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At least 253 records · Page 14

Infrared remote sensing of the atmosphere of Venus from the Pioneer 12 Orbiter

The Pioneer 12 spacecraft, which was placed into orbit about Venus on 4 December 1978, carried a multispectral radiometer designed to investigate the structure and meteorological properties of the middle atmosphere (60 to 140 km). This paper reviews the experiment concept, the design, implementation and calibration of the hardware, and the preliminary scientific results from data obtained through 14 February 1979.

Taylor, F. W.↗

Development of data processing interpretation and analysis system for the remote sensing of trace atmospheric gas species

Problems associated with the development of the measurement of air pollution from satellites (MAPS) experiment program are addressed. The primary thrust of this research was the utilization of the MAPS experiment data in three application areas: low altitude aircraft flights (one to six km); mid altitude aircraft flights (eight to 12 km); and orbiting space platforms. Extensive research work in four major areas of data management was the framework for implementation of the MAPS experiment technique. These areas are: (1) data acquisition; (2) data processing, analysis and interpretation algorithms; (3) data display techniques; and (4) information production.

Casas, J. C.↗

Remote sensing of atmosphere-surface interaction parameters

Examples are given of the accuracy of the results obtained from the HIRS 2/MSU (High Resolution Infrared Sounder and Microwave Sounding Unit) analysis of ocean, atmosphere, and land parameters. Sea surface temperatures are compared with available ship and buoy radiosonde data, and land surface temperatures are compared with shelter temperatures. The seasonal change in land and ocean skin surface temperature is reviewed. The distribution of clouds is examined and their opacities in the visible and infrared parts of the spectrum are compared.

Chahine, M. T.↗

Multifrequency dial sensing of the atmospheric gaseous constituents using the first and second harmonics of a tunable CO2 laser radiation

The results of field measurements of concentration of some gaseous components of the atmosphere along the paths, in Sofia, Bulgaria, using a gas analyzer based on the use of a CO2 laser radiation frequency-doubled with ZnGeP2 monocrystals are presented. The gas analyzer is a traditional long path absorption meter. Radiation from the tunable CO2 laser of low pressure and from an additional He-Ne laser is directed to a colliminating hundredfold Gregori telescope with a 300 mm diameter of the principal mirror. The dimensions of the mirrors of a retroreflector 500 x 500 mm and a receiving telescope allow one to totally intercept the beam passed through the atmospheric layer under study and back.

Zuev, V. E.↗

Development of data processing, interpretation and analysis system for remote sensing of trace atmospheric gas species

Highly efficient methods were developed for the analysis and reduction of Measurement of Air Pollution from Satellite (MAPS) data. Specific attention was directed to analyzing the data from the Office of Space and Terrestrial Applications 3 (OSTA-3) correlative measurements of aircraft research flights and from the OSTA-3 shuttle flight. Methods were developed for error analysis of the aircraft and spacecraft instruments. The LSI 11/23 software system was modified and expanded for future data analysis.

Gormsen, B. B.↗

Remote sensing of the atmosphere of Mars using infrared pressure modulation and filter radiometry

The study of the atmosphere and climate of Mars will soon be advanced considerably by the Mars Observer mission. This paper describes the atmospheric sounder for this mission and how it will measure key Martian atmospheric parameters using IR gas correlation and filter radiometry. The instrument now under development will provide high-resolution vertical profiles of atmospheric temperature, pressure, water vapor, dust, and clouds using limb sounding techniques as well as nadir observations of surface thermal properties and polar radiative balance.

Mccleese, D. J.↗

Tunable solid-state lasers - An emerging technology for remote sensing of planetary atmospheres

The present development status and prospective (1990s) performance-improvement evaluation of tunable solid-state laser technology notes recent trends toward spectrum coverage over the 0.20-14.0 microns range, in addition to dramatic increases in efficiency, service life, and reliability. It is judged that the Ti:Al2O3 laser and the AgGaSe2 optical parametric oscillator pumped by a Ho:YAG laser could cover the near-IR and mid-IR regions of the spectrum. Laser diodes operating at 0.78 microns should provide an excellent pump for a Ho:YAG laser.

Barnes, Norman P.↗

Passive microwave sensing of the atmosphere

The development of microwave instrumetns to sound the atmosphere is reveiwed, focusing on the Advanced Microwave Sounding Unit (AMSU). The AMSU is planned for operation in a geosynchronous orbit or in LEO near 118 GHz. The three main AMSU subsystems are described: a 15-channel temperature sounder with a 50-km resolution, a 5-channel atmospheric moisture sounder with a 15-km resolution, and a 7-channel stratospheric and mesospheric temperature sounder with 150-km resolution. In addition, the potential for limb-sounding instruments is considered.

Staelin, David H.↗

Remote sensing of the atmosphere by multi-channel radiometers

To characterize Earth/space communication links, the Jet Propulsion Laboratory's (JPL's) Radiowave Propagation Program supports a number of propagation studies. Low-availability satellite links and their propagation vagaries at Ka and millimeter-wave bands constitute a major effort within this program. Since 1987, this program has funded the Wave Propagation Laboratory (WPL) of the National Oceanic and Atmospheric Administration (NOAA) to conduct multiple-frequency radiometric observations of the atmosphere. Measurements of atmospheric emission and attenuation at 20, 31, and 90 GHz at different locations are presented. Single-station and joint-station statistics are derived. A linear regression scheme for the prediction of fade statistics in one channel using fade data from the other two channels is presented.

Davarian, Faramaz↗

Efficiencies of Rotational Raman, and Rayleigh Techniques for Laser Remote Sensing of the Atmospheric Temperature

Various lidar methods have been developed for measuring the atmospheric temperature, making use of the temperature dependant characteristics of rotational Raman scattering (RRS) from nitrogen and oxygen, and Rayleigh or Rayleigh-Brillowin scattering (RS or RBS). These methods have various advantages and disadvantages as compared to each other but their potential accuracies are principal characteristics of their efficiency. No systematic attempt has been undertaken so far to compare the efficiences, in the above meaning, of different temperature lidar methods. Two RRS techniques have been compared. Here, we do such a comparison using two methods based on the detection and analysis of RS (RBS) spectra. Four methods are considered here for measuring the atmospheric temperature. One of them (Schwiesow and Lading, 1981) is based on an analysis of the RS linewidth with two Michelson interferometers (MI) in parallel. The second method (Shimisu et al., 1986) employs a high-resolution analysis of the RBS line shape. The third method (Cooney, 1972) employs the temperature dependance of the RRS spectrum envelope. The fourth method (Armstrong, 1974) makes use of a scanning Fabry-Perot interferometer (FPI) as a comb filter for processing the periodic RRS spectrum of the nitrogen. Let us denote the corresponding errors in measuring the temperature by sigma(sub MI), sigma(sub HR), sigma(sub ENV), and sigma(sub FPI). Let us also define the ratios chi(sub 1) = sigma(sub MI)/sigma(sub ENV), chi(sub 2) = sigma(sub HR)/sigma(sub ENV), and chi(sub 3) = sigma(sub FPI)/sigma(sub ENV) interpreted as relative errors with respect to sigma(sub ENV).

Ivanova, I. D.↗

Development of a Ti:Al2O3 Laser for Remote Sensing of the Atmosphere

During the past year, the following research has been conducted on the Titanium Sapphire Laser system development project: (1) Characterization of the laser system; (2) Gain measurement; (3) Second and third harmonic generation; (4) Laser temporal characteristics; and (5) Laser modeling. Figures and descriptions of the topics above are presented.

Elsayed-Ali, Hani↗

Jupiter: Atmospheric Sounding and Sensing of the Interior (JASSI)

The formation of the giant planets is one of the most fundamental questions in solar system exploration. Understanding the process that led to the creation of Jupiter is essential to understanding the nature of the primordial solar nebula, and the formation of our solar system and others currently being discovered. Data from Galileo combined with HST and Ulysses results validated our basic understanding of Jupiter as a giant planet whose gaseous envelope consists of solar nebula gas enriched in elements heavier than He by in falling icy planetesimals. However, the current Galileo Probe data set does not itself allow firm conclusions about the original planetesimal composition or the process of giant planet formation - we crucially need the O and N abundances that Galileo could not determine. We propose a new and simple concept capable of determining these abundance in Jupiter plus substantial gravity science. Additional information is contained in the original extended abstract.

Bolton, S. J.↗

Ground Based Remote Sensing of Upper Atmosphere Dynamics, Thermodynamics and Composition in Support of TIMED Satellites Scientific Mission

The following research work was accomplished: 1. We operated high throughput spectrophotometers and interferometers at eight observatories in the Arctic, Antarctic and mid-latitude regions to record relatively high-resolution spectra of very low light level airglow and auroral line as well as band emissions. 2. Our Polar observations of auroral emissions from N2 and O emissions have been analyzed to derive the O/N2 ratios around 110 km height in the Polar thermosphere during different auroral events triggered by the precipitation of auroral electrons with average energy of about 10 keV. These results have been compared with similar ratios derived from TIMED satellite s GUVI measurements of N2 LBH and 01 1356A emissions. 3. Our airglow measurements show MLT density and temperature modulations by Planetary, Tidal and Gravity Waves. They also indicate Mesopause cooling preceding a Stratospheric Warming Event (SWE).

Source record↗

The Atmospheric Infrared Sounder (AIRS) on the NASA Aqua Spacecraft: A General Remote Sensing Tool for Understanding Atmospheric Structure, Dynamics and Composition

The Atmospheric Infrared Sounder (AIRS) on the EOS Aqua Spacecraft was launched on May 4, 2002. Early in the mission, the AIRS instrument demonstrated its value to the weather forecasting community with better than 6 hours of improvement on the 5 day forecast. Now with over eight years of consistent and stable data from AIRS, scientists are able to examine processes governing weather and climate and look at seasonal and interannual trends from the AIRSdata with high statistical confidence. Naturally, long-term climate trends require a longer data set, but indications are that the Aqua spacecraft and the AIRS instrument should last beyond 2018. This paper briefly describes the AIRS data products and presents some of the most significant findings involving the use of AIRS data in the areas of weather forecast improvement, climate processes and model validation, cloud and polar processes, and atmospheric composition (chemistry and dust).

Temperature↗