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Roderick S. Quiroz and Robert M. Henry

Abstract

Eight ARCAS meteorological rockets were fired from Wallops Island (38N, 75W) before, during and after the total solar eclipse of 7 March 1970. Detailed temperature and wind data were acquired to an altitude of about 65 km. Pressures and densities were derived by hydrostatic integration of the corrected temperature profiles. A time-height cross section of the temperature data (smoothed to suppress small-scale detail) shows significant cooling mainly in the layer 40–60 km. Maximum amplitude of the temperature perturbation is about 9K, near 50 km. Maximum pressure variation, amounting to a decrease of at least 7%, occurred about one scale height higher, near 58 km. The ARCAS wind observations are independent of the thermodynamic measurements; a time-height analysis of the winds shows a large amplification of the meridional flow, which is found to be consistent with the observed pressure changes. Derivatives in the perturbation equation of motion are evaluated with the aid of a space-time transformation based on the speed of the eclipse shadow. Consistency between the wind and thermodynamic data is indicated by approximately a three-fold increase, with altitude, of both the observed perturbation wind and the geostrophic wind specified by the perturbation model. Evidence supporting the observed temperature variation includes not only the ARCAS wind data, but also Pitot-probe and balloon measurements at Wallops Island and falling-sphere eclipse measurements in Florida. The cooling rate observed in the eclipse exceeds computed cooling rates at 50 km.

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Robert M. Henry and Seymour L. Hess

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Methods are developed for determining the contribution by each harmonic wave component to the geostrophic kinetic energy of meridional and zonal motion, and to the geostrophic fluxes of angular momentum and enthalpy. Evaluations are carried out for each day of January 1951 for selected latitudes and pressure surfaces and the resulting spectral distributions discussed. Salient features are large spatial and temporal variations of the energy spectra and unexpectedly large contributions by the lower wave numbers to the fluxes of momentum and heat.

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Harold B. Tolefson and Robert M. Henry

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Harold N. Murrow and Robert M. Henry

Abstract

Rigid spherical balloons were released in still air to assess magnitudes of possible self-induced motion. They were found to exhibit oscillations similar to those previously reported for rubber balloons. These oscillations are not simple sinusoidal motion, and are not limited to a single plane. The root-mean-square horizontal velocity is proportional to the vertical terminal velocity, and for the ROSE sphere appears to he one-half the terminal velocity. Slight roughening (roughness ratio = 0.0016) had no apparent effect. Greater roughness (roughness ratio = 0.03) appears to reduce the amplitude and predominant wavelength of the oscillation.

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Robert M. Henry and James A. Cochrane

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The variation in winds and resulting variations in wind loads on vertically launched vehicles for different worldwide geographical areas are investigated. Methods of determining possible alternate launch sites that offer distinct windwise advantages over presently used sites are discussed; reductions of 50 per cent or more in statistically determined peak winds or in statistical values of wind shears at critical altitudes may be realized. Since peak winds and maximum shears are recognized parameters of wind-induced loading, the variations in peak loads that are expected at different launch sites should reflect significant changes in wind environment with geographical regions. For some particular vehicles, variation of a single parameter, such as maximum wind speed, will produce large differences in computed load histories. An interesting disclosure of subjecting a simulated large liquid-propellant vehicle to various wind inputs is that the peaks of the load histories appear more strongly related to maximum wind shears than to maximum wind speed. For most vertically rising vehicles, the geographical loading variations can be best related to some combination of differences in both peak wind and shears.

Several important and practical observations are made as a mean for illustrating the findings of the study. For example, military and defense requirements placed on missiles dictate a specific type of wind environment for evaluation purposes, while optimization of space operations capability requires a very different wind environment for its supporting vehicles.

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Lee R. Hoxit and Robert M. Henry

Abstract

Rocketsonde temperature data taken during the period 1964–69 at White Sands, N. M., Cape Kennedy, Fla., and Wallops Island, Va., are stratified into 10 day and 10 night intervals and then averaged to give mean diurnal temperature curves at 5-km intervals from 30 to 60 km. Representative values of solar radiation errors are eliminated from all the daytime observations. The results show diurnal temperature ranges of 4.7, 3.6, 4.3, 8.9, 6.8, 7.2 and 8.9K at 30, 35, 40, 45,50, 55 and 60 km, respectively. The temperature maxima occur from 1–3 hr after local noon. The temperature minima occur 1–2 hr before sunrise below the stratopause and shortly after midnight above the stratopause.

Adjustments for systematic temperature errors and diurnal variations are applied to mean monthly temperatures (based on midday data only) to give estimates of the true monthly means. The January and July mean temperatures for the three stations are compared with the model atmospheres published in the U. S. Standard Atmosphere Supplements (1966).

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HENRY L. JACOBSON, ROBERT A. SANDERS, and DONALD M. HANSON

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No Abstract Available.

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William L. Smith, Wayne F. Feltz, Robert O. Knuteson, Henry E. Revercomb, Harold M. Woolf, and H. Ben Howell

Abstract

The surface-based Atmospheric Emitted Radiance Interferometer (AERI) is an important measurement component of the Department of Energy Atmospheric Radiation Measurement Program. The method used to retrieve temperature and moisture profiles of the plantetary boundary layer from the AERI’s downwelling spectral radiance observations is described.

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Wayne F. Feltz, William L. Smith, Robert O. Knuteson, Henry E. Revercomb, Harold M. Woolf, and H. Ben Howell

Abstract

The Atmospheric Emitted Radiance Interferometer (AERI) is a well-calibrated ground-based instrument that measures high-resolution atmospheric emitted radiances from the atmosphere. The spectral resolution of the instrument is better than one wavenumber between 3 and 18 μm within the infrared spectrum. The AERI instrument detects vertical and temporal changes of temperature and water vapor in the planetary boundary layer. Excellent agreement between radiosonde and AERI retrievals for a 6-month sample of coincident profiles is presented in this paper. In addition, a statistical seasonal analysis of retrieval and radiosonde differences is discussed. High temporal and moderate vertical resolution in the lowest 3 km of the atmosphere allows meteorologically important mesoscale features to be detected. AERI participation in the Department of Energy Atmospheric Radiation Measurement program at the Southern Great Plains Cloud and Radiation Testbed (SGP CART) has allowed development of a robust operational atmospheric temperature and water vapor retrieval algorithm in a dynamic meteorological environment near Lamont, Oklahoma. Operating in a continuous mode, AERI temperature and water vapor retrievals obtained through inversion of the infrared radiative transfer equation provide profiles of atmospheric state every 10 min to 3 km in clear sky or below cloud base. Boundary layer evolution, cold or warm frontal passages, drylines, and thunderstorm outflow boundaries are all recorded, offering important meteorological information. With important vertical thermodynamic information between radiosonde locations and launch times, AERI retrievals provide data for planetary boundary layer research, mesoscale model initialization, verification, and nowcasting. This paper discusses retrieval performance at the SGP CART site, as well as interesting meteorological case studies captured by AERI profiles. The AERI system represents an important new capability for operational weather- and airport-monitoring applications.

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Monsoon Region Climate Applications

Integrating Climate Science with Regional Planning and Policy

Andrea J. Ray, Gregg M. Garfin, Luis Brito-Castillo, Miguel Cortez-Vázquez, Henry F. Diaz, Jaime Garatuza-Payán, David Gochis, René Lobato-Sánchez, Robert Varady, and Chris Watts
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