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Improved Magnus` form approximation of saturation vapor pressure

Description: Relative humidity is usually measured in aerological observations and dew point depression is usually reported in upper-air reports. These variables must frequently be converted to other moisture variables in meteorological analysis. If relative humidity is converted to vapor pressure, most humidity variables can then be determined. Elliott and Gaffen reviewed the practices and procedures of the US radiosonde system. In their paper, a comparison of the relative errors was made between the saturation vapor pressure formulations of Tetens (1930), Goff-Gratch (1946), Wexler (1976), and Buck (1981). In this paper, the authors will expand the analysis of Elliott and Gaffen by deriving several new saturation vapor pressure formulas, and reviewing the various errors in these formulations. They will show that two of the new formulations of vapor pressure over water and ice are superior to existing formulas. Upper air temperature data are found to vary from about +50 C to {minus}80 C. This large variation requires a saturation vapor pressure equation to be accurate over a large temperature range. While the errors introduced by the use of relatively inaccurate conversion equations are smaller than the errors due to the instruments, dewpoint coding errors, and dewpoint conversion algorithms (Elliott and Gaffen, 1993); they introduce additional systematic errors in humidity data. The most precise formulation of vapor pressure over a plane surface of water was given by Wexler (1976). The relative errors of Tetens` (1930) formula and one due to Buck (1981) (Buck`s equation is recommended in the Federal Meteorological Handbook No. 3, 1991) are shown. The relative errors in this table are the predicted value minus the Wexler value divided by the Wexler value.
Date: November 1997
Creator: Alduchov, O. A. & Eskridge, R. E.
Partner: UNT Libraries Government Documents Department

Aerosol optical depth estimates based on nephelometer measurements at the SGP arm site

Description: The scattering of shortwave radiation by anthropogenic aerosols during clear-sky conditions, termed direct aerosol forcing, has been estimated to be roughly 1 W/m{sup 2} on a global annual average and may be as high as 50 W/m{sup 2} locally and instantaneously new source regions. The extent of the direct aerosol forcing effect at a given time and place depends primarily in the aerosol optical depth, {tau}, as well as on other factors including the solar zenith angle, aerosol upscatter fraction, and the single scatter albedo (ratio of light scattering to total extinction). The aerosol optical depth at a given wavelength ({tau}{sub {lambda}}) can be written as the integral with height to the top of the atmosphere (toa) of the aerosol extinction coefficient, b{sub ext,p}. Where b{sub ext,p} is the sum of the aerosol extinction (b{sub ap}) and scattering (b{sub sp}) coefficients. The objectives of this research are to use nephelometer measurements of the scattering coefficient to estimate the aerosol optical depth at a specific wavelength (530 nm), and to compare these results with optical depths measured by a Multi-Filter Rotating Shadowband Radiometer (MFRSR) and Cimel Sun Photometer. This comparison will used to determine if all of the key parameters related to aerosol optical depth are being measured at the SGP ARM site.
Date: March 1996
Creator: Bergin, M. H.; Ogren, J. A. & Halthore, R.
Partner: UNT Libraries Government Documents Department

The biogeochemistry of carbon in continental slope sediments: The North Carolina margin

Description: The responses of the continental slope benthos to organic detritus deposition were studied with a multiple trace approach. Study sites were offshore of Cape Fear (I) and Cape Hatteras (III), N.C. (both 850 m water depth) and were characterized by different organic C deposition rates, macrofaunal densities (III>I in both cases) and taxa. Natural abundances of {sup 13}C and {sup 12}C in particulate organic carbon (POC), dissolved inorganic carbon (DIC) and macrofauna indicate that the reactive organic detritus is marine in origin. Natural abundance levels of {sup 14}C and uptake of {sup 13}C-labeled diatoms by benthic animals indicate that they incorporate a relatively young component of carbon into their biomass. {sup 13}C-labeled diatoms (Thalassiorsira pseudonana) tagged with {sup 210}Pb, slope sediment tagged with {sup 113}Sn and {sup 228}Th-labeled glass beads were emplaced in plots on the seafloor at both locations and the plots were sampled after 30 min., 1-1.5 d and 14 mo. At Site I, tracer diatom was intercepted at the surface primarily by protozoans and surface-feeding annelids. Little of the diatom C penetrated below 2 cm even after 14 months. Oxidation of organic carbon appeared to be largely aerobic. At Site III, annelids were primarily responsible for the initial uptake of tracer. On the time scale of days, diatom C was transported to a depth of 12 cm and was found in animals collected between 5-10 cm. The hoeing of tracer from the surface by the maldanid Praxillela sp. may have been responsible for some of the rapid nonlocal transport. Oxidation of the diatom organic carbon was evident to at least 10 cm depth. Anaerobic breakdown of organic matter is more important at Site III. Horizontal transport, which was probably biologically mediated, was an order of magnitude more rapid than vertical displacement over a year time scale. If ...
Date: December 1, 1999
Creator: Blair, N.; Levin, L.; DeMaster, D.; Plaia, G.; Martin, C.; Fornes, W. et al.
Partner: UNT Libraries Government Documents Department

Fisheries Ecosystem Model of the Chesapeake Bay: Methodology, Parameterization, and Model Exploration

Description: Report on the construction of a model to manage fisheries in the Chesapeake Bay region, to see how stocks affect the food web and provide quantified estimations. "This report describes an ecosystem model of the Chesapeake Bay, the Chesapeake Bay Fisheries Ecosystem Model (CBFEM), prepared using the Ecopath with Ecosim approach and software" (p. 5).
Date: October 2009
Creator: Christensen, Villy; Beattie, Alasdair; Buchanan, Claire; Ma, Hongguang; Martell, Steven J. D.; Latour, Robert J. et al.
Location Info:
Partner: UNT Libraries Government Documents Department

Abrupt Climate Change

Description: This is an excerpt of a report series produced by the U.S. Climate Change Science Program (CCSP) aimed at providing current assessments of climate change science to inform public debate, policy, and operational decisions. The document contains a list of team members and authors, a memo to Congress, a table of contents, acknowledgements, recommended citations, a synopsis of the full report, and a preface.
Date: December 2008
Creator: Climate Change Science Program (U.S.)
Partner: UNT Libraries Government Documents Department

Report and Analysis of Test Data From 1998 Trawl Positioning Gear Trails in the Puget Sound Dabob Bay, Washington

Description: A report about a test which can determine which USBL system performs best in conditions that approximate those in Bristol Bay, Alaska. In the future, the Alaska Fisheries Science Center will need to track bottom fishing trawls in order to assess their impact upon the sea floor biology in Alaska.
Date: December 1999
Creator: Connaughey, Robert MC
Partner: UNT Libraries Government Documents Department

[Deepwater Horizon Response and Trial Websites]

Description: Websites related to the Deepwater Horizon oil spill, recovery efforts, and trial. It includes sites established to document corporate and governmental actions to clean up the Gulf of Mexico after the oil spill in 2010, and ongoing efforts to restore ecosystems in the region as well as documentation related to the civil action filed against BP and the subsequent trial.
Date: 2010/2017
Creator: Deepwater Horizon Unified Command
Partner: UNT Libraries Government Documents Department

Deepwater Horizon Response: Gulf of Mexico Oil Spill Response

Description: This website served as the focal point for the Deepwater Horizon Unified Command, a group of organizations that had involvement with the British Petroleum (BP) explosion and oil spill that occurred in the Gulf of Mexico in April 2010. The website includes news feeds and information about health concerns, volunteer opportunities, contact information, and ongoing plans for the area. Various maps of the event and other resources are also available, chronicling the problem and the steps taken by the member organizations to deal with the effects.
Date: September 10, 2010
Creator: Deepwater Horizon Unified Command
Partner: UNT Libraries Government Documents Department

1988 Pilot Institute on Global Change on trace gases and the biosphere

Description: This proposal seeks multi-agency funding to conduct an international, multidisciplinary 1988 Pilot Institute on Global Change to take place from August 7 through 21, 1988, on the topic: Trace Gases and the Biosphere. The institute, to be held in Snowmass, Colorado, is envisioned as a pilot version of a continuing series of institutes on Global Change (IGC). This proposal seeks support for the 1988 pilot institute only. The concept and structure for the continuing series, and the definition of the 1988 pilot institute, were developed at an intensive and multidisciplinary Summer Institute Planning Meeting in Boulder, Colorado, on August 24--25, 1987. The theme for the 1988 PIGC, Trace Gases and the Biosphere, will focus a concerted, high-level multidisciplinary effort on a scientific problem central to the Global Change Program. Dramatic year-to-year increases in the global concentrations of radiatively-active trace gases such as methane and carbon dioxide are now well documented. The predicted climatic effects of these changes lend special urgency to efforts to study the biospheric sources and sinks of these gases and to clarify their interactions and role in the geosphere-biosphere system.
Date: July 1998
Creator: Eddy, J. A. & Moore, B., III
Partner: UNT Libraries Government Documents Department

Evaluation of the anthropogenic radionuclide concentrations in sediments and fauna collected in the Beaufort Sea and northern Alaska

Description: This study was performed to establish a quality controlled data set about the levels of radio nuclide activity in the environment and in selected biota in the U.S. Arctic. Sediment and biota samples were collected by the National Oceanic and Atmospheric Administration (NOAA), the National Biological Service, and the North Slope Borough`s Department of Wildlife Management to determine the impact of anthropogenic radionuclides in the Arctic. The results summarized in this report are derived from samples collected in northwest Alaska with emphasis on species harvested for subsistence in Barrow, Alaska. Samples were analyzed for the anthropogenic radionuclides {sup 90}Sr, {sup 137}Cs, {sup 238}Pu, {sup 239}Pu, {sup 240}Pu and {sup 241}Am. The naturally occurring radionuclides {sup 40}K, {sup 212}Pb and {sup 214}Pb were also measured. One goal of this study was to determine the amounts of anthropogenic radionuclides present in the Beaufort Sea. Sediment samples were isotopically fingerprinted to determine the sources of radio nuclide activities. Biota samples of subsistence and ecological value were analyzed to search for evidence of bio-accumulation of radionuclides and to determine the radiation exposures associated with subsistence living in northern Alaska. The anthropogenic radio nuclide content of sediments collected in the Beaufort Sea was predominantly the result of the deposition of global fallout. No other sources of anthropogenic radionuclides could be conclusively identified in the sediments. The anthropogenic radio nuclide concentrations in fish, birds and mammals were very low. Assuming that ingestion of food is an important pathway leading to human contact with radioactive contaminants and given the dietary patterns in coastal Arctic communities, it can be surmised that marine food chains are presently not significantly affected.
Date: July 1, 1997
Creator: Efurd, D.W.; Miller, G.G. & Rokop, D.J.
Partner: UNT Libraries Government Documents Department

Shoreline Movements, Report 1: Cape Henry, Virginia, to Cape Hatteras, North Carolina, 1849-1980

Description: From addendum: . Part 3 of Technical Report CERC-83-1 describes the general cartographic process used to produce the shoreline position digital data base and maps from which the attached set of 18 composite shoreline position map reproductions were made. The report also describes quality control methods, potential error sources, and probable ranges of error for this process.
Date: July 1983
Creator: Everts, Craig H.; Battley, Jeter P. & Gibson, Peter N.
Partner: UNT Libraries Government Documents Department

Validation of GOES-Derived Surface Radiation Using NOAA's Physical Retrieval Method

Description: This report was part of a multiyear collaboration with the University of Wisconsin and the National Oceanic and Atmospheric Administration (NOAA) to produce high-quality, satellite-based, solar resource datasets for the United States. High-quality, solar resource assessment accelerates technology deployment by making a positive impact on decision making and reducing uncertainty in investment decisions. Satellite-based solar resource datasets are used as a primary source in solar resource assessment. This is mainly because satellites provide larger areal coverage and longer periods of record than ground-based measurements. With the advent of newer satellites with increased information content and faster computers that can process increasingly higher data volumes, methods that were considered too computationally intensive are now feasible. One class of sophisticated methods for retrieving solar resource information from satellites is a two-step, physics-based method that computes cloud properties and uses the information in a radiative transfer model to compute solar radiation. This method has the advantage of adding additional information as satellites with newer channels come on board. This report evaluates the two-step method developed at NOAA and adapted for solar resource assessment for renewable energy with the goal of identifying areas that can be improved in the future.
Date: January 1, 2013
Creator: Habte, A.; Sengupta, M. & Wilcox, S.
Partner: UNT Libraries Government Documents Department

United States Earthquakes, 1928

Description: Report discussing earthquake activity in the United States during 1928. The report is broken down by regions and has sections for specific earthquakes.
Date: 1930
Creator: Heck, N. H. & Bodle, R. R.
Partner: UNT Libraries Government Documents Department

United States Earthquakes, 1929

Description: Report discussing earthquake activity in the United States during 1929. The report is broken down by regions and has sections for specific earthquakes.
Date: 1931
Creator: Heck, N. H. & Bodle, R. R.
Partner: UNT Libraries Government Documents Department

A human Health Perspective on Climate Change: A report Outlining the Research Needs on the Human Health Effects of Climate Change

Description: The Interagency Working Group on Climate Change and Health (iWGCCH) is an ad hoc group formed by participating federal agencies and organizations at the invitation of the National institute of Environmental Health Sciences (NIEHS), National Oceanic and Atmospheric Administration (NOAA), Centers for Disease Control and Prevention (CDC), and Environmental Protection Agency (EPA) following the January 2009 'Workshop on a Research Agenda for Managing the Health Risks of Climate Change, ' sponsored by the Institute of Medicine Roundtable on Environmental Health Sciences, research, and medicine. This report identifies gaps in knowledge of the consequences for human health of climate change, and suggests research to address them. The content, views, and perspectives presented in this report are solely those of the authors, and do not reflect the official views, policies, or implied endorsement of any of the individual participating federal agencies or organizations.
Date: April 22, 2010
Creator: Interagency Working Group on Climate Change and Health (U.S.)
Partner: UNT Libraries Government Documents Department

Energy Analysis Program, Annual Report: 1994

Description: This report provides an energy analysis overview. The following topics are described: building energy analysis; urban and energy environmental issues; appliance energy efficiency standards; utility planning and policy; energy efficiency, economics, and policy issues; and international energy and environmental issues.
Date: April 1, 1995
Creator: Levine, M.D.
Partner: UNT Libraries Government Documents Department

A U.S. Carbon Cycle Science Plan

Description: Report assessing the carbon cycle and providing guidance for U.S. researchers. It includes background on the history and context of the carbon cycle and previous science plan as well as chapters describing relevant fundamental science questions, science plan goals, the plan elements, interdisciplinary and international collaboration and cooperation, implementation and funding of the plan, and references with supplementary appendix information.
Date: August 2011
Creator: Michalak, Anna M.; Jackson, Robert B.; Marland, Gregg & Sabine, Christopher L.
Partner: UNT Libraries

United States Earthquakes, 1930

Description: Report discussing earthquake activity in the United States during 1930. The report is broken down by regions and has sections for specific earthquakes.
Date: 1932
Creator: Neumann, Frank & Bodle, R. R.
Partner: UNT Libraries Government Documents Department

Long-Term Monitoring at the East and West Flower Garden Banks National Marine Sanctuary, 2002-2003: Final Report

Description: Final report of 2002-2003 monitoring of habitat and marine life of the East and West Flower Garden Banks National Marine Sanctuary in the Gulf of Mexico
Date: September 2006
Creator: Precht, William F.; Aronson, Richard B.; Deslarzes, Kenneth J. P.; Robbart, Martha L.; Murdoch, Thaddeus J. T.; Gelber, Adam et al.
Partner: UNT Libraries Government Documents Department