National Library of Energy BETA

Sample records for 2010-2013

  1. 2010 -2013 Strategic Plan

    E-Print Network [OSTI]

    Sin, Peter

    2010 - 2013 Strategic Plan College of Liberal Arts and Sciences DISCOVER. TEACH. ENGAGE. #12;The strategy for these new and challenging times, I initiated a year-long strategic planning process. Paul D'Anieri, Dean Introduction College of Liberal Arts and Sciences Strategic Plan1 #12;College

  2. The Scottish Forestry Strategy: 2010-2013 Implementation Plan & 2009-2010 Progress Report.

    E-Print Network [OSTI]

    The Scottish Forestry Strategy: 2010-2013 Implementation Plan & 2009-2010 Progress Report. Progress Installed capacity of wood energy plant (in megawatt thermal and electrical) FCS 2006 2007 2008 2009 58 MWt Number of non-domestic, wood fuelled energy systems installed FCS 2006 2007 2008 2009 49 91 154 170 1

  3. VTRA 2010 2013 Preventing Oil Spills from Large Ships and Barges in Northern Puget Sound & Strait of Juan de Fuca

    E-Print Network [OSTI]

    van Dorp, Johan René

    VTRA 2010 2013 Preventing Oil Spills from Large Ships and Barges in Northern Puget Sound & Strait Oil Spill Maritime Simulation Incident Data Expert Judgment & Accident Data Oil Outflow Model TOTAL 2010 TRAFFIC DENSITY 75.2% - NON Focus Vessel 17.0% - CARGO Focus Vessel 7.8% - OIL Focus Vessel + 100

  4. 2033 Long Range Transportation Plan and FY 2010-2013 Transportation Improvement Program 

    E-Print Network [OSTI]

    The West-Memphis Metropolitan Planning Organization

    2009-01-01

    D i t c h N o 1 3 D i t c h N o 2 0 Dit ch # 2 D i t c h N o 1 5 D i t c h N o 1 3 D i t c h N o 9 ? 1 inch = 10,000 feet 2033 WMATS LONG RANGE TRANSPORTATION PLAN Legend LRP WMATS Boundary LRP Pro Principal Arterial LRP Pro Minor...: Marion 2.23% after 2009 West Memphis 0.23% after 2009 Employment 40% in 2006 41% thereafter WMATS ESTIMATED POPULATION AND EMPLOYMENT PROJECTIONS Year Marion Crittenden County Employment A R 7 7 H w y A R 1 4 7 H w y I 5 5 S e r v i c e R d...

  5. Representative Publications with Undergraduate Participants from MCIN Laboratories 2010-2013 (undergraduate authors highlighted in yellow)

    E-Print Network [OSTI]

    stimulates feeding behavior and positive energy balance in a sciurid hibernator. Horm. Behavior. 59, 512 in mammalian hibernators. In: Ruf T, Bieber C, Arnold W, Millesi E, (Eds). Living in a Seasonal World

  6. ‘Mild Mannered’? Protest and Mobilisation in Portugal under Austerity, 2010–2013

    E-Print Network [OSTI]

    Accornero, Guya; Ramos Pinto, Pedro

    2014-08-04

    2013, Kousis and Karakioulafi 2013). In Spain, the Indignados movements, especially the platform ¡Democracia Real YA! (DRY - Real Democracy NOW!) has come to represent a ‘model’ for anti-austerity movements.  5     Using Twitter and Facebook... offshoots of global networks such as Indignados Lisboa, Acampada Lisboa – Democracia Veradeira Já, Portugal Uncut, or ATTAC Portugal - to create the 15-O Platform, coordinating with similar organisations across the world to stage the international...

  7. Prime Minister Julia Gillard Prime Minister of Australia (2010-2013)

    E-Print Network [OSTI]

    Huang, Jianyu

    education, creating an emissions trading scheme, improving the provision and sustainability of health care

  8. Liquid Lithium Divertor and Scrape-Off-Layer Interactions on the National Spherical Torus Experiment: 2010 ? 2013 Progress Report

    SciTech Connect (OSTI)

    None

    2013-08-27

    The implementation of the liquid Lithium Divertor (LLD) in NSTX presented a unique opportunity in plasma-material interactions studies. A high density Langmuir Probe (HDLP) array utilizing a dense pack of triple Langmuir probes was built at PPPL and the electronics designed and built by UIUC. It was shown that the HDLP array could be used to characterize the modification of the EEDF during lithium experiments on NSTX as well as characterize the transient particle loads during lithium experiments as a means to study ELMs. With NSTX being upgraded and a new divertor being installed, the HDLP array will not be used in NSTX-U. However UIUC is currently helping to develop two new systems for depositing lithium into NSTX-U, a Liquid Lithium Pellet Dripper (LLPD) for use with the granular injector for ELM mitigation and control studies as well as an Upward-Facing Lithium Evaporator (U-LITER) based on a flash evaporation system using an electron beam. Currently UIUC has Daniel Andruczyk Stationed at PPPL and is developing these systems as well as being involved in preparing the Materials Analysis Particle Probe (MAPP) for use in LTX and NSTX-U. To date the MAPP preparations have been completed. New sample holders were designed by UIUC?s Research Engineer at PPPL and manufactured at PPPL and installed. MAPP is currently being used on LTX to do calibration and initial studies. The LLPD has demonstrated that it can produce pellets. There is still some adjustments needed to control the frequency and particle size. Equipment for the U-LITER has arrived and initial test are being made of the electron beam and design of the U-LITER in progress. It is expected to have these ready for the first run campaign of NSTX-U.

  9. TX, RRC District 7C Shale Gas Proved Reserves, Reserves Changes...

    Gasoline and Diesel Fuel Update (EIA)

    2010 2011 2012 2013 View History Proved Reserves as of Dec. 31 13 27 81 409 2010-2013 Adjustments 0 -1 1 -1 2010-2013 Revision Increases 0 13 20 217 2010-2013 Revision Decreases 0...

  10. Gonadotropin Inhibitory Hormone: New Insights into the Neuroendocrinology of Stress and Social Conditions

    E-Print Network [OSTI]

    Calisi, Rebecca Marie

    2010-01-01

    Encyclopedia of Animal Behavior. SELECTED GRANTS & AWARDS 2010-2013 National Science Foundation: Postdoc Research Fellowship in Biology

  11. TX, RRC District 2 Onshore Shale Gas Proved Reserves, Reserves...

    Gasoline and Diesel Fuel Update (EIA)

    2010 2011 2012 2013 View History Proved Reserves as of Dec. 31 395 1,692 4,743 5,595 2010-2013 Adjustments 6 237 494 40 2010-2013 Revision Increases 6 388 326 839 2010-2013...

  12. Advanced Biofuels from Cellulose via Genetic Engineering of Clostridiu...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    kg from 2010-2013. By eliminating the aeration step, anaerobic pathway has less CapEx comparing to aerobic pathway (compressor, small reactor, mass transfer). Isoprene...

  13. Basic Quality Design Standards Rating Scale for Single-case Design 

    E-Print Network [OSTI]

    Boles, Margot

    2015-04-08

    This table is a rating scale for the basic design standards for single-case research adapted from Kratochwill et al.(2010; 2013); and Maggin, Briesch, & Chafouleas (2013).

  14. Postdoctoral Research Associate Center for Nanophase Materials Sciences

    E-Print Network [OSTI]

    Pennycook, Steve

    Ridge National Laboratory, USA 2010 - 2013 Postdoctoral Researcher in National Renewable Energy National Laboratory huangb@ornl.gov Publications Education Tsinghua University Physics Ph.D., 2010 Jilin Laboratory, USA Honors 2012 National Excellent Doctoral Dissertation Award (nomination) 2011 Beijing

  15. Smart Grid at EKZ Michael Koller, March 3rd 2015

    E-Print Network [OSTI]

    Daraio, Chiara

    Smart Grid at EKZ Michael Koller, March 3rd 2015 #12;§ 2007 ­ 2010 BSc Chemistry ETH § 2010 ­ 2013 Container Transformer Coupling Transformer 7 #12;EKZ's Smart Grid Lab Michael Koller, EKZ / MEST Info 2015 EKZ Smart Grid Lab Battery Storage Demand Side Management Real time PV power predictions Grid

  16. EA-2003: Sandy River Delta Section 536 Ecosystem Restoration Project, Multnomah County, Oregon

    Broader source: Energy.gov [DOE]

    The U.S. Army Corps of Engineers, with DOE’s Bonneville Power Administration as a cooperating agency, prepared an EA that assessed the potential environmental impacts of the proposed removal of a dam from the east channel of the Sandy River. The proposal would help fulfill a portion of the 2010-2013 Federal Columbia River Power System Biological Opinion Implementation Plan to improve estuary habitat for salmon and steelhead species listed under the Endangered Species Act.

  17. CMS physics highlights in the LHC Run 1

    E-Print Network [OSTI]

    David d'Enterria for the CMS Collaboration

    2015-05-18

    The main physics results obtained by the CMS experiment during the first three years of operation of the CERN Large Hadron Collider (2010--2013, aka. Run 1) are summarized. The advances in our understanding of the fundamental particles and their interactions are succinctly reviewed under the following physics topics: (i) Quantum Chromodynamics, (ii) Quark Gluon Plasma, (iii) Electroweak interaction, (iv) Top quark, (v) Higgs boson, (vi) Flavour, (vii) Supersymmetry, (viii) Dark Matter, and (ix) other searches of physics beyond the Standard Model.

  18. Optical and Radio Variability of BL Lacertae

    E-Print Network [OSTI]

    Gaur, Haritma; Bachev, R; Strigachev, A; Semkov, E; Wiita, Paul J; Volvach, A E; Gu, Minfeng; Agarwal, A; Agudo, I; Aller, M F; Aller, H D; Kurtanidze, O M; Kurtanidze, S O; Lahteenmaki, A; Peneva, S; Nikolashvili, M G; Sigua, L A; Tornikoski, M; Volvach, L N

    2015-01-01

    We observed the prototype blazar, BL Lacertae, extensively in optical and radio bands during an active phase in the period 2010--2013 when the source showed several prominent outbursts. We searched for possible correlations and time lags between the optical and radio band flux variations using multifrequency data to learn about the mechanisms producing variability. During an active phase of BL Lacertae, we searched for possible correlations and time lags between multifrequency light curves of several optical and radio bands. We tried to estimate any possible variability timescales and inter-band lags in these bands. We performed optical observations in B, V, R and I bands from seven telescopes in Bulgaria, Georgia, Greece and India and obtained radio data at 36.8, 22.2, 14.5, 8 and 4.8 GHz frequencies from three telescopes in Ukraine, Finland and USA. Significant cross-correlations between optical and radio bands are found in our observations with a delay of cm-fluxes with respect to optical ones of ~250 days...

  19. Type II and Type III Radio Bursts and their Correlation with Solar Energetic Proton Events

    E-Print Network [OSTI]

    Winter, L M

    2015-01-01

    Using the Wind/WAVES radio observations from 2010-2013, we present an analysis of the 123 decametric-hectometric (DH) type II solar radio bursts during this period, the associated type III burst properties, and their correlation with solar energetic proton (SEP) properties determined from analysis of the Geostationary Operational Environmental Satellite (GOES) observations. We present a useful catalog of the type II burst, type III burst, Langmuir wave, and proton flux properties for these 123 events, which we employ to develop a statistical relationship between the radio properties and peak proton flux that can be used to forecast SEP events. We find that all SEP events with a peak > 10 MeV flux above 15 pfu are associated with a type II burst and virtually all SEP events, 92%, are also associated with a type III radio burst. Based on a principal component analysis, the radio burst properties that are most highly correlated with the occurrence of gradual SEP events and account for the most variance in the ra...

  20. Energy Impact Illinois - Final Technical Report

    SciTech Connect (OSTI)

    Olson, Daniel; Plagman, Emily; Silberhorn, Joey-Lin

    2014-02-18

    Energy Impact Illinois (EI2) is an alliance of government organizations, nonprofits, and regional utility companies led by the Chicago Metropolitan Agency for Planning (CMAP) that is dedicated to helping communities in the Chicago metropolitan area become more energy efficient. Originally organized as the Chicago Region Retrofit Ramp-Up (CR3), EI2 became part of the nationwide Better Buildings Neighborhood Program (BBNP) in May 2010 after receiving a $25 million award from the U.S. Department of Energy (DOE) authorized through the American Recovery and Reinvestment Act of 2009 (ARRA). The program’s primary goal was to fund initiatives that mitigate barriers to energy efficiency retrofitting activities across residential, multifamily, and commercial building sectors in the seven-county CMAP region and to help to build a sustainable energy efficiency marketplace. The EI2 Final Technical Report provides a detailed review of the strategies, implementation methods, challenges, lessons learned, and final results of the EI2 program during the initial grant period from 2010-2013. During the program period, EI2 successfully increased direct retrofit activity in the region and was able to make a broader impact on the energy efficiency market in the Chicago region. As the period of performance for the initial grant comes to an end, EI2’s legacy raises the bar for the region in terms of helping homeowners and building owners to take action on the continually complex issue of energy efficiency.

  1. The secret lives of Cepheids: evolutionary changes and pulsation-induced shock heating in the prototype classical Cepheid ? Cep

    SciTech Connect (OSTI)

    Engle, Scott G.; Guinan, Edward F. [Department of Astrophysics and Planetary Science, Villanova University, Villanova, PA 19085 (United States); Harper, Graham M. [School of Physics, Trinity College Dublin, College Green, Dublin 2 (Ireland); Neilson, Hilding R. [Department of Physics and Astronomy, East Tennessee State University, Box 70652, Johnson City, TN 37614 (United States); Evans, Nancy Remage, E-mail: scott.engle@villanova.edu [Smithsonian Astrophysical Observatory, MS 4, 60 Garden Street, Cambridge, MA 02138 (United States)

    2014-10-10

    Over the past decade, the Secret Lives of Cepheids (SLiC) program has been carried out at Villanova University to study aspects and behaviors of classical Cepheids that are still not well understood. In this, the first of several planned papers on program Cepheids, we report the current results for ? Cep, the Cepheid prototype. Ongoing photometry has been obtained to search for changes in the pulsation period, light-curve morphology, and amplitude. Combining our photometry with the times of maximum light compilation by Berdnikov et al. returns a small period change of dP/dt ?–0.1006 ± 0.0002 s yr{sup -1}. There is also evidence for a gradual light amplitude increase of ?0.011 mag (V band) and ?0.012 mag (B band) per decade over the last ?50 years. In addition, Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) UV spectrophotometry and XMM-Newton X-ray data were carried out to investigate the high-temperature plasmas present above the Cepheid photospheres. In total, from the five visits (eight exposures) with XMM-Newton, ? Cep is found to be a soft X-ray source (L {sub X} (0.3-2 keV) ?4.5-13 × 10{sup 28} erg s{sup -1}) with peak flux at kT = 0.6-0.9 keV. The X-ray activity is found to vary, possibly in phase with the stellar pulsations. From 2010-2013, nine observations of ? Cep were carried out with HST-COS. The UV emissions are also variable and well phased with the stellar pulsations. Maximum UV line emissions occur near, or slightly before, maximum optical light, varying by as much as 20 times. This variability shows that pulsation-induced shock heating plays a significant role in Cepheid atmospheres, possibly in addition to a quiescent, magnetic heating. The results of this study show Cepheid atmospheres to be rather complex and dynamic.

  2. Synthesis and Exploratory Catalysis of 3d Metals: Group-Transfer Reactions, and the Activation and Functionalization of Small Molecules Including Greenhouse Gases

    SciTech Connect (OSTI)

    Mindiola, Daniel J.

    2014-05-07

    Our work over the past three years has resulted in the development of electron rich and low-coordinate vanadium fragments, molecular nitrides of vanadium and parent imide systems of titanium, and the synthesis of phosphorus containing molecules of the 3d transition metal series. Likewise, with financial support from BES Division in DOE (DE-FG02-07ER15893), we now completed the full characterization of the first single molecular magnet (SMM) of Fe(III). We demonstrated that this monomeric form of Fe(III) has an unusual slow relaxation of the magnetization under zero applied field. To make matters more interesting, this system also undergoes a rare example of an intermediate to high-spin transition (an S = 3/2 to S = 5/2 transition). In 2010 we reported the synthesis of the first neutral and low-coordinate vanadium complexes having the terminal nitride functionality. We have now completed a full study to understand formation of the nitride ligand from the metastable azide precursor, and have also explored the reactivity of the nitride ligand in the context of incomplete and complete N-atom transfer. During the 2010-2013 period we also discovered a facile approach to assemble low-coordinate and low-valent vanadium(II) complexes and exploit their multielectron chemistry ranging from 1-3 electrons. Consequently, we can now access 3d ligand frameworks such as cyclo-P3 (and its corresponding radical anion), nitride radical anions and cations, low-coordinate vanadium oxo’s, and the first example of a vanadium thionitrosyl complex. A cis-divacant iron(IV) imido having some ligand centered radical has been also discovered, and we are in the process of elucidating its electronic structure (in particular the sign of zero field splitting and the origin of its magnitude), bonding and reactivity. We have also revisited some paramagnetic and classic metallocene compounds with S >1/2 ground states in order to understand their reactivity patterns and electronic structure. Lastly, we are completing the synthesis and characterization of a titanium nitride anion and formation of the first example of boryl and aluminyl imido titanium complexes.

  3. Multiphase Fluid Flow in Deformable Variable-Aperture Fractures - Final Report

    SciTech Connect (OSTI)

    Detwiler, Russell

    2014-04-30

    Fractures provide flow paths that can potentially lead to fast migration of fluids or contaminants. A number of energy-­?related applications involve fluid injections that significantly perturb both the pressures and chemical composition of subsurface fluids. These perturbations can cause both mechanical deformation and chemical alteration of host rocks with potential for significant changes in permeability. In fractured rock subjected to coupled chemical and mechanical stresses, it can be difficult to predict the sign of permeability changes, let alone the magnitude. This project integrated experimental and computational studies to improve mechanistic understanding of these coupled processes and develop and test predictive models and monitoring techniques. The project involved three major components: (1) study of two-­?phase flow processes involving mass transfer between phases and dissolution of minerals along fracture surfaces (Detwiler et al., 2009; Detwiler, 2010); (2) study of fracture dissolution in fractures subjected to normal stresses using experimental techniques (Ameli, et al., 2013; Elkhoury et al., 2013; Elkhoury et al., 2014) and newly developed computational models (Ameli, et al., 2014); (3) evaluation of electrical resistivity tomography (ERT) as a method to detect and quantify gas leakage through a fractured caprock (Breen et al., 2012; Lochbuhler et al., 2014). The project provided support for one PhD student (Dr. Pasha Ameli; 2009-­?2013) and partially supported a post-­?doctoral scholar (Dr. Jean Elkhoury; 2010-­?2013). In addition, the project provided supplemental funding to support collaboration with Dr. Charles Carrigan at Lawrence Livermore National Laboratory in connection with (3) and supported one MS student (Stephen Breen; 2011-­?2013). Major results from each component of the project include the following: (1) Mineral dissolution in fractures occupied by two fluid phases (e.g., oil-­?water or water-­?CO{sub 2}) causes changes in local capillary forces and redistribution of fluids. These coupled processes enhance channel formation and the potential for development of fast flow paths through fractures. (2) Dissolution in fractures subjected to normal stress can result in behaviors ranging from development of dissolution channels and rapid permeability increases to fracture healing and significant permeability decreases. The timescales associated with advective transport of dissolved ions in the fracture, mineral dissolution rates, and diffusion within the adjacent porous matrix dictate the sign and magnitude of the resulting permeability changes. Furthermore, a high-­? resolution mechanistic model that couples elastic deformation of contacts and aperture-­?dependent dissolution rates predicts the range of observed behaviors reasonably well. (3) ERT has potential as a tool for monitoring gas leakage in deep formations. Using probabilistic inversion methods further enhances the results by providing uncertainty estimates of inverted parameters.

  4. Status Update on the NCRP Scientific Committee SC 5-1 Report: Decision Making for Late-Phase Recovery from Nuclear or Radiological Incidents - 13450

    SciTech Connect (OSTI)

    Chen, S.Y.

    2013-07-01

    In August 2008, the U.S. Department of Homeland Security (DHS) issued its final Protective Action Guide (PAG) for radiological dispersal device (RDD) and improvised nuclear device (IND) incidents. This document specifies protective actions for public health during the early and intermediate phases and cleanup guidance for the late phase of RDD or IND incidents, and it discusses approaches to implementing the necessary actions. However, while the PAG provides specific guidance for the early and intermediate phases, it prescribes no equivalent guidance for the late-phase cleanup actions. Instead, the PAG offers a general description of a complex process using a site-specific optimization approach. This approach does not predetermine cleanup levels but approaches the problem from the factors that would bear on the final agreed-on cleanup levels. Based on this approach, the decision-making process involves multifaceted considerations including public health, the environment, and the economy, as well as socio-political factors. In an effort to fully define the process and approach to be used in optimizing late-phase recovery and site restoration following an RDD or IND incident, DHS has tasked the NCRP with preparing a comprehensive report addressing all aspects of the optimization process. Preparation of the NCRP report is a three-year (2010-2013) project assigned to a scientific committee, the Scientific Committee (SC) 5-1; the report was initially titled, Approach to Optimizing Decision Making for Late- Phase Recovery from Nuclear or Radiological Terrorism Incidents. Members of SC 5-1 represent a broad range of expertise, including homeland security, health physics, risk and decision analysis, economics, environmental remediation and radioactive waste management, and communication. In the wake of the Fukushima nuclear accident of 2011, and guided by a recent process led by the White House through a Principal Level Exercise (PLE), the optimization approach has since been expanded to include off-site contamination from major nuclear power plant accidents as well as other nuclear or radiological incidents. The expanded application under the current guidance has thus led to a broadened scope of the report, which is reflected in its new title, Decision Making for Late-Phase Recovery from Nuclear or Radiological Incidents. The NCRP report, which is due for publication in 2013, will substantiate the current DHS guidance by clarifying and elaborating on the processes required for the development and implementation of procedures for optimizing decision making for late-phase recovery, enabling the establishment of cleanup goals on a site-specific basis. The report will contain a series of topics addressing important issues related to the long-term recovery from nuclear or radiological incidents. Special topics relevant to supporting the optimization of the decision-making process will include cost-benefit analysis, radioactive waste management, risk communication, stakeholder interaction, risk assessment, and decontamination approaches and techniques. The committee also evaluated past nuclear and radiological incidents for their relevance to the report, including the emerging issues associated with the Fukushima nuclear accident. Thus, due to the commonality of the late-phase issues (such as the potential widespread contamination following an event), the majority of the information pertaining to the response in the late-phase decision-making period, including site-specific optimization framework and approach, could be used or adapted for use in case of similar situations that are not due to terrorism, such as those that would be caused by major nuclear facility accidents or radiological incidents. To ensure that the report and the NCRP recommendations are current and relevant to the effective implementation of federal guidance, SC 5-1 has actively coordinated with the agencies of interest and other relevant stakeholders throughout the duration of the project. The resulting report will be an important resource to guide those involved

  5. U.S. NO2 trends (2005–2013): EPA Air Quality System (AQS) data versus improved observations from the Ozone Monitoring Instrument (OMI)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lamsal, Lok N.; Duncan, Bryan N.; Yoshida, Yasuko; Krotkov, Nickolay A.; Pickering, Kenneth E.; Streets, David G.; Lu, Zifeng

    2015-06-01

    Emissions of nitrogen oxides (NOx) and, subsequently, atmospheric levels of nitrogen dioxide (NO2) have decreased over the U.S. due to a combination of environmental policies and technological change. Consequently, NO2 levels have decreased by 30-40% in the last decade. We quantify NO2 trends (2005-2013) over the U.S. using surface measurements from the U.S. Environmental Protection Agency (EPA) Air Quality System (AQS) and an improved tropospheric NO2 vertical column density (VCD) data product from the Ozone Monitoring Instrument (OMI) on the Aura satellite.We demonstrate that the current OMI NO2 algorithm is of sufficient maturity to allow a favorable correspondence of trendsmore »and variations in OMI and AQS data. Our trend model accounts for the non-linear dependence of NO2 concentration on emissions associated with the seasonal variation of the chemical lifetime, including the change in the amplitude of the seasonal cycle associated with the significant change in NOx emissions that occurred over the last decade. The direct relationship between observations and emissions becomes more robust when one accounts for these non-linear dependencies. We improve the OMI NO2 standard retrieval algorithm and, subsequently, the data product by using monthly vertical concentration profiles, a required algorithm input, from a high-resolution chemistry and transport model (CTM) simulation with varying emissions (2005-2013). The impact of neglecting the time-dependence of the profiles leads to errors in trend estimation, particularly in regions where emissions have changed substantially. For example, trends calculated from retrievals based on time-dependent profiles offer 18% more instances of significant trends and up to 15% larger total NO2 reduction versus the results based on profiles for 2005. Using a CTM, we explore the theoretical relation of the trends estimated from NO2 VCDs to those estimated from ground-level concentrations. The model-simulated trends in VCDs strongly correlate with those estimated from surface concentrations (r -- 0.83, N -- 355). We then explore the observed correspondence of trends estimated from OMI and AQS data. We find a significant, but slightly weaker, correspondence (i.e., r -- 0.68, N -- 208) than predicted by the model and discuss some of the important factors affecting the relationship, including known problems (e.g., NOz interferents) associated with the AQS data. This significant correspondence gives confidence in trend and surface concentration estimates from OMI VCDs for locations, such as the majority of the U.S. and globe, that are not covered by surface monitoring networks. Using our improved trend model and our enhanced OMI data product, we find that both OMI and AQS data show substantial downward trends from 2005 to 2013, with an average reduction of 38% for each over the U.S. The annual reduction rates inferred from OMI and AQS measurements are larger (#3;-4.8 ± 1.9%/yr, #3;-3.7 ± 1.5%/yr) from 2005 to 2008 than 2010 to 2013 (-#3;1.2 ± 1.2%/yr, #3;-2.1 ± 1.4%/yr). We quantify NO2 trends for major U.S. cities and power plants; the latter suggest larger negative trend (#3;-4.0 ± 1.5%/yr) between 2005 and 2008 and smaller or insignificant changes (-#3;0.5 ± 1.2%/yr) during 2010-2013.« less

  6. U.S. NO? trends (2005–2013): EPA air quality system (AQS) data versus improved observations from the Ozone Monitoring Instrument (OMI)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lamsal, Lok N.; Duncan, Bryan N.; Yoshida, Yasuko; Krotkov, Nickolay A.; Pickering, Kenneth E.; Streets, David G.; Lu, Zifeng

    2015-06-01

    Emissions of nitrogen oxides (NOx) and, subsequently, atmospheric levels of nitrogen dioxide (NO?) have decreased over the U.S. due to a combination of environmental policies and technological change. Consequently, NO? levels have decreased by 30–40% in the last decade. We quantify NO? trends (2005–2013) over the U.S. using surface measurements from the U.S. Environmental Protection Agency (EPA) Air Quality System (AQS) and an improved tropospheric NO? vertical column density (VCD) data product from the Ozone Monitoring Instrument (OMI) on the Aura satellite.We demonstrate that the current OMI NO? algorithm is of sufficient maturity to allow a favorable correspondence of trendsmore »and variations in OMI and AQS data. Our trend model accounts for the non-linear dependence of NO? concentration on emissions associated with the seasonal variation of the chemical lifetime, including the change in the amplitude of the seasonal cycle associated with the significant change in NOx emissions that occurred over the last decade. The direct relationship between observations and emissions becomes more robust when one accounts for these non-linear dependencies. We improve the OMI NO? standard retrieval algorithm and, subsequently, the data product by using monthly vertical concentration profiles, a required algorithm input, from a high-resolution chemistry and transport model (CTM) simulation with varying emissions (2005-2013). The impact of neglecting the time-dependence of the profiles leads to errors in trend estimation, particularly in regions where emissions have changed substantially. For example, trends calculated from retrievals based on time-dependent profiles offer 18% more instances of significant trends and up to 15% larger total NO? reduction versus the results based on profiles for 2005. Using a CTM, we explore the theoretical relation of the trends estimated from NO? VCDs to those estimated from ground-level concentrations. The model-simulated trends in VCDs strongly correlate with those estimated from surface concentrations (r = 0.83, N = 355). We then explore the observed correspondence of trends estimated from OMI and AQS data. We find a significant, but slightly weaker, correspondence (i.e., r = 0.68, N = 208) than predicted by the model and discuss some of the important factors affecting the relationship, including known problems (e.g., NOz interferents) associated with the AQS data. This significant correspondence gives confidence in trend and surface concentration estimates from OMI VCDs for locations, such as the majority of the U.S. and globe, that are not covered by surface monitoring networks. Using our improved trend model and our enhanced OMI data product, we find that both OMI and AQS data show substantial downward trends from 2005 to 2013, with an average reduction of 38% for each over the U.S. The annual reduction rates inferred from OMI and AQS measurements are larger (–4.8 ± 1.9%/yr, –3.7 ± 1.5%/yr) from 2005 to 2008 than 2010 to 2013 (–1.2 ± 1.2%/yr, –2.1 ± 1.4%/yr). We quantify NO? trends for major U.S. cities and power plants; the latter suggest larger negative trend (–4.0 ± 1.5%/yr) between 2005 and 2008 and smaller or insignificant changes (–0.5 ± 1.2%/yr) during 2010-2013.« less