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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
open access

Annual dynamics within the active layer. Annual progress report, March 15, 1990--March 14, 1991

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: December 31, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Description of heat flux measurement methods used in hydrocarbon and propellant fuel fires at Sandia.

Description: The purpose of this report is to describe the methods commonly used to measure heat flux in fire applications at Sandia National Laboratories in both hydrocarbon (JP-8 jet fuel, diesel fuel, etc.) and propellant fires. Because these environments are very severe, many commercially available heat flux gauges do not survive the test, so alternative methods had to be developed. Specially built sensors include 'calorimeters' that use a temperature measurement to infer heat flux by use of a model (he… more
Date: December 1, 2010
Creator: Nakos, James Thomas
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Shallow infiltration processes in arid watersheds at Yucca Mountain, Nevada

Description: A conceptual model of shallow infiltration processes at Yucca Mountain, Nevada, was developed for use in hydrologic flow models to characterize net infiltration (the penetration of the wetting front below the zone influenced by evapotranspiration). The model categorizes the surface of the site into four infiltration zones. These zones were identified as ridgetops, sideslopes, terraces, and active channels on the basis of water-content changes with depth and time. The maximum depth of measured w… more
Date: December 31, 1994
Creator: Flint, L.E. & Flint, A. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Auxiliary analyses in support of performance assessment of a hypothetical low-level waste disposal facility: Application of an infiltration evaluation methodology. Volume 1

Description: This report provides an analysis of infiltration and percolation at a hypothetical low-level waste (LLW) disposal facility was carried out. The analysis was intended to illustrate general issues of concern in assessing the performance of LLW disposal facilities. Among the processes considered in the analysis were precipitation, runoff, information, evaporation, transpiration, and redistribution. The hypothetical facility was located in a humid environment characterized by frequent and often int… more
Date: December 1, 1993
Creator: Meyer, P.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Verification of a 1-dimensional model for predicting shallow infiltration at Yucca Mountain

Description: A characterization of net infiltration rates is needed for site-scale evaluation of groundwater flow at Yucca Mountain, Nevada. Shallow infiltration caused by precipitation may be a potential source of net infiltration. A 1-dimensional finite difference model of shallow infiltration with a moisture-dependant evapotranspiration function and a hypothetical root-zone was calibrated and verified using measured water content profiles, measured precipitation, and estimated potential evapotranspiratio… more
Date: December 31, 1994
Creator: Hevesi, Joseph A.; Flint, Alan L. & Flint, Lorraine E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Evaluation of precipitation predictions in a regional climate simulation

Description: The research reported here is part of a larger project that is coupling a suite of environmental models to simulate the hydrologic cycle within river basins (Bossert et al., 1999). These models include the Regional Atmospheric Modeling System (RAMS), which provides meteorological variables and precipitation to the Simulator for Processes of Landscapes, Surface/Subsurface Hydrology (SPLASH). SPLASH partitions precipitation into evaporation, transpiration, soil water storage, surface runoff, and … more
Date: December 1, 1998
Creator: Costigan, Keeley R.; Bossert, James E. & Langely, David L.
Item Type: Refine your search to only Article
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: December 31, 1990
Creator: Nichols, W. E. & Cuenca, R. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The development of a generic model for assessing the effects of elevated CO{sub 2} on ecosystems. Progress report, September 1, 1987--May 31, 1988

Description: Nitrogen concentrations in leaves vary in response to resource availability, generally increasing with increasing light or soil nitrogen and decreasing when plants are grown at higher than ambient carbon dioxide concentrations. This decrease in leaf nitrogen which commonly occurs at elevated levels of carbon dioxide Is intriguing and important for a number of reasons. Since leaf nitrogen and photosynthetic capacity are correlated, plants grown at high levels of carbon dioxide often do not displ… more
Date: December 31, 1988
Creator: Reynolds, J. F.; Dougherty, R. L.; Harley, P. C.; Hilbert, D. W. & Skiles, J. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

[Generic ecosystem model for assessing the effects of elevated carbon dioxide on ecosystems]. [Annual] report, July 1, 1988--June 30, 1989

Description: Development of simulation models of the effects of elevated CO{sub 2} on plant physiological processes requires close cooperation between modelers and experimentalists. In particular, the detailed process-based, leaf-level photosynthesis model currently in development at San Diego State University requires parameterization data for different plant species, levels within the canopy, and growth conditions. Validation of model predictions will require additional data. The purpose of this supplemen… more
Date: December 31, 1989
Creator: Reynolds, J. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Tailoring Fe-Base Alloys for Intermediate Temperature SOFC Interconnect Application

Description: This report summarized the research efforts and major conclusions for our SECA Phase I and II project focused on Cr-free or low Cr Fe-Ni based alloy development for intermediate temperature solid oxide fuel cell (SOFC) interconnect application. Electrical conductivity measurement on bulk (Fe,Ni){sub 3}O{sub 4} coupons indicated that this spinel phase possessed a higher electrical conductivity than Cr{sub 1.5}Mn{sub 1.5}O{sub 4} spinel and Cr{sub 2}O{sub 3}, which was consistent with the low are… more
Date: December 31, 2007
Creator: Zhu, J. H.; Brady, M. P. & Anderson, H. U.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effects of Elevated Atmospheric CO{sub 2} on Canopy Transpiration in Senescent Spring Wheat

Description: The seasonal course of canopy transpiration and the diurnal courses of latent heat flux of a spring wheat crop were simulated for atmospheric CO{sub 2} concentrations of 370 {micro}mol mol{sup {minus}1} and 550 {micro}mol mol{sup {minus}1}. The hourly weather data, soil parameters and the irrigation and fertilizer treatments of the Free-Air Carbon Dioxide Enrichment wheat experiment in Arizona (1992/93) were used to drive the model. The simulation results were tested against field measurements … more
Date: December 31, 1998
Creator: Grossman, S.; Kimball, B. A.; Hunsaker, D. J.; Long, S. P.; Garcia, R. L.; Kartschall, T. H. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Carbon Dioxide and Vegetation Water Use

Description: Evapo-transpiration from vegetation, as well as patterns of precipitation are expected to change as the concentration of CO{sub 2} in the atmosphere continues to rise (f). Water modulates the rates of many biogeochemical processes, and it has been estimated that water directly limits plant productivity over two-thirds of the earth's land surface (2). Water quality and availability are increasingly important practical issues as demands by both agricultural and urban users continue to increase. I… more
Date: December 1, 1996
Creator: Ball, J.T.; Peterson, A.G.; Hoylman, A.M.; Luo, Y.; Sims, D.A.; Johnson, D.W. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Geohydrology and evapotranspiration at Franklin Lake Playa, Inyo County, California

Description: Franklin Lake playa is one of the principal discharge areas of the Furnace Creek Ranch-Alkali Flat ground-water-flow system in southern Nevada and adjacent California. Yucca Mountain, Nevada, located within this flow system, is being evaluated by the US Department of Energy to determine its suitability as a potential site for a high-level nuclear-waste repository. To assist the US Department of Energy with its evaluation of the Yucca Mountain site, the US Geological Survey developed a parameter… more
Date: December 1, 1990
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effects of Elevated Atmospheric CO{sub 2} on Canopy Transpiration in Senescent Spring Wheat

Description: The seasonal course of canopy transpiration and the diurnal courses of latent heat flux of a spring wheat crop were simulated for atmospheric CO{sub 2} concentrations of 370 {micro}mol mol{sup {minus}1} and 550 {micro}mol mol{sup {minus}1}. The hourly weather data, soil parameters and the irrigation and fertilizer treatments of the Free-Air Carbon Dioxide Enrichment wheat experiment in Arizona (1992/93) were used to drive the model. The simulation results were tested against field measurements … more
Date: December 31, 1998
Creator: Grossman, S.; Kimball, B. A.; Hunsaker, D. J. & Long, S. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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