New features of global climatology revealed by satellite-derived oceanic rainfall maps

Quantitative rainfall maps over the oceanic areas of the globe were derived from the Nimbus 5 Electrically Scanning Microwave Radiometer (ESMR) data. Analysis of satellite derived oceanic rainfall maps reveal certain distinctive characteristics of global patterns for the years 1973-74. The main ones are (1) the forking of the Intertropical Convergence Zone in the Pacific, (2) a previously unrecognized rain area in the South Atlantic, (3) the bimodal behavior of rainbelts in the Indian Ocean and (4) the large interannual variability in oceanic rainfall. These features are discussed

Periodic variations of precipitation in the tropical Atlantic Ocean

Statistical analysis of the satellite-borne Electrically Scanning Microwave Radiometer data in the tropical Atlantic region reveals that the rainfall near local noon is higher both in frequency of occurrence and intensity than the rainfall in the same area near local midnight. Another striking feature that stands out from the analysis is an oscillation with a period of 3.3. days in rainfall occurrence and intensity. This periodicty is consistent with easterly waves traveling from the African continent to the region under study

Vertical temperature and density patterns in the Arctic mesosphere analyzed as gravity waves

Rocket soundings conducted from high latitude sites in the Arctic mesosphere are described. Temperature and wind profiles and one density profile were observed independently to obtain the thermodynamic structure, the wind structure, and their interdependence in the mesosphere. Temperature profiles from all soundings were averaged, and a smooth curve (or series of smooth curves) drawn through the points. A hydrostatic atmosphere based on the average, measured temperature profile was computed, and deviations from the mean atmosphere were analyzed in terms of gravity wave theory. The vertical wavelengths of the deviations were 10-20 km, and the wave amplitudes slowly increased with height. The experimental data were matched by calculated gravity waves having a period of 15-20 minutes and a horizontal wavelength of 60-80 km. The wind measurements are consistent with the thermodynamic measurements. The results also suggest that gravity waves travel from East to West with a horizontal phase velocity of approximately 60 m sec-1

Seasonal transitions in the thermal structure of the mesosphere at high latitudes

Acoustic grenade experiments to monitor transition in thermal structure of mesospher

Measurements of the structure and circulation of the stratosphere and mesosphere, 1971-2

Complete data from a total of 43 meteorological rocket soundings of the stratosphere and mesosphere conducted from Barrow, Alaska; Churchill, Canada; Wallops Island Va.; and Kourou, French Guiana are presented. These data consist of temperature, pressure, density, and wind profiles from 35 acoustic grenade soundings that cover the 30 to 90 km altitude range, and temperature, pressure, and density profiles from 8 pitot probe soundings that cover the 25 to 120 km altitude range. Errors for each of the 35 acoustic grenade soundings are also included

Spacelab 3: Research in microgravity

The Spacelab 3 mission, which focused on research in microgravity, took place during the period April 29 through May 6, 1985. Spacelab 3 was the second flight of the National Aeronautics and Space Administration's modular Shuttle-borne research facility. An overview of the mission is presented. Preliminary scientific results from the mission were presented by investigators at a symposium held at Marshall Space Flight Center on December 4, 1985. This special issue is based on reports presented at that symposium

The mean observed meteorological structure and circulation of the stratosphere and mesosphere

Meteorological soundings of the upper stratosphere and mesosphere, conducted with in situ rocket techniques during all seasons of the year from several sites, ranging in latitude from 8 deg S to 71 deg N, are analyzed. The resulting data are compiled into mean monthly and seasonal profiles of temperature, pressure, density, and wind for each site and are presented in graphical and tabular form. Analyses of these mean values produced time cross sections, quasi-meridional cross sections, and constant level maps which are included

The effects of orography on land-atmosphere turbulent exchange processes

An experimental investigation of the effects of orography on the boundary layer was conducted in February 1984 in the vicinity of Boulder, Colorado. Wind and thermodynamic data were acquired principally by the NASA B57-B aircraft but also with rawinsondes, the Boulder Atmospheric Observatory meteorological tower, the PROFS Mesonet surface stations, the radar wind profiler network, and the Boulder wind network. The aircraft, which was instrumented to measure 3-axis mean winds and turbulence fluctuations as well as temperature and moisture information, was flown in a box-like pattern at multiple levels from approximately 305 m (1000 ft) to 3140 m (10,300 ft) above the surface. These data provided a three-dimensional view of the flow in the lee of the Rocky Mountains, including the front range, the Flat Irons. The data acquired revealed the nature of the flow with varying directions of the prevailing wind relative to the mountain range. Profiles of momentum flux, heat flux, and turbulence kinetic energy were calculated and analyzed. Consistent patterns emerged in the flow. Separation of the flow from the sharp edges of orographic features were detected. Indication of flow reattachment and even reverse flows on the plain downstream of the mountain range were evident. Monin-Obukhov lengths calculated from tower and aircraft for two days indicating that the day February 1, 1984, with flow normal to the mountain range was highly stable whereas the day February 2, 1984, was moderately unstable in the surface layer. TV Comparison of the data with parameterization models for general circulation numerical schemes is given. The results suggest strong orographic effects. Values of the universal similarity function of Yamada were calculated from the observations and compared with the theory. Discrepancies were found which were also attributed to unusual flow caused by the orographic features

Response of the neutral particle upper atmosphere to the solar eclipse of 7 March 1970

A series of five pitot probes were launched from Wallops Island, Va. (38[deg]N) in conjunction with the solar eclipse, 7 March 1970. Three soundings were programmed to occur at 40, 80 and 100 per cent obscuration of the Sun (at 100 km) during a 42-min period. The remaining two soundings were made 24 hr before and after the eclipse. The five soundings yielded neutral particle pressure, temperature, and density profiles over the altitude regime 30-125 km. Below 95 km the three density profiles resulting from the eclipse day launches had an average deviation of less than 1.5 per cent. Above 95 km density changes of up to 20 per cent were observed. Such changes in density are comparable in magnitude to those normally observed over a period of several hours. On 10 March 1971, three additional pitot probes were launched from Wallops Island, Va. at times identical to those of the 1970 eclipse day. Comparison of the two sets of data should provide for a more objective analysis regarding atmospheric response to solar input.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34130/1/0000414.pd

Enhanced Damage-Resistant Optics for Spaceflight Laser Systems: Workshop findings and recommendations

NASA has defined a program to address critical laser-induced damage issues peculiar to its remote sensing systems. The Langley Research Center (LaRC), with input from the Goddard Space Flight Center (GSFC), has developed a program plan focusing on the certification of optical materials for spaceflight applications and the development of techniques to determine the reliability of such materials under extended laser exposures. This plan involves cooperative efforts between NASA and optics manufacturers to quantify the performance of optical materials for NASA systems and to ensure NASA's continued application of the highest quality optics possible for enhanced system reliability. A review panel was organized to assess NASA's optical damage concerns and to evaluate the effectiveness of the LaRC proposed program plan. This panel consisted of experts in the areas of laser-induced damage, optical coating manufacture, and the design and development of laser systems for space. The panel was presented information on NASA's current and planned laser remote sensing programs, laser-induced damage problems already encountered in NASA systems, and the proposed program plan to address these issues. Additionally, technical presentations were made on the state of the art in damage mechanisms, optical materials testing, and issues of coating manufacture germane to laser damage