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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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At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1980

Detection of heavy convective precipitation using rapid interval digital radar and satellite data

A study was carried out to investigate the evolution of thunderstorms with short-interval (5 min) geosynchronous digital satellite data and with digital radar data (12 min interval) in order to determine the potential and limitations of using the satellite data to detect regions of heavy convective precipitation. Initial results indicate that satellite-based estimates of thunderstorm updraft intensity are related to storm precipitation rate as indicated in the digital radar data. The conclusions give support to the effort to use satellite data for detection of heavy convective precipitation, but emphasize the need for high time resolution (5 min) data.

Negri, A. J.↗
NASA NTRS1981

Cloud cover archiving on a global scale - A discussion of principles

Monitoring of climatic variability and climate modeling both require a reliable global cloud data set. Examination is made of the temporal and spatial variability of cloudiness in light of recommendations made by GARP in 1975 (and updated by JOC in 1978 and 1980) for cloud data archiving. An examination of the methods of comparing cloud cover frequency curves suggests that the use of the beta distribution not only facilitates objective comparison, but also reduces overall storage requirements. A specific study of the only current global cloud climatology (the U.S. Air Force's 3-dimensional nephanalysis) over the United Kingdom indicates that discussion of methods of validating satellite-based data sets is urgently required.

Henderson-Sellers, A.↗
NASA NTRS1981

Solar radiation monitoring for high altitude aircraft

Ground-based and satellite-based ionizing radiation monitoring systems are considered as alternative methods for ensuring safe radiation levels for high-altitude aircraft. It is found that ground-based methods are of limited accuracy due to insensitivity to solar particles of energies between the riometer upper cutoff of about 50 MeV and the neutron monitor threshold of about 450 MeV. This energy range is demonstrated to be essential for atmospheric radiation monitoring at high altitude, and must be covered by satellite measurement. On the basis of presently available data, the accuracy to which the incident solar particle flux must be measured by satellite-borne detectors is examined and recommendations are made to establish minimum requirements.

Wilson, J. W.↗
NASA NTRS1982

Global distribution of stratospheric aerosols by satellite measurements

A description is given of the first-ever global stratospheric aerosol climatology which is being developed by the earth-orbiting SAM II and SAGE satellite-based sensors. These sensors use the technique of solar occulation; that is, for every spacecraft sunrise and sunset, the modulation of solar intensity caused by the intervening earth-limb is measured. These data are mathematically inverted to yield vertical profiles of aerosol extinction coefficients with 1 km resolution. The data show seasonal variations which are similar in each hemisphere, with strong correlation between aerosol extinction and the corresponding temperature field. Typical values of extinction in the stratosphere are found to be about 0.0001 to 0.0002 per km at 1 micrometer; stratospheric optical depths at this wavelength are about 0.002. The peak extinction in the stratospheric aerosol layer follows the tropopause with altitude, with peak extinction ratios about 10 km above the local tropopause.

Mccormick, M. P.↗
NASA NTRS1982

The chromospheres of classical Cepheids. I - Low resolution IUE spectra

A program to study the behavior of chromospheres in classical Cepheids using both ground-based and satellite-based observations. Five stars, delta Cep, nu Aql, beta Dor, zeta Gem, and l Car, have been included, and where possible the various types of data have been obtained simultaneously. The first part of this investigation concerns low dispersion spectra from the IUE satellite. Fine error sensor (FES) magnitudes are presented for the five Cepheids and, in the case of one, nu Aql, are used to rediscuss the period. The 'artificial viscosity dip' predicted by some theoretical calculations may be present in the FES light curve of delta Cep. The low dispersion spectra have been used to determine continuum magnitudes at various UV wavelengths, and light curves are shown. The amplitude increases with decreasing wavelength except around 1550 A. Line emission in the short wavelength region is observed in three of the Cepheids and is found to be phase dependent. Some correspondence is found between the variation of the emission lines and the appearance of bumps on the UV light curves.

Schmidt, E. G.↗
NASA NTRS1982

Orbit determination of geosynchronous satellites by VLBI and differential VLBI

Four approaches to radio interferometric tracking of geosynchronous satellites are analyzed and compared. Quasar-based differential very-long-baseline interferometry, which requires a very sensitive receiver, can achieve meter-level position accuracy with a two-baseline system. Satellite-based differential VLBI gives somewhat lower accuracy with a compact, inexpensive receiver. Nondifferential VLBI, using less precise media and clock calibrations obtained by observing the GPS satellites, still gives 5-10 m position accuracy with two baselines. For a sufficiently inclined orbit, all interferometric approaches can yield six-component satellite state from a single baseline.

Yunck, T. P.↗
NASA NTRS1982

DE-1 observations of VLF transmitter signals and wave-particle interactions in the magnetosphere

A broadband VLF receiver on the DE-1 satellite measures signals injected into the magnetosphere by ground-based transmitters. VLF emissions triggered by these signals indicate that the waves interact strongly with trapped energetic particles in the magnetosphere. The propagation paths from the source to the satellite are deduced on the basis of the group time delay and Doppler shift. Although there are many different paths, emissions are triggered by the later-arriving pulses that have traversed the geomagnetic equator. First satellite-based observations of emission triggering by high-power communications transmitters and their possible implications are discussed.

Inan, U. S.↗
NASA NTRS1982

Energy Facility Siting by Means of Environmental Modelling with LANDSAT, Thematic Mapper and Geographic Information System (GIS) Data

Currently based on ground and aerial surveys, the land cover data base of the Pennsylvania Power and Light Company is routinely used for modelling the effects of alternative generating plant and transmission line sites on the local and regional environment. The development of a satellite-based geographic information system would facilitate both the preparation of environmental impact statements by power companies and assessment of the data by the Nuclear Regulatory Commission. A cooperative project is planned to demonstrate the methodology for integrating satellite data into an existing geographic information system, d to further evaluate the ability of satellite data in modeling environmental conditions that would be applied in the preparation and assessment of environmental impact statements.

Source record↗
NASA NTRS1983

Satellite freeze forecast system: Executive summary

A satellite-based temperature monitoring and prediction system consisting of a computer controlled acquisition, processing, and display system and the ten automated weather stations called by that computer was developed and transferred to the national weather service. This satellite freeze forecasting system (SFFS) acquires satellite data from either one of two sources, surface data from 10 sites, displays the observed data in the form of color-coded thermal maps and in tables of automated weather station temperatures, computes predicted thermal maps when requested and displays such maps either automatically or manually, archives the data acquired, and makes comparisons with historical data. Except for the last function, SFFS handles these tasks in a highly automated fashion if the user so directs. The predicted thermal maps are the result of two models, one a physical energy budget of the soil and atmosphere interface and the other a statistical relationship between the sites at which the physical model predicts temperatures and each of the pixels of the satellite thermal map.

Martsolf, J. D.↗
NASA NTRS1981

The promise of remote sensing in the atmospheric sciences

The applications and advances in remote sensing technology for weather prediction, mesoscale meteorology, severe storms, and climate studies are discussed. Doppler radar permits tracking of the three-dimensional field of motion within storms, thereby increasing the accuracy of convective storm modeling. Single Doppler units are also employed for detecting mesoscale storm vortices and tornado vortex signatures with lead times of 30 min. Clear air radar in pulsed and high resolution FM-CW forms reveals boundary layer convection, Kelvin-Helmoltz waves, shear layer turbulence, and wave motions. Lidar is successfully employed for stratospheric aerosol measurements, while Doppler lidar provides data on winds from the ground and can be based in space. Sodar is useful for determining the structure of the PBL. Details and techniques of satellite-based remote sensing are presented, and results from the GWE and FGGE experiments are discussed.

Atlas, D.↗
NASA NTRS1983

Sensitivity of ozone retrievals in limb-viewing experiments to errors in line-width parameters

The variance of atmospheric ozone concentration profiles retrieved in i.r. limb-viewing experiments is examined over the range of published ozone halfwidth values. Simulated retrievals are performed for a typical satellite-based high-resolution absorption experiment and a broad-band emission experiment. The results indicate that, for limb-viewing experiments, inaccurate collision-broadened linewidth values can lead to significant errors in retrieved profiles for broad-band radiometric data or for isolated strong lines in high-resolution spectra.

Smith, M. A. H.↗
NASA NTRS1982

Satellite-aided land mobile communications system implementation considerations

It was proposed that a satellite-based land mobile radio system could effectively extend the terrestrial cellular mobile system into rural and remote areas. The market, technical and economic feasibility for such a system is studied. Some of the aspects of implementing an operational mobile-satellite system are discussed. In particular, two key factors in implementation are examined: (1) bandwidth requirements; and (2) frequency sharing. Bandwidth requirements are derived based on the satellite antenna requirements, modulation characteristics and numbers of subscribers. Design trade-offs for the satellite system and potential implementation scenarios are identified. Frequency sharing is examined from a power flux density and modulation viewpoint. Previously announced in STAR as N82-25290

Leroy, B. E.↗
NASA NTRS1982

An analysis of the multibeam altimeter

The design concept and computer simulations of a multibeam altimeter (MA) to provide satellite-based oceanographic-feature data for map construction within relatively short times are presented. The limitations of the pulse-limited radar altimeter used on GEOS-3 and SEASAT-A, in particular the narrow swath of each measurement pass, are characterized. The MA uses interferometry with two 1.2-m dish antennas separated by an 11-m boom to cover a total swath width of 100 km at satellite altitude 800 km, nominal repetition rate 6 kp/sec, and nominal integration time 2.5 sec. Simulation analysis of antenna element pattern, echo shape, tracking algorithms, tracking noise, and measurement accuracy was performed, and the general feasibility of ocean-current mapping with a one-week time delay, using two MA-equipped satellites, was demonstrated.

Bush, G. B.↗
NASA NTRS1983

Characteristics of RF Lightning Emission at 2 Ghz and 250 Mhz

Radio frequency emissions in the S-band and VHF range from lightning discharges are recorded by a facility developed at MSFC as part of a feasibility study of a satellite-based lightning mapping system. The recording facility receives RF emissions in both vertical and horizontal polarization and stores the data on magnetic tape. Output from any one antenna may also be selected for high speed digitization and disk storage. Improvement in both hardware and software have enhanced significantly the accuracy of data characterization and the speed of data collection. Emission records at VHF have higher signal strength than the S-band as expected. The records of cloud-to-ground discharges obtained so far give a 7-33 V/M peak equivalent signal strength (1 KHz at 10 kilometer) in the S-band range. The CG discharge structure is recognizable in most of the data collected. Considerable RF activity is present throughout the VHF records. The S-band data shows signals associated with limited portions of discharge history. The records obtained are from lightning activities within a 10 mile range.

Jalali, F.↗
NASA NTRS1984

Oceanic Transport

The importance of large-scale ocean movements to the moderation of Global Temperature is discussed. The observational requirements of physical oceanography are discussed. Satellite-based oceanographic observing systems are seen as central to oceanography in 1990's.

Chase, R.↗
NASA NTRS1983

Remote assessment of ocean color for interpretation of satellite visible imagery: A review

An assessment is presented of the state-of-the-art of remote, (satellite-based) Coastal Zone Color (CZCS) Scanning of color variations in the ocean due to phytoplankton. Attention is given to physical problems associated with ocean color remote sensing, in-water algorithms for the correction of atmospheric effects, constituent retrieval algorithms and application of the algorithms to CZCS imagery. The applicability of CZCS to both near-coast and mid-ocean waters is considered, and it is concluded that while differences between the two environments are complex, universal algorithms can be used for the case of mid-ocean waters, and site-specific algorithms are adequate for CZCS imaging of the near-coast oceanic environment. A short description of CVCS and some sample photographs are provided in an appendix.

Gordon, H. R.↗
NASA NTRS1982

Infrared Data for Storm Analysis

The papers in this section include: 1) 'Thunderstorm Top Structure Observed by Aircraft Overflights with an Infrared Radiometer'; 2) 'Thunderstorm Intensity as Determined from Satellite Data'; 3) 'Relation of Satellite-Based Thunderstorm Intensity to Radar-Estimated Rainfall'; 4) 'A Simple Physical Basis for Relating Geosynchronous Satellite Infrared Observations to Thunderstorm Rainfall'; 5) 'Satellite-Observed Cloud-Top Height Changes in Tornadic Thunderstorms'; 6) 'Predicting Tropical Cyclone Intensity Using Satellite-Measured Equivalent Blackbody Temperatures of Cloud Tops'.

Adler, R.↗
NASA NTRSDate not supplied

NASA POWER: Providing Analysis-Ready, Cloud-Optimized Data for AI /ML Training and Applications in Earth Science

As global demand for sustainable development grows, the integration of Earth Observation (EO) data into decision making frameworks has become a primary objective for the scientific community. The NASA Prediction of Worldwide Energy Resources (POWER) project serves as a bridge between NASA EO data and the specialized needs of the renewable energy, sustainable infrastructure and agroclimatology communities. In this poster presentation we will present an overview of POWER data products and services along with its use in diverse research to decision-making workflows. By providing over 40 years of high-resolution historical, hourly and daily solar and meteorological data, POWER transforms satellite observations and global model reanalysis into actionable, Analysis-Ready Dataset (ARD). Currently, the project delivers over 250 industry-friendly parameters to the users from different NASA datasets like CERES SYN1Deg, MERRA-2, and IMERG alongside downscaled CMIP6 climate model data, fulfilling over 16 million requests from 50,000 unique users monthly. To ensure data quality and traceability, these parameters are rigorously validated against the ground-based observations from the Baseline Surface Radiation Network (BSRN) and the Global Surface Summary of the Day (GSOD) – these results will be discussed in the presentation. A newly introduced web-based PaRameter Uncertainty ViEwer (PRUVE) tool will be presented that provides an online validation platform to the users that benchmarks satellite-based and assimilation data products against these surface measurements. To reduce technical barriers to data adoption, POWER data is accessible through RESTful APIs, ESRI ArcGIS Image Services, a web-based Data Access Viewer tool, allowing users to visualize, validate and apply the dataset. For efficient data delivery POWER data is cloud-optimized into Zarr datastore accessible through NASA managed Amazon S3 ensures high-performance allowing users to integrate EO directly into operational pipelines. These customized services will be presented. Use cases from application will be presented from the energy sector - such as for design of generation systems, performance monitoring of solar power plants, in infrastructure sector- optimizing building energy efficiency and thermal comfort, in agriculture – such as driving crop simulation and yield forecasting models to enable climate resilient farming. Furthermore, the shift toward machine learning (ML) in EO research that has positioned POWER as a key provider for training datasets which will be discussed. Use-cases will be presented to showcase how NASA data is enabling the development of predictive tools for climate variability and resource management. The poster will present POWER’s future plans including technology development to enhance data traceability and reproducibility and improving I/O performance to support the rapid integration of new EO products, ensuring that POWER remains a robust scalable backend for the evolving landscape of AI-driven Earth Science. Additionally, POWER is developing an AI Agent and an MCP-Server to enable industry AI-Agentic workflows.

Neha Khadka↗