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Ensemble Single Column Modeling in the Tropics - Derivation of observed forcing data sets, estimation of observation uncertainty and application to parametrization improvements

Description: The project was carried out in 2 distinct phases. In the first phase we established the general validity of using an ensemble approach to Single Column Modeling (SCM) using the Manus and Nauru sites. In the second phase we derived and applied an ensemble forcing derivation technique to observations. First we derived an ensemble forcing estimate for the TWP-ICE experiment and then by extended the method to provide three wet seasons of “continuous ensemble forcing” for the Darwin site. The main purpose of using ensemble techniques in SCM simulation is to be able to assess how much of the overall SCM simulation error is due to model errors and how much due to errors in the forcing.
Date: July 6, 2012
Creator: Jakob, Christian
Partner: UNT Libraries Government Documents Department

Collaborative Proposal: Transforming How Climate System Models are Used: A Global, Multi-Resolution Approach

Description: Despite the great interest in regional modeling for both weather and climate applications, regional modeling is not yet at the stage that it can be used routinely and effectively for climate modeling of the ocean. The overarching goal of this project is to transform how climate models are used by developing and implementing a robust, efficient, and accurate global approach to regional ocean modeling. To achieve this goal, we will use theoretical and computational means to resolve several basic modeling and algorithmic issues. The first task is to develop techniques for transitioning between parameterized and high-fidelity regional ocean models as the discretization grid transitions from coarse to fine regions. The second task is to develop estimates for the error in scientifically relevant quantities of interest that provide a systematic way to automatically determine where refinement is needed in order to obtain accurate simulations of dynamic and tracer transport in regional ocean models. The third task is to develop efficient, accurate, and robust time-stepping schemes for variable spatial resolution discretizations used in regional ocean models of dynamics and tracer transport. The fourth task is to develop frequency-dependent eddy viscosity finite element and discontinuous Galerkin methods and study their performance and effectiveness for simulation of dynamics and tracer transport in regional ocean models. These four projects share common difficulties and will be approach using a common computational and mathematical toolbox. This is a multidisciplinary project involving faculty and postdocs from Colorado State University, Florida State University, and Penn State University along with scientists from Los Alamos National Laboratory. The completion of the tasks listed within the discussion of the four sub-projects will go a long way towards meeting our goal of developing superior regional ocean models that will transform how climate system models are used.
Date: April 15, 2013
Creator: Estep, Donald
Partner: UNT Libraries Government Documents Department

Final Technical Report [Carbon Data Assimilation with a Coupled Ensemble Kalman Filter]

Description: We proposed (and accomplished) the development of an Ensemble Kalman Filter (EnKF) approach for the estimation of surface carbon fluxes as if they were parameters, augmenting the model with them. Our system is quite different from previous approaches, such as carbon flux inversions, 4D-­‐Var, and EnKF with approximate background error covariance (Peters et al., 2008). We showed (using observing system simulation experiments, OSSEs) that these differences lead to a more accurate estimation of the evolving surface carbon fluxes at model grid-­‐scale resolution. The main properties of the LETKF-­‐C are: a) The carbon cycle LETKF is coupled with the simultaneous assimilation of the standard atmospheric variables, so that the ensemble wind transport of the CO2 provides an estimation of the carbon transport uncertainty. b) The use of an assimilation window (6hr) much shorter than the months-­‐long windows used in other methods. This avoids the inevitable “blurring” of the signal that takes place in long windows due to turbulent mixing since the CO2 does not have time to mix before the next window. In this development we introduced new, advanced techniques that have since been adopted by the EnKF community (Kang, 2009, Kang et al., 2011, Kang et al. 2012). These advances include “variable localization” that reduces sampling errors in the estimation of the forecast error covariance, more advanced adaptive multiplicative and additive inflations, and vertical localization based on the time scale of the processes. The main result has been obtained using the LETKF-­‐C with all these advances, and assimilating simulated atmospheric CO2 observations from different observing systems (surface flask observations of CO2 but no surface carbon fluxes observations, total column CO2 from GoSAT/OCO-­‐2, and upper troposphere AIRS retrievals). After a spin-­‐up of about one month, the LETKF-­‐C succeeded in reconstructing the true evolving surface fluxes of carbon at a model grid ...
Date: August 30, 2013
Creator: Kalnay, Eugenia
Partner: UNT Libraries Government Documents Department

Three-Dimensional Imaging and Quantification of Biomass and Biofilms in Porous Media

Description: A new method to resolve biofilms in three dimensions in porous media using high-resolution synchrotron-based x-ray computed microtomography (CMT) has been developed. Imaging biofilms in porous media without disturbing the natural spatial arrangement of the porous media and associated biofilm has been a challenging task, primarily because porous media generally precludes conventional imaging via optical microscopy; x-ray tomography offers a potential alternative. One challenge for using this method is that most conventional x-ray contrast agents are water-soluble and easily diffuse into biofilms. To overcome this problem, silver-coated microspheres were added to the fluid phase to create an x-ray contrast that does not diffuse into the biofilm mass. Using this approach, biofilm imaging in porous media was accomplished with sufficient contrast to differentiate between the biomass- and fluid-filled pore spaces. The method was validated by using a two-dimensional micro-model flow cell where both light microscopy and CMT imaging were used to im age the biofilm. The results of this work has been published in Water Resources Research (Iltis et al., 2010). Additional work needs to be done to optimize this imaging approach, specifically, we find that the quality of the images are highly dependent on the coverage of the biofilm with Ag particles, - which means that we may have issues in dead-end pore space and for very low density (fluffy) biofilms. What we can image for certain with this technique is the biofilm surface that is well-connected to flow paths and thus well-supplied with nutrients etc.
Date: October 10, 2012
Creator: Wildenschild, Dorthe
Partner: UNT Libraries Government Documents Department

ARM Climate Research Facility Quarterly Value-Added Product Report Third Quarter: April 01–June 30, 2011

Description: The purpose of this report is to provide a concise status update for value-added products (VAP) implemented by the Atmospheric Radiation Measurement Climate Research Facility. The report is divided into the following sections: (1) new VAPs for which development has begun, (2) progress on existing VAPs, (3) future VAPs that have been recently approved, (4) other work that leads to a VAP, and (5) top requested VAPs from the archive
Date: August 18, 2011
Creator: Sivaraman, C
Partner: UNT Libraries Government Documents Department

Comparative Genomics and Evolution of Eukaryotic Phospholipid biosynthesis

Description: Phospholipid biosynthetic enzymes produce diverse molecular structures and are often present in multiple forms encoded by different genes. This work utilizes comparative genomics and phylogenetics for exploring the distribution, structure and evolution of phospholipid biosynthetic genes and pathways in 26 eukaryotic genomes. Although the basic structure of the pathways was formed early in eukaryotic evolution, the emerging picture indicates that individual enzyme families followed unique evolutionary courses. For example, choline and ethanolamine kinases and cytidylyltransferases emerged in ancestral eukaryotes, whereas, multiple forms of the corresponding phosphatidyltransferases evolved mainly in a lineage specific manner. Furthermore, several unicellular eukaryotes maintain bacterial-type enzymes and reactions for the synthesis of phosphatidylglycerol and cardiolipin. Also, base-exchange phosphatidylserine synthases are widespread and ancestral enzymes. The multiplicity of phospholipid biosynthetic enzymes has been largely generated by gene expansion in a lineage specific manner. Thus, these observations suggest that phospholipid biosynthesis has been an actively evolving system. Finally, comparative genomic analysis indicates the existence of novel phosphatidyltransferases and provides a candidate for the uncharacterized eukaryotic phosphatidylglycerol phosphate phosphatase.
Date: December 1, 2006
Creator: Lykidis, Athanasios
Partner: UNT Libraries Government Documents Department

Introduction to special section on Hydrologic Synthesis

Description: The Hydrological Synthesis special section presentssynthesis topics that have the potential to revolutionize hydrologicalsciences in a manner needed to meet critical water challenges that we nowface. The special section also highlights topics that are important andexciting enough to compel researchers to engage in collaborativesynthesis activities. This introductory paper provides a brief overviewof nine papers that are included in this special section, which discussthe synthesis of tools, data, concepts, theories, or approaches acrossdisciplines and scales. The wide range of topics that are exploredinclude groundwater quality, river restoration, water management,nitrogen cycling, and Earth surface dynamics. Collectively, the specialsection papers illustrate that the challenge to deal effectively withcomplex water problems is not purely a scientific, technological, orsocioeconomic one; it is instead a complex, 21st century problem thatrequires coordinated synthesis.
Date: January 23, 2006
Creator: Hubbard, Susan
Partner: UNT Libraries Government Documents Department

Final Report

Description: The goal of this project was to quantify organic aerosol precursor concentrations in an urban environment and to measure suitable organic photoproduct species that can act as tracers of photochemical processing to identify the occurrence and rate of secondary organic aerosol formation. Field measurements were made as part of the ASR field program Carbonaceous Aerosols and Radiative Effects Study (CARES) in June 2010. What is new in our approach is the measurement for the total concentration of long chain alkanes (>C10) and heavier alkyl substituted aromatics associated with diesel exhaust gas phase organic compound emissions. A method to measure these so called intermediate volatility organic compounds (IVOCs) was developed by modifying a proton transfer reaction mass spectrometer instrument to perform both volatile organic compound (VOC) and IVOC analysis by thermal desorption from a Tenax adsorbent trap (TD-PTR-MS). Lab and field results show that the TD-PTR-MS technique can measure long chain alkanes associated with diesel engine emissions and thus provide a novel means to measure these compounds to better understand the impact of vehicle emissions on secondary organic aerosol formation.
Date: August 20, 2012
Partner: UNT Libraries Government Documents Department

The NABIR Strategic Plan 2001

Description: For more than 50 years, the U.S. created a vast network of more than 113 facilities for research, development, and testing of nuclear materials. As a result of these activities, subsurface contamination has been identified at over 7,000 discrete sites across the U.S. Department of Energy (DOE) complex. With the end of the Cold War threat, the DOE has shifted its emphasis to remediation, decommissioning, and decontamination of the immense volumes of contaminated groundwater, sediments, and structures at its sites. DOE is currently responsible for remediating 1.7 trillion gallons of contaminated groundwater, an amount equal to approximately four times the daily U.S. water consumption, and 40 million cubic meters of contaminated soil, enough to fill approximately 17 professional sports stadiums. It is estimated that more than 60% of DOE facilities have groundwater contaminated with metals or radionuclides. The only contaminant that appears more often than metal and radionuclide contaminants in groundwater is chlorinated hydrocarbons. More than 50% of all soil and sediments at DOE facilities are contaminated with metal and radionuclides, the contaminants found with the highest frequency in soil at all DOE waste sites. Indeed, while virtually all of the contaminants found at industrial sites nationwide can also be found at DOE sites, many of the metals and especially the radionuclides found on DOE sites are unique to those sites. Current technology for treatment of groundwater contaminated with metals and/or radionuclides is ''pump and treat,'' followed by disposal or reinjection of treated water. This process can be costly and inefficient due to the difficulty of completely removing the contaminated groundwater and sorption of contaminants on mineral surfaces. DOE's Office of Environmental Management (EM), which is responsible for the cleanup, has stated that advances in science and technology are critical for DOE to reduce costs and successfully address these long-term ...
Date: October 22, 2001
Partner: UNT Libraries Government Documents Department

Clinical trials of boron neutron capture therapy [in humans] [at Beth Israel Deaconess Medical Center][at Brookhaven National Laboratory]

Description: Assessment of research records of Boron Neutron Capture Therapy was conducted at Brookhaven National Laboratory and Beth Israel Deaconess Medical Center using the Code of Federal Regulations, FDA Regulations and Good Clinical Practice Guidelines. Clinical data were collected from subjects' research charts, and differences in conduct of studies at both centers were examined. Records maintained at Brookhaven National Laboratory were not in compliance with regulatory standards. Beth Israel's records followed federal regulations. Deficiencies discovered at both sites are discussed in the reports.
Date: May 29, 2001
Creator: Wallace, Christine
Partner: UNT Libraries Government Documents Department

India's pulp and paper industry: Productivity and energy efficiency

Description: Historical estimates of productivity growth in India's pulp and paper sector vary from indicating an improvement to a decline in the sector's productivity. The variance may be traced to the time period of study, source of data for analysis, and type of indices and econometric specifications used for reporting productivity growth. The authors derive both statistical and econometric estimates of productivity growth for this sector. Their results show that productivity declined over the observed period from 1973-74 to 1993-94 by 1.1% p.a. Using a translog specification the econometric analysis reveals that technical progress in India's pulp and paper sector has been biased towards the use of energy and material, while it has been capital and labor saving. The decline in productivity was caused largely by the protection afforded by high tariffs on imported paper products and other policies, which allowed inefficient, small plants to enter the market and flourish. Will these trends continue into the future, particularly where energy use is concerned? The authors examine the current changes in structure and energy efficiency undergoing in the sector. Their analysis shows that with liberalization of the sector, and tighter environmental controls, the industry is moving towards higher efficiency and productivity. However, the analysis also shows that because these improvements are being hampered by significant financial and other barriers the industry might have a long way to go.
Date: July 1, 1999
Creator: Schumacher, Katja
Partner: UNT Libraries Government Documents Department

Global land use data for integrated assessment modeling

Description: Changes in land use and land cover have been one of the major drivers of global change over the last three centuries. Detailed spatially-explicit data sets characterizing these historical land cover changes are now emerging. By synthesizing remotely-sensed land cover classification data sets with historical land use census data, our research group has developed comprehensive databases of historical land use and land cover change. Moreover, we are building estimates of the land suitability for agriculture to predict the constraints on future land use. In this project, we have interacted with the Global Trade and Analysis Project (GTAP) at Purdue University, to adapt our land use data for use with the GTAP database, a baseline database widely used by the integrated assessment modeling community. Moreover, we have developed an interactive website for providing these newly emerging land use data products for the integrated assessment (IA) community and to the climate modeling community.
Date: December 12, 2005
Creator: Ramankutty, Navin
Partner: UNT Libraries Government Documents Department

Atmosphere-Land-Surface Interaction over the Southern Great Plains: Diagnosis of Mechanisms from SGP ARM Data

Description: Work reported included analysis of pentad (5 day) averaged data, proposal of a hypothesis concerning the key role of the Atlantic Multi-decadal Oscillation in 20th century drought and wet periods over the Great Plains, analysis of recurrent super-synoptic evolution of the Great Plains low-level jet, and study of pentad evolution of the 1988 drought and 1993 flood over the Great Plains from a NARR perspective on the atmospheric and terrestrial water balance.
Date: February 1, 2013
Creator: Nigam, Sumant
Partner: UNT Libraries Government Documents Department

Technical Report for DOE grant ER63467-1020269-0008388 ''International Innovation & Diffusion of Environmental Technologies: The Case of NOX''

Description: This research traces the development of nitrogen dioxide (NOX) and sulfur dioxide (SO2) pollution control devices for coal-fired power plants in the United States, Japan, and Germany. This is of particular interest because of the timing of regulation in each country. While the US was an early adopter of SO2 regulations, it did not adopt stringent NOX regulations until the 1990s. Both Japan and Germany adopted stringent NOX regulations earlier. As such, advanced control techniques such as selective catalytic reduction (SCR) were first developed in Japan and Germany. In contrast, US firms were more active in the development of SO2 control devices. This study uses patent data from the three countries, as well as adoption data for individual plants, to trace the development of these technologies. Of particular interest is the role of technology transfer. While we know from previous research that firms respond to new regulations in their own country with new innovations, we do no t know the extent to which firms respond to regulations in foreign countries. Moreover, we know little about how innovations developed abroad enter the domestic knowledge base. For example, do firms make direct use of knowledge developed in foreign countries, or is domestic R&D necessary to adapt these innovations to local conditions. Understanding such trends is important, as it affects both the speed at which technology will diffuse, and the cost of technology transfer. To address these issues, this research compares the role that domestic and foreign knowledge play in the decisions of firms to adopt new environmental technologies. I begin by using patent and regulatory data from the U.S., Japan, and Germany to study the links between both domestic and foreign environmental policy and innovation. I show that innovative activity responds to domestic environmental policy pressures, but not to foreign pressures. Moreover, ...
Date: November 18, 2004
Creator: Popp, David
Partner: UNT Libraries Government Documents Department

Regional-Scale Climate Change: Observations and Model Simulations

Description: This collaborative proposal addressed key issues in understanding the Earth’s climate system, as highlighted by the U.S. Climate Science Program. The research focused on documenting past climatic changes and on assessing future climatic changes based on suites of global and regional climate models. Geographically, our emphasis was on the mountainous regions of the world, with a particular focus on the Neotropics of Central America and the Hawaiian Islands. Mountain regions are zones where large variations in ecosystems occur due to the strong climate zonation forced by the topography. These areas are particularly susceptible to changes in critical ecological thresholds, and we conducted studies of changes in phonological indicators based on various climatic thresholds.
Date: December 14, 2010
Creator: Bradley, Raymond S. & Diaz, Henry F.
Partner: UNT Libraries Government Documents Department


Description: The Cellular and Molecular Fungal Biology Conference provides a forum for presentation of the latest advances in fungal research with an emphasis on filamentous fungi. This open-registration scientific meeting brings together the leading scientists from academia, government and industry to discuss current research results and future directions at Holderness School, an outstanding venue for scientific interaction. A key objective of the conference is to foster interaction among scientists working on model fungi such as Saccharomyces cerevisiae, Schizosaccharomyces pombe, Neurospora crassa and Aspergillus nidulans and scientists working on a variety of filamentous fungi whose laboratory tractability is often inversely proportional to their medical, industrial or ecological importance. Sessions will be devoted to Systems Biology, Fungi and Cellulosic Biomass, Small RNAs, Population Genomics, Symbioses, Pathogenesis, Membrane Trafficking and Polarity, and Cytoskeleton and Motors. A session will also be devoted to hot topics picked from abstracts. The CMFB conference provides a unique opportunity to examine the breadth of fungal biology in a small meeting format that encourages in-depth discussion among the attendees.
Date: June 18, 2010
Creator: Momany, Michelle
Partner: UNT Libraries Government Documents Department

Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds

Description: Project goals: (1) Use the routine surface and airborne measurements at the ARM SGP site, and the routine surface measurements at the NSA site, to continue our evaluations of model aerosol simulations; (2) Determine the degree to which the Raman lidar measurements of water vapor and aerosol scattering and extinction can be used to remotely characterize the aerosol humidification factor; (3) Use the high temporal resolution CARL data to examine how aerosol properties vary near clouds; and (4) Use the high temporal resolution CARL and Atmospheric Emitted Radiance Interferometer (AERI) data to quantify entrainment in optically thin continental cumulus clouds.
Date: September 1, 2011
Creator: Ferrare, Richard A. & Turner, David D.
Partner: UNT Libraries Government Documents Department

Environmental Shortcourse Final report [Joint US-EC Short Course on Environmental Biotechnology: Microbial Catalysts for the Environment]

Description: The Joint US-EC Short Course on Environmental Biotechnology is designed for several purposes. One of the central tenets is to bring together young scientists (at the late Ph.D. or early postdoctoral stages of their careers) in a forum that will set the groundwork for future overseas collaborative interactions. The course is also designed to give the scientists hands-on experience in modern, up-to-date biotechnological methods for the analysis of microbes and their activities pertinent to the remediation of pollutants in the environment. The 2011 course covered multiple theoretical and practical topics in environmental biotechnology. The practical part was centered around a full concise experiment to demonstrate the possibility for targeted remediation of contaminated soil. Experiments included chemical, microbiological, and molecular analyses of sediments and/or waters, contaminant bioavailability assessment, seeded bioremediation, gene probing, PCR amplification, microbial community analysis based on 16S rRNA gene diversity, and microarray analyses. Each of these topics is explained in detail. The practical part of the course was complemented with two lectures per day, given by distinguished scientists from the US and from Europe, covering a research area related to what the students are doing in the course.
Date: March 5, 2013
Creator: Zylstra, Gerben & van der Meer, Jan Roelof
Partner: UNT Libraries Government Documents Department

Entropy-Bayesian Inversion of Time-Lapse Tomographic GPR data for Monitoring Dielectric Permittivity and Soil Moisture Variations

Description: In this study, we evaluate the possibility of monitoring soil moisture variation using tomographic ground penetrating radar travel time data through Bayesian inversion, which is integrated with entropy memory function and pilot point concepts, as well as efficient sampling approaches. It is critical to accurately estimate soil moisture content and variations in vadose zone studies. Many studies have illustrated the promise and value of GPR tomographic data for estimating soil moisture and associated changes, however, challenges still exist in the inversion of GPR tomographic data in a manner that quantifies input and predictive uncertainty, incorporates multiple data types, handles non-uniqueness and nonlinearity, and honors time-lapse tomograms collected in a series. To address these challenges, we develop a minimum relative entropy (MRE)-Bayesian based inverse modeling framework that non-subjectively defines prior probabilities, incorporates information from multiple sources, and quantifies uncertainty. The framework enables us to estimate dielectric permittivity at pilot point locations distributed within the tomogram, as well as the spatial correlation range. In the inversion framework, MRE is first used to derive prior probability distribution functions (pdfs) of dielectric permittivity based on prior information obtained from a straight-ray GPR inversion. The probability distributions are then sampled using a Quasi-Monte Carlo (QMC) approach, and the sample sets provide inputs to a sequential Gaussian simulation (SGSim) algorithm that constructs a highly resolved permittivity/velocity field for evaluation with a curved-ray GPR forward model. The likelihood functions are computed as a function of misfits, and posterior pdfs are constructed using a Gaussian kernel. Inversion of subsequent time-lapse datasets combines the Bayesian estimates from the previous inversion (as a memory function) with new data. The memory function and pilot point design takes advantage of the spatial-temporal correlation of the state variables. We first apply the inversion framework to a static synthetic example and then to a ...
Date: February 12, 2013
Creator: Hou, Z; Terry, N; Hubbard, S S & Csatho, B
Partner: UNT Libraries Government Documents Department

Conference on Nuclear Energy and Science for the 21st Century: Atoms for Peace Plus Fifty - Washington, D.C., October 2003

Description: This conference's focus was the peaceful uses of the atom and their implications for nuclear science, energy security, nuclear medicine and national security. The conference also provided the setting for the presentation of the prestigious Enrico Fermi Prize, a Presidential Award which recognizes the contributions of distinguished members of the scientific community for a lifetime of exceptional achievement in the science and technology of nuclear, atomic, molecular, and particle interactions and effects. An impressive group of distinguished speakers addressed various issues that included: the impact and legacy of the Eisenhower Administration’s “Atoms for Peace” concept, the current and future role of nuclear power as an energy source, the challenges of controlling and accounting for existing fissile material, and the horizons of discovery for particle or high-energy physics. The basic goal of the conference was to examine what has been accomplished over the past fifty years as well as to peer into the future to gain insights into what may occur in the fields of nuclear energy, nuclear science, nuclear medicine, and the control of nuclear materials.
Date: October 22, 2006
Creator: Pfaltzgraff, Robert L
Partner: UNT Libraries Government Documents Department

Collaborative Research: The Influence of Cloud Microphysics and Radiation on the Response of Water Vapor and Clouds to Climate Change

Description: Uncertainties in representing the atmospheric water cycle are major obstacles to an accurate prediction of future climate. This project focused on addressing some of these uncertainties by implementing new physics for convection and radiation into the NCAR climate model. To better understand and eventually better represent these processes, we modified CAM3.5 to use the convection and cloud schemes developed by the Massachusetts Institute of Technology (MIT) and the RRTMG rapid radiation code for global models developed by Atmospheric and Environmental Research, Inc. (AER). The impact of the new physics on the CAM3.5 simulation of convection on diurnal and intra-seasonal scales, intra-seasonal oscillations and the distribution of water vapor has been investigated. The effect of the MIT and AER physics also has been tested in the Weather Research and Forecasting (WRF) regional forecast model. It has been found that the application of the AER radiation and MIT convection produces significant improvements in the modeled diurnal cycle of convection, especially over land, in the NCAR climate model. However, both the standard CAM3.5 (hereinafter STD) and the modified CAM3.5 with the new physics (hereinafter MOD) are still unable to capture the proper spectrum and propagating characteristics of the intra-seasonal oscillations (ISOs). The new physics methods modify, but do not substantially improve, the distribution of upper tropospheric water vapor relative to satellite measurements.
Date: June 28, 2011
Creator: Emanuel, Dr. Kerry & Iacono, Michael J.
Partner: UNT Libraries Government Documents Department