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Synthesis, Analysis, and Integration of Meteorological and Air Quality Data for the Gulf of Mexico Region, Volume 4: CART Analysis of Modeling Episode Days

Description: "This report summarizes the combined analysis of photochemical modeling results and Classification and Regression Tree analysis results for selected areas along the Gulf Coast."
Date: December 2009
Creator: Douglas, Sharon G.; Hudischewskyj, A. Belle & Haney, Jay L.
Partner: UNT Libraries Government Documents Department

Three-dimensional elastic lidar winds

Description: Maximum cross-correlation techniques have been used with satellite data to estimate winds and sea surface velocities for several years. Los Alamos National Laboratory (LANL) is currently using a variation of the basic maximum cross-correlation technique, coupled with a deterministic application of a vector median filter, to measure transverse winds as a function of range and altitude from incoherent elastic backscatter lidar data taken throughout large volumes within the atmospheric boundary layer. Hourly representations of three- dimensional wind fields, derived from elastic lidar data taken during an air-quality study performed in a region of complex terrain near Sunland Park, New Mexico, are presented and compared with results from an Environmental Protection Agency (EPA) approved laser doppler velocimeter. The wind fields showed persistent large scale eddies as well as general terrain following winds in the Rio Grande valley.
Date: July 1, 1996
Creator: Buttler, W.T.
Partner: UNT Libraries Government Documents Department

Photodissociation of ozone at 276nm by photofragment imaging and high resolution photofragment translational spectroscopy

Description: The photodissociation of ozone at 276 nm is investigated using both state resolved ion imaging and high-resolution photofragment translational spectroscopy. Ion images from both [3+1] and [2+1] resonance enhanced multiphoton ionization of the O({sup 1}D) photofragment are reported. All images show strong evidence of O({sup 1}D) orbital alignment. Photofragment translation spectroscopy time-of-flight spectra are reported for the O{sub 2} ({sup 1}{Delta}{sub g}) photofragment. Total kinetic energy release distributions determined form these spectra are generally consistent with those distributions determined from imaging data. Observed angular distributions are reported for both detection methods, pointing to some unresolved questions for ozone dissociation in this wavelength region.
Date: November 1, 1996
Creator: Blunt, D.A. & Suits, A.G.
Partner: UNT Libraries Government Documents Department

Carbon Dioxide Analysis Center and World Data Center-A for Atmospheric Trace Gases fiscal year 1997 annual report

Description: Fiscal year (FY) 1997 was another exciting and productive one for the Carbon Dioxide Information Analysis Center (CDIAC) at the Oak Ridge National Laboratory. During FY 1997, CDIAC launched the Quality Systems Science Center for the North American Research Strategy for Tropospheric Ozone (NARSTO). The purpose of NARSTO--a US-Canada-Mexico initiative of government agencies, industry, and the academic research community--is to improve the understanding of the formation and transport of tropospheric ozone.
Date: March 1, 1998
Creator: Burtis, M.D.; Cushman, R.M.; Boden, T.A.; Jones, S.B.; Kaiser, D.P. & Nelson, T.R.
Partner: UNT Libraries Government Documents Department

SAGE II/Umkehr ozone comparisons and aerosols effects: An empirical and theoretical study. Final report

Description: The objectives of this research were to: (1) examine empirically the aerosol effect on Umkehr ozone profiles using SAGE II aerosol and ozone data; (2) examine theoretically the aerosol effect on Umkehr ozone profiles; (3) examine the differences between SAGE II ozone profiles and both old- and new-format Umkehr ozone profiles for ozone-trend information; (4) reexamine SAGE I-Umkehr ozone differences with the most recent version of SAGE I data; and (5) contribute to the SAGE II science team.
Date: September 15, 1997
Creator: Newchurch, M.
Partner: UNT Libraries Government Documents Department

Comparison of CCM3 simulations using two climatological ozone data sets

Description: A comparison of two six year simulations with the CCM3 using different monthly mean, zonally symmetric ozone climatologies is presented. Each run was identical except for the ozone specification. The climatological SSTs supplied with CCM3 were cycled for the extent of the simulation. The ozone data sets were used were the data distributed with the CCM3 code and that compiled at SUNY Albany. The SUNYA data set reflects contemporary ozone measurements extensively using remote sensing data. The CCM3 data were produced from measurements prior to 1974. A brief comparison of the two ozone climatologies is presented. The monthly mean difference fields were computed for the six years of the simulations. A t-test was applied to the monthly mean difference to judge if the changes between the integrations were significant. The significant changes in temperature were for the most part confined to the levels above 200 hPa. In the zonal mean the patterns of differences were largely consistent with regions of the ozone variations, deeper tropospheric penetration of temperature difference occurred in October near the South Pole in the region of the `ozone hole`. The significant temperature changes at the lowest model level (approximately 992 hPa) were confined to very small areas. The 200 hPa zonal wind differences demonstrated that the stationary wave structure was evidently altered by the ozone difference. Although the ozone specifications were zonally symmetric, the zonal wind differences were zonally asymmetric at 200 hPa.
Date: February 1, 1997
Creator: Boyle, J.S.
Partner: UNT Libraries Government Documents Department

Ozonosphere Observations from Propagation of Atomic Blast Waves

Description: Abstract: "Observations of refracted sound waves from atomic tests at the Nevada and Pacific Proving Grounds are evaluated to show temperature and winds in the ozonosphere. A simplified method of making these interpretations is presented to reduce the computation work load normally associated with atmospheric sound studies."
Date: October 1, 1954
Creator: Reed, Jack W.
Partner: UNT Libraries Government Documents Department

Report of the First Session of the WMO/UNEP Intergovernmental Panel on Climate Change (IPCC)

Description: The first session of the Intergovernmental Panel on Climate Change (IPCC) was held in Geneva, Switzerland, from 9 to 11 November 1988. The Intergovernmental Panel of Climate Change (IPCC) is the leading body for the assessment of climate change, established by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) to provide the world with a clear scientific view on the current state of climate change and its potential environmental and socio-economic consequences.
Date: 1989
Creator: Intergovernmental Panel on Climate Change (IPCC)
Partner: UNT Libraries

Experimental determination of the HO-Br bond energy and its relevance to the stratospheric and tropospheric ozone cycles

Description: The HO-Br bond energy (and consequently the heat of formation of HOBr) has been determined experimentally for the first time. HOBr can be photolyzed in the stratosphere to form Br and OH, both of which can react with ozone, and destroy it. Previous calculations modeling stratospheric reactions have assumed a lower stability than that found in the current research. The stability of HOBr was determined by measuring the threshold for formation of Br{sup +} from this molecule, using photoionization mass spectrometry. Their work was supported by the Division of Chemical Sciences, Office of Basic Energy Sciences.
Date: February 1, 1996
Creator: Ruscic, B. & Berkowitz, J.
Partner: UNT Libraries Government Documents Department

Evaluating the importance of innovative heterogeneous chemistry to explain observed stratospheric ozone depletion

Description: Currently, there is a widespread search for additional heterogeneous reactions or combination of heterogeneous and homogeneous (gas-phase) reactions that could catalytically reduce ozone to observed levels. In 1992, Burley and Johnston proposed that nitrosyl sulfuric acid (NSA) NOHSO{sub 4}, is a promising heterogeneous reactant for activating HCl in sulfuric acid particles. They list several sources for producing it in the stratosphere and they carried out thermodynamic and chemical kinetic calculations at one stratospheric altitude and at one latitude. NSA has been overlooked in all previous stratospheric model calculations, even though it has been observed in stratospheric sulfate aerosols. This study makes large scale atmospheric model calculations to test the proposal by Burley and Johnston that a promising heterogeneous process for activating HCl in sulfuric acid particles is a catalytic coupled based on nitrosyl sulfuric acid (NSA). This mechanism is examined under non-volcanic and volcanic conditions representative of the recent eruption of Mt. Pinatubo. The calculations set firm limits on the range of kinetic parameters over which this heterogeneous processes would be important in the global ozone balance, and thus is a guide for where laboratory work is needed. In addition, they have derived a preliminary time-dependent integration (1980--1994) to represent the observed trend in ozone. Comparison between model-derived and the observed ozone trend will be compared.
Date: February 27, 1996
Creator: Kinnison, D. E. & Connell, P. S.
Partner: UNT Libraries Government Documents Department

Investigation of the effect of natural phenomena and industrial activity on stratospheric ozone trends. Final report, September 1993--June 1998

Description: The long term goal of this work is to separate the effects of natural variability and anthropogenic emissions on the chemical composition of the atmosphere. In particular, the authors are concerned with the variability of ozone in the stratosphere and the supply of ozone from the stratosphere to the upper troposphere. During the first phase of this project the authors developed an interactive two-dimensional (2D) model of the dynamics, radiation, and chemistry of the stratosphere. The most important features of the model are the use of the full primitive equations in two dimensions, small horizontal mixing in the tropical regions and small mechanical damping in the lower stratosphere. As a result, transport in the tropics and the mass exchange between the tropics and midlatitude are controlled advectively.
Date: December 1, 1998
Creator: McElroy, M.B. & Schneider, H.R.
Partner: UNT Libraries Government Documents Department

The U.S. Global Change Research Program

Description: The Office of Science and Technology Policy has established the National Science and Technology Council (NSTC) to help solve problems, to improve economic competitiveness, and to provide stimulus for education. Within the NSTC, the Committee on Environment and Natural Resources Research is responsible for seven environmental issues, including all research relating to global change. The US Global Change Research Program supports international protocols and conventions relating to ozone, climate, and biodiversity. It contributes to the advancement of knowledge in science, education, and technology transfer by providing scientific understanding for policy. This program supports the mission of federal agencies in the areas of forecasts, regulations, services, etc.
Date: May 4, 1994
Creator: MacCracken, M.C.
Partner: UNT Libraries Government Documents Department

Guidance on the DOE facility phaseout of ozone-depleting substances

Description: The phaseout of ozone-depleting substances substantially affects Department of Energy (DOE) operations associated with refrigeration and air conditioning, fire protection, and solvent usage throughout the complex. Among the more important requirements facing the Department in this area are those associated with Executive Order 12843 (``Procurement Requirements and Policies for Federal Agencies for Ozone-Depleting Substances``), the Environmental Protection Agency (EPA) regulations that implement (``Federal Procurement``) of the Clean Air Act, and an interim rule (``Federal Acquisition Regulation; Ozone Executive Order``) that amends the Federal Acquisition Regulation (FAR). The first two directives require Federal agencies to significantly reduce use, where practicable, of ozone-depleting substances, through cost-effective procurement practices and through the substitution of safe alternative substances, and to provide leadership in their phaseout.
Date: October 1, 1995
Partner: UNT Libraries Government Documents Department

A technique using a stellar spectrographic plate to measure terrestrial ozone column depth

Description: This thesis examines the feasibility of a technique to extract ozone column depths from photographic stellar spectra in the 5000--7000 Angstrom spectral region. A stellar spectrographic plate is measured to yield the relative intensity distribution of a star`s radiation after transmission through the earth`s atmosphere. The amount of stellar radiation absorbed by the ozone Chappuis band is proportional to the ozone column depth. The measured column depth is within 10% the mean monthly value for latitude 36{degree}N, however the uncertainty is too large to make the measurement useful. This thesis shows that a 10% improvement to the photographic sensitivity uncertainty can decrease the column depth uncertainty to a level acceptable for climatic study use. This technique offers the possibility of measuring past ozone column depths.
Date: August 1, 1995
Creator: Wong, A.Y.
Partner: UNT Libraries Government Documents Department

Atmospheric Science Program. Summaries of research in FY 1994

Description: This report provides descriptions for all projects funded by ESD under annual contracts in FY 1994. Each description contains the project`s title; three-year funding history (in thousands of dollars); the contract period over which the funding applies; the name(s) of the principal investigator(s); the institution(s) conducting the projects; and the project`s objectives, products, approach, and results to date (for most projects older than one year). Project descriptions are categorized within the report according to program areas: atmospheric chemistry, atmospheric dynamics, and support operations. Within these categories, the descriptions are ordered alphabetically by principal investigator. Each program area is preceded by a brief text that defines the program area, states it goals and objectives, lists principal research questions, and identifies program managers. Appendixes provide the addresses and telephone numbers of the principal investigators and define the acronyms used.
Date: June 1, 1995
Partner: UNT Libraries Government Documents Department

Report of the 22nd Session of the IPCC

Description: The session opened after a lighting of lamp ceremony by H.E. Mr Thiru A. Raja, Minister of Environment and Forests, India and other dignitaries. Following this a number of speakers noted the significance of ensuring that the findings of the Fourth Assessment Report (AR4) reach the public at large, and the need for AR4 to highlight research in developing countries. UNEP Executive Director highlighted the significance of the work of the IPCC for related policy processes, and commended the increased involvement by women and developing country authors in the AR4. Mr Halldor Thorgeirsson highlighted the importance placed by the UNFCCC on climate monitoring, the ongoing revision of the greenhouse gas (GHG) reporting guidelines, and good practice guidance on land use, land-use change and forestry.
Date: November 2004
Creator: Intergovernmental Panel on Climate Change (IPCC)
Partner: UNT Libraries

Report of the 23rd Session of the IPCC

Description: In the context of this agenda item discussion took place on the management plan for the AR4 SYR. The Panel agreed that further consideration will be given by the Bureau to aspects of arrangements for management of the AR4 SYR, and progress reported to the Panel.
Date: September 2005
Creator: Intergovernmental Panel on Climate Change (IPCC)
Partner: UNT Libraries

Report of the 24th Session of the IPCC

Description: The meeting highlighted recent progress in the work of the IPCC, in particular the completion of the two Special Reports on Safeguarding the Ozone Layer and the Global Climate System (SROC), and on Carbon Dioxide Capture and Storage (SRCCS) and the preparations for the Fourth Assessment Report (AR4). Among other speakers, the Executive Director of the United Nations Environment Program (UNEP), Mr Klaus Töpfer addressed the Session on the linkages between science and climate change policy and the increasing need for information from the IPCC. He reaffirmed UNEP's commitment to the IPCC and supported early planning for the period beyond AR4. The Deputy Secretary-General of the World Meteorological Organization (WMO), also addressed the Panel on the importance of the principles of impartiality, transparency, scientific authority and integrity for the past success of the IPCC, the linkages of WMO programmes and IPCC assessments, and WMO's commitment to the IPCC.
Date: September 2005
Creator: Intergovernmental Panel on Climate Change (IPCC)
Partner: UNT Libraries

Investigation into environmentally friendly alternative cleaning processes for hybrid microcircuits to replace vapor degreasing with 1,1,1-trichloroethane. Final report

Description: Two cleaning processes, one aqueous and one nonaqueous, were investigated as potential replacements for the vapor degreasing process using 1,1,1 trichloroethane (TCA) for hybrid microcircuit assemblies. The aqueous process was based upon saponification chemistry. A 10% solution of either Kester 5768 or Armakleen 2001, heated to 140 F, was sprayed on the hybrid at 450 psig and a flow rate of 5 gpm through a specially designed nozzle which created microdroplets. The nonaqueous process was based upon dissolution chemistry and used d-limonene as the solvent in an immersion and spray process. The d-limonene solvent was followed by an isopropyl alcohol spray rinse to remove the excess d-limonene. The aqueous microdroplet process was found to be successful only for solder reflow profiles that did not exceed 210 C. Furthermore, removal of component marking was a problem and the spray pressure had to be reduced to 130 psig to eliminate damage to capacitor end caps. The d-limonene cleaning was found to be successful for solder reflow temperature up to 250 C when using a four-step cleaning process. The four steps included refluxing the hybrid at 80 C, followed by soaking the hybrid in d-limonene which is heated to 80 C, followed by spray cleaning at 80 psig with room temperature d-limonene, followed by spray cleaning at 80 psig with room temperature IPA was developed to remove residual flux from the hybrid microcircuits. This process was the most robust and most closely matched the cleaning ability of TCA.
Date: February 1, 1997
Creator: Adams, B.E.
Partner: UNT Libraries Government Documents Department

Materials compatibility issues associated with aqueous alkaline cleaners

Description: As part of the Environmentally Conscious Manufacturing (ECM) technology, and in support of various mechanical assembly applications, several aqueous alkaline cleaners were studied as potential candidates for cleaning mechanical piece parts. Historically, ozone depleting and hazardous chlorinated cleaners have been used to degrease mechanical assemblies. In an effort to replace these chemicals, several cleaning processes, including aqueous alkaline cleaners, were screened as potential candidates using a variety of criteria, including aqueous alkaline cleaners, were screened as potential candidates using a variety of criteria, including: cleaning efficiency, materials compatibility, etch rate, corrosion, immersion tests, temperature/humidity exposure, and an exposure to a simulated indoor industrial environment. Cleaning efficiency was determined using visual examination, Auger electron spectroscopy, X-ray photoelectron spectroscopy, MESERAN, and goniometer/contact angle measurements. Several cleaners were identified as potential alternatives based solely on the cleaning results. Some of the cleaners, however, left undesirable residues. This paper will focus on materials compatibility issues of these aqueous cleaners after immersion tests, an etch rate study, and exposures to temperature/humidity and a standard industrial environment.
Date: April 1, 1996
Creator: Lopez, E.P. & Montoya, M.G.
Partner: UNT Libraries Government Documents Department