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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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NASA NTRS1976

Contributions to the National Geodetic Satellite Program by Goddard Space Flight Center

The major scientific contributions of Goddard Space Flight Center to the National Geodetic Satellite Program between 1965 and 1973 are presented and discussed. The primary results described are the determination of the earth's gravitational field from satellite tracking and surface gravimeter data to an accuracy of about 4 mGal for wavelengths of about 1000 km and larger; the construction of a detailed geoid suitable for geodetic, tectonic, and altimetry data analysis accurate to about 2 m over continents and to 2-5 m over the northeast Pacific and Atlantic oceans; and the positioning of globally distributed tracking stations to an accuracy of 5-10 m for the interconnecting of local geodetic datums. In addition, work on the observation of the earth and ocean tidal perturbations of satellites is discussed and reviewed.

Smith, D. E.↗
NASA NTRS1976

Organic constituents in eolian dust and surface sediments from northwest Africa

Samples of eolian dust and comparably sized desert surface sediment samples collected over widely scattered regions of northwest Africa were analyzed for carbon, nitrogen, and hydrogen content and total carbohydrate. Infrared analysis and gas chromatographic analysis were also performed on organic components extracted from several of these samples. Although the total carbon content of the eolian dust samples varies from 2.8 to 7.0% by weight, the organic carbon component is relatively uniform at 2.9 + or - 0.5%. By comparison, the average organic carbon content of the African surface sediments is 0.7 + or - 0.5%. Total carbohydrate content averages 0.128% for the dust and 0.022% for the desert sediments. It is shown that these desert regions are not presently the principal sources of eolian material transported over the North Atlantic Ocean.

Lepple, F. K.↗
NASA NTRS1977

Investigation of the applications of GEOS-3 radar altimeter data in remote sensing of land and sea features

A number of GEOS-3 passes over the Atlantic Ocean and Southeastern U.S. are examined. Surface-truth and radar altimeter data comparisons are given in terms of surface correlation length, signal fluctuation characteristics, and altitude tracker dynamic response. Detailed analyses are given regarding spatial resolution and its dependency on angular backscatter behavior. These analyses include data from passes over ocean (diffuse scatter), land (large body scatter), and mirror-like inland water areas (pseudo-specular scatter). Altimeter data are examined for a pass over a large reservoir and marsh area of differing water levels; this geometry represents a stepchange in altitude which is usable in determination of the transient response of the tracker. The extent to which pulse-length limited operation pertains over-land is examined. A Wiener filter altitude algorithm is discussed which permits specification of tracker variance and geoidal spectral characteristics during operation.

Miller, L. S.↗
NASA NTRS1977

Study of the Brazil and Falkland currents using their images of Nimbus 5 and oceanographic data in 1972 - 1973

The Western Edge of the Sub-tropical Convergence of the South-western Atlantic Ocean, called the Front, which is a thermal discontinuity between the Brazil and Falkland Currents, was studied utilizing the Temperature Humidity Infrared Radiometer (THIR) of Nimbus V in the 10.5 to 12.5 micrometers channel and historical oceanographic data. Some important results obtained are: the oceanographic Front could be detected from Nimbus THIR data; oceanographic charts showed that the transition zone where the Brazil and the Falkland Currents meet was the Front detected from satellite data; ocean current speeds calculated with THIR data were of the same order of magnitude as those calculated oceanographically; fisheries statistics for Pargo Roseo showed that the maximum catches were in September of 1973, in the period when the Front was observed most distinctly and clearly. The results showed the great potentiality of satellite data to study surface thermal structures, surface currents and oceanic fisheries.

Tseng, Y. C.↗
NASA NTRS1978

Short arc reduction of radar altimetry computer program

The Air Force Geophysics Laboratory computer program SARRA (Short Arc Reduction of Radar Altimetry) has been used for geoid determination with altimetric observations from the GEOS-3 satellite. An important feature of SARRA is the simultaneous recovery of the orbit parameters and the surface coefficients as defined by covariance function weights. Orbits good to approximately 20 meters are adequate for precise geoid determinations by virtue of the orbital adjustment in the reductions. Altimetric data over a portion of the North Atlantic Ocean have been processed to derive the regional geoid and gravity field. Analyses of altimeter residuals resulting from the short arc adjustment show that the residuals can be used to define the neglected higher order geoidal undulations with high fidelity and continuity.

Hadgigeorge, G.↗
NASA NTRS1978

NATO-3C/Delta launch

NATO-3C, the third in a series of NATO defense-related communication satellites, is scheduled to be launched on a delta vehicle from the Eastern Test Range no earlier than November 15, 1978. NATO-3A and -3B were successfully launched by Delta vehicles in April 1976 and January 1977, respectively. The NATO-3C spacecraft will be capable of transmitting voice, data, facsimile, and telex messages among military ground stations. The launch vehicle for the NATO-3C mission will be the Delta 2914 configuration. The launch vehicle is to place the spacecraft in a synchronous transfer orbit. The spacecraft Apogee Kick motor is to be fired at fifth transfer orbit apogee to circularize its orbit at geosynchronous altitude of 35,900 km(22,260 miles) above the equator over the Atlantic Ocean somewhere between 45 and 50 degrees W longitude.

Source record↗
NASA NTRS1977

Sea-surface temperature and salinity mapping from remote microwave radiometric measurements of brightness temperature

A technique to measure remotely sea surface temperature and salinity was demonstrated with a dual frequency microwave radiometer system. Accuracies in temperature of 1 C and in salinity of part thousand for salinity greater than 5 parts per thousand were attained after correcting for the influence of extraterrestrial background radiation, atmospheric radiation and attenuation, sea-surface roughness, and antenna beamwidth. The radiometers, operating at 1.43 and 2.65 GHz, comprise a third-generation system using null balancing and feedback noise injection. Flight measurements from an aircraft at an altitude of 1.4 km over the lower Chesapeake Bay and coastal areas of the Atlantic Ocean resulted in contour maps of sea-surface temperature and salinity with a spatial resolution of 0.5 km.

Hans-Juergen, C. B.↗
NASA NTRS1979

Comparison of backscatter ultraviolet /BUV/ and ground-based total ozone fields for December 1970

For the period December 1970, comparison is made between the monthly average analyses (mapped fields) of the backscatter ultraviolet (BUV) total ozone data and the ground-based observations. In particular, significant differences of over 50 Dobson units are noted over the region of the North Atlantic Ocean with the BUV of greater magnitude than the ground-based data. As part of the overall verification program, both analyses are compared against the 100 mb height fields. The results indicate that the BUV analysis in the region of question is the more consistent of the two.

Miller, A. J.↗
NASA NTRS1979

Geos 3 wave height measurements - An assessment during high sea state conditions in the North Atlantic

The sea state in the North Atlantic Ocean has been monitored in February, 1977 to obtain data for verification of Geos 3 radio altimeter wave form data. The altimeter sea state data were found to be in good agreement with in situ sea state measurements and with aircraft remote sensing measurements of wave height. The average difference between the supporting data and Geos 3 was 0.34 m, and the standard deviation 0.61 m. Contour maps of sea state constructed for large regions of the earth's oceans on the basis of Geos 3 altimeter measurements exhibited systematic differences from operationally available computerized maps. It is thought that the underestimation of significant wave height maxima in the operational maps and the underestimation of the speed of movement of oceanic cyclones may be due to basic errors in the output of atmospheric primitive-equation models. Because of the narrow swath width of the Geos-3 sensor, data from several satellite orbits must be combined to construct contour maps, leading to low values of significant wave heights.

Parsons, C. L.↗
NASA NTRS1980

Project Intelsat 5

With 12,000 voice circuits and 2 television channels, intelsat 5, the first of a new generation of international telecommunication satellites, has almost double the communication capability of early satellites in the series. The 1,928 kilogram (at a lunch) satellite will be placed into geosynchronous orbit over the Atlantic Ocean to provide communications between North America and Europe. The characteristics of the Atlas Centaur launch vehicle to be used are described and the flights events of the launch sequence are tabulated.

Source record↗
NASA NTRS1981

Research of the state of convection in the Earth's mantle

The behavior and mechanical properties of the lithosphere are studied. Geoid heights derived from the GEOS 3 and SEASAT radar altimeters were used. The following predictive capabilities are discussed: location of unknown seamounts from the knowledge of the geoid heights; prediction of gravity field from the knowledge of the topography and past history of the relief; or insight into the history of a region from the knowledge of both topography and geoid heights. Several geographical areas were studied, including the Walvis Ridge and Rio Grande Rise in the Southern Atlantic Ocean and several seamount chains in the Central Pacific Ocean. Two main factors influence geoid height: conditions of creation and age of the lithosphere at the time of loading.

Roufosse, M. C.↗
NASA NTRS1980

Planetary boundary-layer wind model evaluation at a mid-Atlantic coastal site

Detailed measurements of the mean flow and turbulence were made with the use of a micrometeorological facility consisting of an instrumented 76-m tall tower located within a 100-m distance from the Atlantic Ocean at Wallops Island, Virginia. Under moderately strong wind conditions, the popular neutral boundary layer flow model fails to provide an adequate description of the actual flow. In addition to detailed flow information for all wind directions, averages of the important flow parameters used for design such as vertical distribution of mean velocity, turbulence intensities and turbulence integral scales were presented for wind direction sectors with near uniform upstream terrain. Power spectra of the three velocity components for the prevailing northwesterly and southerly winds are discussed.

Tieleman, H. W.↗
NASA NTRS1980

The structure of moderately strong winds at a mid-Atlantic coastal site /below 75m/

Velocity and temperature measurements were obtained from an instrumented 76-meter meteorological tower located near the Atlantic Ocean at Wallops Island, Virginia. The instrumentation consists of a slow-response cup-vane and resistance temperature system and a hot-film, thermocouple system for turbulence measurements. Results are presented for moderately strong winds from westerly directions (category I) and for on-shore winds from southerly directions (category II). Results from category I winds indicate the presence of low-frequency velocity fluctuations affecting all turbulence parameters similar to the observations made in Kansas and Minnesota. Winds of category II experience a change in surface roughness and surface temperature as they cross the coast line, resulting in the development of an internal boundary layer. The stable ocean air above the IBL shows extremely low turbulence levels (less than 3%). Because of the lack of turbulent mixing with adjacent layers, Coriolis effects are important and profiles with a maximum velocity at heights between 60-200 m exist.

Tieleman, H. W.↗
NASA NTRS1980

Production of NO2/-/ and N2O by nitrifying bacteria at reduced concentrations of oxygen

The influence of oxygen concentration on the production of NO2(-) and N2O by nitrifying marine bacteria of the genus Nitrosomonas is investigated. Pure cultures of the ammonium-oxiding bacteria isolated from the Western Tropical Atlantic Ocean were grown at oxygen partial pressures from 0.005 to 0.2 atm, and concentrations of N2O in the air above the growth medium and dissolved NO2(-) were determined. Decreasing oxygen concentrations are observed to induce a marked decrease in NO2(-) production rates and increase in N2O evolution, leading to an increase of the relative yield of N2O with respect to NO2(-) from 0.3% to nearly 10%. Similar yields of N2O at atmospheric oxygen levels are found for nitrifying bacteria of the genera Nitrosomonas, Nitrosolobus, Nitrosospira and Nitrosococcus, while nitrite-oxydizing bacteria and a dinoflagellate did not produce detectable quantities of N2O. Results support the view that nitrification is a major source of N2O in the environment.

Goreau, T. J.↗
NASA NTRS1981

Bacterial biomass and heterotrophic potential in the waters of the Chesapeake Bay plume and contiguous continental shelf

Seasonal baseline data on bacterial biomass and heterotrophic uptake in the Chesapeake Bay plume and contiguous Atlantic Ocean shelf waters are discussed. Viable count bacterial numbers in surface water samples collected during June 1980 ranged from a maximum of 190,000 MPN (most probable number)/ml at the Bay mouth to a minimum of 7900 MPN/ml offshore. Similarly, direct count densities ranged from 1,800,000 BU (bacterial units)/ml to 24,000 BU/ml. Heterotrophic potential (V max) was largest at the Bay mouth and lowest offshore. Biomass and V max values usually decreased with depth although subsurface maxima were occasionally observed at inshore stations. Correlation of biomass and heterotrophic potential data with selected hydrographic variables was determind with a nonparametric statistic. Results indicate viable counts are positively and significantly correlated with total chlorophyll, temperature, direct count and V max during June 1980; significant negative correlations are obtained with salinity and depth. Calculations of bacterial standing crop are discussed.

Kator, H. I.↗
NASA NTRS1981

SAGE measurements of the stratospheric aerosol dispersion and loading from the Soufriere Volcano

Explosions of the Soufriere volcano on the Caribbean Island of St. Vincent reduced two major stratospheric plumes which the stratospheric aerosol and gas experiment (SAGE) satellite tracked to West Africa and the North Atlantic Ocean. The total mass of the stratospheric ejecta measured is less than 0.5% of the global stratospheric aerosol burden. No significant temperature or climate perturbation is expected. It is found that the movement and dispersion of the plumes agree with those deduced from high altitude meteorological data and dispersion theory. The stratospheric aerosol dispersion and loading from the Soufrier volcano was measured.

Mccormick, M. P.↗
NASA NTRS1981

Investigation from Japanese MAGSAT Team. Part A. Crustal structure near Japan and in Antarctic station. Part B. Electric currents and hydromagnetic waves in the ionosphere and the magnetosphere

Preliminary results of MAGSAT data analysis are described. Regional anomaly maps (deviations from the MGST model field) for X,Y,Z, and F in the area of 115 to 155 deg E and 20 to 60 deg N were obtained. A similar map for the geomagnetic total force anomaly in the vicinity of Japan showed that the observed anomaly can be explained by the difference in crustal magnetization between the Japan Sea and the Japan Island, which reflects a difference of 25 km in the thickness of the magnetized layer. The MAGSAT record of a sudden commencement of a magnetic storm above the South Atlantic Ocean showed a reverse impulse particularly in the D-component. Results relating to toroidal currents in the ionosphere, transverse and parallel perturbations over the polar regions, the relationship between field aligned currents and precipitating electrons, and the calculation of the subsatellite electric field are also discussed.

Fukushima, N.↗
NASA NTRS1981

A study of atmospheric diffusion from the LANDSAT imagery

LANDSAT multispectral scanner data of the smoke plumes which originated in eastern Cabo Frio, Brazil and crossed over into the Atlantic Ocean, are analyzed to illustrate how high resolution LANDSAT imagery can aid meteorologists in evaluating specific air pollution events. The eleven LANDSAT images selected are for different months and years. The results show that diffusion is governed primarily by water and air temperature differences. With colder water, low level air is very stable and the vertical diffusion is minimal; but water warmer than the air induces vigorous diffusion. The applicability of three empirical methods for determining the horizontal eddy diffusivity coefficient in the Gaussian plume formula was evaluated with the estimated standard deviation of the crosswind distribution of material in the plume from the LANDSAT imagery. The vertical diffusion coefficient in stable conditions is estimated using Weinstock's formulation. These results form a data base for use in the development and validation of meso scale atmospheric diffusion models.

Dejesusparada, N.↗