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Recent EES Division HighlightsJune 30, 2008 Low-Level Atmospheric Jets Douglas ReVelle (EES-2) and collaborator E. D. Nilsson (Stockholm University) conducted research on low-level atmospheric jets that form in the Earth's atmospheric planetary boundary layer. The researchers' modeling showed that the low-level jets are ubiquitous. The jets can occur all over the globe from quite windy middle and low latitude and quite rough continental locations to the much smoother Arctic and Antarctic oceanic ice-covered regions in the summertime during periods with much lighter wind speeds. This research demonstrates that atmospheric turbulence could be readily maintained over much smoother lower boundaries and at much lower wind speeds (geostrophic winds) than had ever been appreciated before. (Geostrophic winds occur above the friction layer and develop in response to gradients in atmospheric pressure over large regions of the surface of the earth.) This research was published in "Summertime Low-Level Jets over the High-Latitude Arctic Ocean" in the Journal of Applied Meteorology and Climatology 47, 1770-1784 (2008). The success of this analytic model relies on the fact that the predicted turbulence levels over smoother surfaces in the presence of light winds can be approximately three times greater than those over continental locations with rougher lower boundaries and higher reference wind speeds. These turbulence levels are only available in a very shallow layer (< 5 m in vertical thickness) near the earth's surface, whereas somewhat lower turbulence levels are predicted to extend over a much deeper atmosphere layer (hundreds of meters in vertical thickness) in the middle latitudes. These latter conclusions are based upon predictions of the atmospheric surface boundary layer height that the researchers elaborated upon in a recent addendum that was written since the original paper was accepted in Journal of Applied Meteorology and Climatology. June 18, 2008 Earthquakes in New Mexico?! Yes! In fact, there are several dozen per year recorded in New Mexico, but most are very small (magnitude less than 2.0). On June 4th, around 8:03 AM, however, a magnitude 3.7 earthquake occurred about near Cebolla, about 70 km north of Los Alamos. Folks (including some LANL employees) living in Abiquiu, Tierra Amarilla, Los Alamos, the San Juan Pueblo and Vallecitos felt it; some even had stuff shaken off shelves and reported nervous chickens, etc. The seismic signals overloaded all of the sensors in the Los Alamos Seismic Network (LASN). If you felt it, please go and report it on the USGS website. A full report on this earthquake can also be found on the USGS website. This is the largest of 3 earthquakes recorded in the Cebolla area over the last two weeks. A smaller magnitude 1.6 was recorded on May 31 by LASN, but was not reported by the USGS. A magnitude 2.1 occurred on June 11 and was reported by the USGS. These three earthquakes were roughly 10 km deep as estimated from LASN recordings. They originate from a poorly understood active fault system in the region north of Abiquiu that includes the southern San Juan Mountains. These faults are probably not directly linked with the Rio Grande Rift (further to the east) or to the Jemez Mountains and seismically active Pajarito Fault system near Los Alamos (much further south). Nonetheless, it is noteworthy that the June 4 event was felt in Los Alamos. Fortuitously, a new USArray seismic station near Ortiz Mountain in the Caja del Rio, across the Rio Grande from White Rock, was in place. USArray is a continent-scale seismic observatory experiment run by EarthScope and the LASN benefits from Earthscope data. Members of LANL's Geophysics Group have run LASN continuously since the fall of 1973. The network originally was established as part of LANL's nuclear test ban treaty verification capability. It now is used by engineers and earth scientists for LANL's seismic hazards program. Back in the 1970s, the LASN ran more than 20 stations; now 7 stations are operated. The Infrastructure Support (IS) Program supports the LASN, and required per DOE Order 420.1B. 
(Click thumbnail to view larger image.) June 9, 2008 NNSA and DOE Visit Yucca Mountain On May 29, Brian Dozier (EES-7) conducted a tour of Yucca Mountain for Jeffrey Kupfer, Acting Deputy Secretary of Energy and Chief of Staff, and Thomas D'Agostino, Administrator, National Nuclear Security Administration, as well as several members of their staff. The tour included a general briefing of the tunnel/repository layout and experiments (both completed and ongoing), discussion of the scientific data collected to date, the upcoming submittal of the license application, and general issues about Yucca Mountain. The briefings are conducted in an alcove, an underground excavation off the main tunnel. This alcove has been customized for tours including maps/displays and is about 160 meters (175 yards) underground. Near the conclusion of the visit, Thomas D'Agostino noted that he will be able to use the information when he visits nuclear power plants. On return to the helicopter, the group was met by Steve Mellington, acting NNSA Nevada Site office manager. They then departed for the NTS. June 2, 2008 DOE Submits Yucca Mountain License Application On June 3, 2008 the Department of Energy submitted a license application (LA) to the Nuclear Regulatory Commission (NRC) for consideration of Yucca Mountain, Nevada as the site of the Nation's first permanent repository for spent nuclear fuel and high-level radioactive waste. If a license to construct is granted, the site would become the final disposal site for spent nuclear fuel from the Nation's civilian nuclear power plants as well as the repository for high-level radioactive waste from the Nation's defense activities including nuclear propulsion for the Navy and the atomic weapons program. The 8,600 page LA is the most significant milestone in the nearly three-decade history of the Yucca Mountain Project and sets into motion a regulatory process in which the Nation will make its final determination of whether to use geologic disposal at Yucca Mountain as the solution to its high-level nuclear waste issue. Many believe that this step is necessary for the continued and expanded role of nuclear power as a sustainable energy source to address the nation's need for clean, abundant, and affordable energy 
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For 25 years LANL has made important contributions to the program starting with site selection and characterization and continuing through the recent preparation of the LA. LANL scientists have been instrumental in characterizing the subsurface geology, mineralogy, hydrology, and geochemistry of the site for the purpose of evaluating the ability of the geologic units to reduce mobility of radionuclides should they be released from the engineered repository. LANL staff, in collaboration with scientists and engineers at SNL, LBNL, LLNL, and other institutions, conducted the basic scientific field investigations and laboratory studies and constructed numerical models of water flow and radionuclide transport through the natural system. LANL also played a lead role in the assessment of the probability and potential consequences of future volcanic activity on the repository's ability to isolate radioactive waste. For 20 years, the LANL-led Test Coordination Office (TCO, currently headed up by Doug Weaver, EES-7) also assisted project scientists by coordinating all surface-based and underground tests to ensure that technical objectives, quality assurance, ES&H, and potential impacts to the integrity of a future repository were systematically addressed. The set of scientific activities examining issues relevant to the long-term performance of the repository is integrated into an analysis called the Total System Performance Assessment (TSPA), a probabilistic calculation used to demonstrate compliance with the regulatory standards. The analyses show that the repository meets those standards with a significant margin. 
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The long-term performance assessment is documented in the LA in the form of separate sections focused on the behavior of individual repository components determined to be important to waste isolation, as well as several integrating sections. Of the 18 sections of the LA related to long-term performance, LANL staff were lead authors or co-authors on 5: Climate and Infiltration (Dan Levitt, EES-6), Waste Package and Drip Shield Corrosion (Neil Brown, EES-7), Radionuclide Transport in the Unsaturated Zone (Bruce Robinson, SPO-CNP), Saturated Zone Flow and Transport (Ken Rehfeldt, EES-7), and Igneous Activity (Frank Perry, EES-9). These staff were supported by numerous scientists, engineers, technicians, and administrative and quality specialists at LANL and other National Laboratories to produce documents that meet the exacting standards required for the submittal of a license application to the NRC. The roughly 200 underpinning technical documents produced over the many years of the project, many of which were authored, contributed to, or reviewed by LANL staff also met these high standards for technical quality and compliance with QA procedures. 
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In the future, LANL will continue to help the DOE meet its goal of defending the LA by addressing the issues identified by the NRC as requiring additional information. Any scientific studies determined by the DOE and NRC to be needed to buttress the safety case will be conducted, with LANL heading up the investigations in those areas that it has traditionally led. A phased approach to licensing will, in a scenario culminating in waste disposal, consist of the granting of a license to construct the repository after a three year review period, and a final license to receive and possess waste. These stages are currently planned to culminate in the first disposal of waste as early as the year 2020. 
(Click thumbnail to view larger image.) May 27, 2008 EES-6 Scientist Named to Post Claudia Mora named to National Research Council Board and scientific society office Claudia Mora (EES-6) was named a member of the Board of Earth Sciences and Resources (BESR) of the National Research Council (NRC) for a three-year appointment. The NRC functions under the auspices of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The BESR coordinates the National Research Council's activities on solid-earth science issues and organizes and oversees studies of important national issues in the earth sciences. Claudia Mora was elected Councilor of the Geological Society of America (GSA), a professional society with over 21,500 members in 85 countries. The GSA's mission is "to be a leader in advancing the geosciences, enhancing the professional growth of it members, and promoting the geosciences in the service of humankind." The Council is responsible for managing the affairs and property of the Society including its publications, awards, annual meeting, committee structure and oversight of its corporate business. Mora's term will run from July 2008 -June 2012. May 19, 2008 Effect of Soot and Air Pollution on Arctic Warming The Arctic has warmed twice as fast as the global mean in the last century, and the anthropogenic greenhouse gas forcing accounts for only half of the observed Arctic warming. The Arctic vortex serves as an atmospheric receptor of air pollution from northern midlatitude continental areas as manifested by the thick aerosol layers. This Arctic haze is a regular regional winter and springtime feature. Emission sources that contribute to the haze include anthropogenic black carbon (soot) and sulfate, smoke from massive forest fires, and dust from desert regions. These regional haze perturbations trigger unique regional responses such the darkening of ice from soot deposition which warms the ice and promotes the melting of ice sheets. There are substantial uncertainties in our ability to quantify and predict these regional Arctic forcing and impacts, and the ice is melting faster than computer models predict. Scientists speculate that an ice-free Arctic could raise sea levels and speed global warming because the white ice historically has reflected sunlight back into space rather than absorbing it. Ocean water is much darker and absorbs sunlight. This would abruptly tip the Earth to a new climate state with extreme impacts. 
In April, about 275 scientists from DOE, NASA, NOAA, and Europe converged in northern Alaska with six research aircraft to comprehensively measure the polar environment: radiation, chemistry, aerosols, clouds and ice. Airborne measurements were complemented by space-based measurements from the NASA A Train satellite sensors. Manvendra Dubey (EES-6) and Claudio Mazzoleni (ISR-2) deployed the world's first 3-laser photoacoustic instrument on a Canadian Convair-580 aircraft to measure Arctic pollution. The LANL instrument measures aerosol absorption and scattering at 405, 532 and 781 nm in situ for DOE's Indirect and Semi-direct Effects of Aerosols (ISDAC) campaign.  Manvendra Dubey with the aircraft that carries the photoacoustic instrument. The graph below shows measured pollution over northern Alaska as a function of altitude (aerosol scattering vs. decreasing pressure, or increasing altitude from surface to ~8km). Several haze layers occur between 2-8 km and comprise pollution imported from Siberian forest fires, Eurasian energy production, and Chinese dust, which travel thousands of miles to reach the Arctic. These new data are used to estimate the regional climate forcing by dust, which can be very large if such pollution persists and could be playing a role in the accelerated melting of Arctic ice. The climate forcing warming in this area is 30-40 W/m2, compared with the average of 2-3 W/m2 for the Earth's surface. Unlike global warming from carbon dioxide, which has an atmospheric lifetime of 50 - 100 years, soot has a lifetime of 1-2 weeks. Thus soot is one of the few climate-forcing agents that could be changed rapidly. 
Dubey is invited to present the ISADC findings on behalf of the DOE team at a meeting to discuss "Advances in Modeling and Observing Clouds and Convection" in Meteo-France, Toulouse, France. This is part of the Global Energy and Water Cycle Experiment Cloud System Study that investigates cloud systems, their role in the climate system and their representation in models with a view to improving the capability to predict weather and climate using state-of the-art modeling and data assimilation systems. The DOE Office of Science, Atmospheric Science Program supported LANL's fieldwork in the Arctic. An LDRD DR supported the instrumentation development. May 2nd, 2008 Presentations at the Seismological Society of America Meeting LANL researchers from EES hosted and presented at the recent SSA meeting in Santa Fe. Jamie Gardner (EES-9) gave an invited talk at the special session "Extensional Seismotectonics of the Rio Grande Rift and its Margins". The talk, "Paleoseismology and Geology of the Pajarito Fault System, Rio Grande Rift, New Mexico," provided a synthesis of results from about 20 years of research regarding seismic hazards at LANL. The Pajarito Fault System which forms the western boundary of LANL presents a potentially serious earthquake hazard to the Laboratory. Co-authors on the EES Seismic Geology Team are C. Lewis, S. Reneau, and E. Schultz-Fellenz 
(Click thumbnail to view larger image.) EES-11's Chris Bradley chaired and gave a presentation in a session entitled "Earthquakes and Society: Developing Community Resiliency through Earthquake Scenarios". Chris' talk, "Site-specific Rock Mechanical and Slope Stability Analysis of the BSL-3 Facility" addressed the earthquake response of the new Biological Safety Laboratory (BSL-3) to the newly released Probabilistic Seismic Hazard Analysis (PSHA) for LANL. The study included 3-D numerical modeling of the fractured and jointed Bandelier Tuff to synthetic earthquakes. Coauthors of the study included Tom Houston (D-5), Peter Roberts, and David Steedman (EES-11), and Claudia Lewis (EES-9). April 28, 2008 Volcanic Risk Assessment at Yucca Mountain Gordon Keating, Greg Valentine, Don Krier, and Frank Perry of EES-9 published a paper that quantifies key parameters used to model eruption scenarios for volcanic risk assessment at the planned Yucca Mountain high-level radioactive waste repository in Nevada. "Shallow Plumbing Systems for Small-volume Basaltic Volcanoes" summarizes field work of eroded analogue volcanoes that were used to characterize the geometry of potential future basaltic conduits through the Yucca Mountain repository. The paper compares field measurements to theoretical considerations of conduit flow in order to draw general conclusions about the size and shape of potential conduits at repository depth (ca. 300 m) and the nature of the transition from dike to conduit at shallow depths. Quantification of the size and geometry of basaltic conduits has not been done previously at this depth range. This kind of information is critical in the analysis of consequences of a potential basaltic eruption through the waste repository. Given the explicit layout of storage tunnels and the shape and disposition of waste packages, the size and geometry of a magmatic conduit developing at the repository horizon has direct bearing on the number of waste packages damaged and the amount of waste released during a potential volcanic eruption. The quantification of magma conduit geometry developed in this paper provides direct input to the eruptive case submodel of the Yucca Mountain Total System Performance Assessment (TSPA). In a broader sense, the comparison of field observations to conduit geometries developed in the numerical model supports the concept of lithostatic-pressure balanced flow conditions put forth by Wilson and Head (1981). DOE's Yucca Mountain Project funded the research. 
(Click thumbnail to view larger image.) The paper is published in the Bulletin of Volcanology 70: 563-582 (2008). April 12, 2008 LANL Hosts Annual Meeting of the Seismological Society of America (SSA) The world's leading seismologists gathered in Santa Fe, NM for the 102nd Annual meeting of the SSA. LANL was the host institute for the meeting in cooperation with other Rio Grande institutions including Sandia National Laboratories, New Mexico Tech, and University of Texas at El Paso. Charlotte Rowe of EES-11 chaired the meeting. Approximately 500 national and international scientists attended. This meeting affords EES researchers the opportunity to present their research and participate in stimulating exchanges of the latest research on earthquakes, volcanoes, nuclear explosions, and more. Over 450 abstracts were received. Thirty EES researchers are authors or co-authors on 25 different research presentations. Six EES-11 staff members co-convened five of the special technical sessions...
 Many of the LANL presentations were the result of collaborations with industry, government organizations, and universities. Read more at the SSA web site. April 1, 2008 Multiscale Analysis Applicable to Field Scale Simulations A major problem in modeling natural porous media is obtaining an accurate description of their flow and transport behavior in spite of the intrinsic heterogeneity of geological formations. The modeling equations have coefficients that vary on scales that are small compared with the overall size of the domain of interest. Any accurate numerical solution of these models requires a very finely divided computational mesh, something that often is not feasible. Obtaining the macroscopic behavior of a given system can become computationally expensive even with modern supercomputers. Therefore, to analyze the system from a macrostructure point of view, it is desirable to simplify it in such a way that the phenomena of interest remain adequately described. The simplified equations are called homogenized equations, and the procedure of replacing the original system is called homogenization. Researchers Roseangela Svlercoski and Brayan Travis of EES-2 and T-7's James Hyman recently published a paper entitled "Analytical effective coefficient and a first-order approximation for linear flow through block permeability inclusions" in Computers & Mathematics with Applications, 55 (9), 2118-2133, (2008). These new results are applicable to idealized geometric form of inclusions in a main matrix. However, the extension to the general case is possible and it is ongoing work. The new results will allow multiscale numerical simulations for field scale applications which is also the new feature of the method. (Read more.) The LANL researchers have developed an approach that differs from the previous ones, by simplifying the numerics involved in such approximations. The approach has the enormous advantage of portability because it can be used with any existing elliptic solver. Below, Figure 1 shows a comparison of the analytic solution with square inclusion and the relevant numerical approximation. The two graphs agree well with each other but differ on the smoothness. The ultimate goal is to apply the method to multiphase systems in cases where diffusion is the driving process. A Chevron-LANL CRADA provided support for the work.  Left - Analytical solution with square inclusion. Right - Numerical approximation.
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