacific Northwest Lab., Richland, WA (United States)) & Waugh, W.J. (Geotech, Grand Junction, CO (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evapotranspiration studies for protective barriers: Experimental plans

Description: This document describes a general theory and experimental plans for predicting evapotranspiration in support of the Protective Barrier Program. Evapotranspiration is the combined loss of water from plants and soil surfaces to the atmosphere. 45 refs., 1 fig., 4 tabs.
Date: November 1, 1989
Creator: Link, S.O. & Waugh, W.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of plants on sunspace passive solar heating

Description: The effect of plants on sunspace thermal performance is investigated, based on experiments done in Los Alamos using two test rooms with attached sunspaces, which were essentially identical except for the presence of plants in one. Performance is related to plant transpiration, evaporation from the soil, condensation on the glazing and the absorbtance of solar energy by the lightweight leaves. Performance effects have been quantified by measurements of auxiliary heat consumption in the test room… more
Date: January 1, 1985
Creator: Best, E.D. & McFarland, R.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tritium migration studies at the Nevada Test Site

Description: Emanation of tritium from waste containers is a commonly known phenomenon. Release of tritium from buried waste packages was anticipated, therefore a research program was developed to study both the rate of tritium release from buried containers and subsequent migration of tritium through soil. Migration of tritium away from low level radioactive wastes buried in Area 5 of the Nevada Test Site was studied. Four distinct disposal events were investigated. The oldest burial event studied was a 19… more
Date: August 1, 1991
Creator: Schulz, R. K.; Romney, E. M.; Fujii, L. M.; Greger, P. D.; Kendall, E. W. & Hunter, R.B. (Reynolds Electrical and Engineering Co., Inc., Las Vegas, NV (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Annual dynamics within the active layer

Description: We have continued our meteorological and hydrologic data collection in support of our process-oriented research. The six years of data collected to date is unique in its scope and continuity in a North Hemisphere Arctic setting. This valuable data base has allowed us to further our understanding of the interconnections and interactions between the atmosphere/hydrosphere/biosphere/lithosphere. The increased understanding of the heat and mass transfer processes has allowed us to increase our mode… more
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The evaporative fraction as a measure of surface energy partitioning

Description: The evaporative fraction is a ratio that expresses the proportion of turbulent flux energy over land surfaces devoted to evaporation and transpiration (evapotranspiration). It has been used to characterize the energy partition over land surfaces and has potential for inferring daily energy balance information based on mid-day remote sensing measurements. The HAPEX-MOBILHY program's SAMER system provided surface energy balance data over a range of agricultural crops and soil types. The databases… more
Date: January 1, 1990
Creator: Nichols, W.E. (Pacific Northwest Lab., Richland, WA (United States)) & Cuenca, R.H. (Oregon State Univ., Corvallis, OR (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Detecting vegetation-precipitation feedbacks in mid-Holocene North Africa from two climate models

Description: Using two climate-vegetation model simulations from the Fast Ocean Atmosphere Model (FOAM) and the Community Climate System Model (CCSM, version 2), we investigate vegetation-precipitation feedbacks across North Africa during the mid-Holocene. From mid-Holocene snapshot runs of FOAM and CCSM2, we detect a negative feedback at the annual timescale with our statistical analysis. Using the Monte- Carlo bootstrap method, the annual negative feedback is further confirmed to be significant in both si… more
Date: March 31, 2008
Creator: Wang, Yi; Notaro, Michael; Liu, Zhengyu; Gallimore, Robert; Levis, Samuel & Kutzbach, John E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Use of a dynamic simulation model to understand nitrogen cycling in the middle Rio Grande, NM.

Description: Water quality often limits the potential uses of scarce water resources in semiarid and arid regions. To best manage water quality one must understand the sources and sinks of both solutes and water to the river system. Nutrient concentration patterns can identify source and sink locations, but cannot always determine biotic processes that affect nutrient concentrations. Modeling tools can provide insight into these large-scale processes. To address questions about large-scale nitrogen removal … more
Date: August 1, 2008
Creator: Meixner, Tom (University of Arizona, Tucson, AZ); Tidwell, Vincent Carroll; Oelsner, Gretchen (University of Arizona, Tucson, AZ); Brooks, Paul (University of Arizona, Tucson, AZ) & Roach, Jesse D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparative simulations of a two-layer landfill barrier using the HELP Version 2. 0 and UNSAT-H Version 2. 0 computer codes

Description: This report documents the results of a simulation of the performance of a two-layer infiltration barrier for a nonradioactive dangerous waste landfill (NRDWL) at the US Department of Energy's Hanford Site in semi-arid southeast Washington State. The performance of the barrier was simulated for a period of 10 years using the UNSAT-H version 2.0 groundwater flow computer code. Pacific Northwest Laboratory performed this simulation to compare results using UNSAT-H 2.0 with those of the US Env… more
Date: January 1, 1991
Creator: Nichols, W.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pacific Northwest Laboratory: Annual report for 1986 to the DOE Office of Energy Research: Part 2, Environmental sciences

Description: This report summarizes progress in environmental sciences research conducted by Pacific Northwest Laboratory (PNL) for the Office of Health and Environmental Research in FY 1986. The program is focused on terrestrial, subsurface, and coastal marine systems, and this research forms the basis, in conjunction with remote sensing, for definition and quantification of processes leading to impacts at the global level. This report is organized into sections devoted to Detection and Management of Chang… more
Date: September 1, 1987
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Plant Research '75

Description: Research is reported on stomatal regulation of the gas exchanges between plant and environment; inhibitory effects in flower formation; plant growth and development through hormones; hormone action; development and nitrogen fixation in algae; primary cell wall glycoprotein ectensin; enzymic mechanisms and control of polysaccharide and glycoprotein synthesis; molecular studies of membrane studies; sensory transduction in plants; regulation of formation of protein complexes and enzymes in higher … more
Date: January 1, 1975
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Use of CREAMS model in experimental designs for shallow land burial of low level wastes

Description: A state-of-the art model developed by the US Department of Agriculture called CREAMS (A Field Scale Model for Chemicals, Runoff, and Erosion from Agricultural Management Systems) is used to simulate the hydrologic processes in soil and rock covers at shallow land waste disposal sites. Application of the CREAMS model in management of soil moisture and percolation at waste disposal sites is discussed for diverse topsoil-backfill-cobble-gravel trench cap designs tested at different field scales. 8… more
Date: January 1, 1985
Creator: Devaurs, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Field Lysimeter Test Facility: Protective barrier test results (FY 1990, the third year)

Description: The Field Lysimeter Test Facility (FLTF) was constructed to test protective barriers for isolating low-level radioactive and hazardous wastes from the biosphere. Protective barriers are specially configured earth materials placed over near-surface wastes to prevent intrusion of water, plants, and animals. Low-level radioactive waste is stored in near-surface repositories at the Hanford Site and can be transported into the biosphere by water, plants, and animals. The purpose of the FLTF is to me… more
Date: November 1, 1990
Creator: Campbell, M.D. & Gee, G.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evapotranspiration studies for protective barriers: FY 1988 status report

Description: In FY 1988, evapotranspiration studies in support of the Protective Barrier Development Program focused on developing instruments to measure evapotranspiration and on conducting natural analog studies. This report describes a has exchange chamber being developed that will control internal temperature and relative humidity to simulate outdoor conditions. This device will measure evapotranspiration rates unambiguously from any surface and measure carbon dioxide exchange rates, which will provide … more
Date: May 1990
Creator: Link, S. O.; Thiede, M. E.; Evans, R. D.; Downs, J. L. & Waugh, W. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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GROW1: a crop growth model for assessing impacts of gaseous pollutants from geothermal technologies

Description: A preliminary model of photosynthesis and growth of field crops was developed to assess the effects of gaseous pollutants, particularly airborne sulfur compounds, resulting from energy production from geothermal resources. The model simulates photosynthesis as a function of such variables as irradiance, CO/sub 2/ diffusion resistances, and internal biochemical processes. The model allocates the products of photosynthesis to structural (leaf, stem, root, and fruit) and storage compartments of th… more
Date: March 17, 1977
Creator: Kercher, J.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Protective barrier climate-change impacts: Technical workshop findings and recommendations

Description: A workshop was convened to define key issues regarding the impacts of climatic variability on the performance of protective layered soil and rock barriers proposed for possible use at Hanford. Workshop participants concluded that the sensitivity of vegetation and evapotranspiration to climate must be better understood before climate-change impacts on drainage through the barrier and groundwater recharge can be adequately modeled. As a result of this conclusion, workshop participants proposed me… more
Date: December 1, 1988
Creator: Waugh, W. J. & Foley, M. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Arid site water balance: evapotranspiration modeling and measurements

Description: In order to evaluate the magnitude of radionuclide transport at an aird site, a field and modeling study was conducted to measure and predict water movement under vegetated and bare soil conditions. Significant quantities of water were found to move below the roo of a shallow-rooted grass-covered area during wet years at the Hanford site. The unsaturated water flow model, UNSAT-1D, was resonably successful in simulating the transient behavior of the water balance at this site. The effects of la… more
Date: September 1, 1984
Creator: Gee, G.W. & Kirkham, R.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Active layer hydrology for Imnavait Creek, Toolik, Alaska

Description: The hydrology of the active layer of a watershed is described. In the annual hydrologic cycle, snowmelt is the most significant event at Imnavait Creek located near Toolik Lake, Alaska. Precipitation that has accumulated for more than 6 months on the surface melts in a relatively short period of 7 to 10 days once sustained melting occurs. Significant runoff events are few. Convective storms covering relatively small areas on the North Slope of Alaska can produce significant small-scale events i… more
Date: April 1, 1987
Creator: Hinzman, L. D. & Kane, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Comparison of ground-derived and satellite-derived surface energy fluxes from a shrub-steppe site

Description: Efforts to measure evapotranspiration (ET) remotely are common in agriculture, and the application of such data to irrigation scheduling is readily apparent. Extending this methodology to arid environments is primarily of use as a mechanism for validation of ET algorithms used in large-scale watershed and global climate change modeling efforts. To facilitate testing of the remote sensing method for ET, measurements of sensible and latent heat flux were made at four sites located on the US Depar… more
Date: March 1, 1994
Creator: Kirkham, R. R.; Gee, G. W. & Fritschen, L. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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