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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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60 records · Page 4

Suburb-to-suburb intercity travel: Energy, time and dollar expenditures

The effect of adding suburb to terminal and terminal to suburb travel is examined. The energy consumed in entire trips was estimated. The total energy costs are compared with total travel times, and dollar costs to the traveler. Trips between origins in seven suburbs of Newark, New Jersey and destinations in two Washington, D. C. suburbs are analyzed.

Fels, M. F.↗

Observations and theory of the solar semidiurnal tide in the mesosphere of Venus

The 1978 Pioneer Venus mission, in addition to producing strong IR radiometer experiment evidence for the existence of a semidiurnal solar tide in the Venus mesosphere, has yielded radiative flux and cloud particle distribution data about the structure of solar heating and IR cooling which facilitate calculations of tidal forcing functions and estimates of radiative dissipation rates. It is presently shown that a physically reasonable mean flow can be found which leads to theoretically predicted tides that are in excellent agreement with those observed. The zonal mean flow obtained exhibits a maximum velocity of about 130 m/sec at 70 km altitude, decreasing to about zero at 88 km, together with a jet-like meridional structure that strongly deviates from solid body rotation.

Fels, S. B.↗

Radiative processes

Solar radiation and the processes that control its deposition in the Earth atmosphere are considered. The published data obtained since 1978 define a reference solar spectral irradiance for use in atmospheric chemical and dynamical studies, while long term satellite measurements are now providing information on variations in the output of the Sun over a range of time scales. As concerns absorption of solar radiation in the atmosphere, new cross section data for molecular oxygen and ozone are now available. Line-by-line calculations used to predict infrared flux divergences, both as regards assumptions made in radiative transfer calculations and in the spectroscopic parameters used as inputs are examined. Also examined are the influence of radiative processes on planetary scale wave activity, photochemical acceleration of radiative damping, and the breakdown of local thermodynamic equilibrium at mesospheric altitudes.

Frederick, J. E.↗

Infrared cooling rate calculations in operational general circulation models - Comparisons with benchmark computations

The performance of several parameterized models is described with respect to numerical prediction and climate research at GFDL, NCAR, and GISS. The radiation codes of the models were compared to benchmark calculations and other codes for the intercomparison of radiation codes in climate models (ICRCCM). Cooling rates and fluxes calculated from the models are examined in terms of their application to established general circulation models (GCMs) from the three research institutions. The newest radiation parameterization techniques show the most significant agreement with the benchmark line-by-line (LBL) results. The LBL cooling rates correspond to cooling rate profiles from the models, but the parameterization of the water vapor continuum demonstrates uncertain results. These uncertainties affect the understanding of some lower tropospheric cooling, and therefore more accurate parameterization of the water vapor continuum, as well as the weaker absorption bands of CO2 and O3 is recommended.

Kiehl, J. T.↗

Trends in stratospheric temperature

Stratospheric temperatures for long-term and recent trends and the determination of whether observed changes in upper stratospheric temperatures are consistent with observed ozone changes are discussed. The long-term temperature trends were determined up to 30mb from radiosonde analysis (since 1970) and rocketsondes (since 1969 and 1973) up to the lower mesosphere, principally in the Northern Hemisphere. The more recent trends (since 1979) incorporate satellite observations. The mechanisms that can produce recent temperature trends in the stratosphere are discussed. The following general effects are discussed: changes in ozone, changes in other radiatively active trace gases, changes in aerosols, changes in solar flux, and dynamical changes. Computations were made to estimate the temperature changes associated with the upper stratospheric ozone changes reported by the Solar Backscatter Ultraviolet (SBUV) instrument aboard Nimbus-7 and the Stratospheric Aerosol and Gas Experiment (SAGE) instruments.

Schoeberl, M. R.↗