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Gille, J. C.

Publications and source records attributed to Gille, J. C..

At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1984

An overview of wave-mean flow interactions during the winter of 1978-79 derived from LIMS observations

Gradient winds, Eliassen-Palm (EP) fluxes and flux divergences, and the squared refractive index for planetary waves have been calculated from mapped data from the Limb Infrared Monitor of the Stratosphere (LIMS) experiment on Nimbus 7. The changes in the zonal mean atmospheric state, from early winter through 3 disturbances, is described. Convergence or divergence of the EP fluxes clearly produces changes in the zonal mean wind. The steering of the waves by the refractive index structure is not as clear on a daily basis.

Gille, J. C.↗
NASA NTRS1982

Workshop on Comparison of Data and Derived Dynamical Quantities During Northern Hemisphere (PMP-1) Winters

Atmospheric temperature and geopotential height were compared along with the quantities derived from them for application to stratospheric dynamics. The data for comparison were those gathered from radiosondes and rockets. Data from the Northern Hemisphere winters 1978/79 through 1981/82 were discussed, but most attention was devoted to days during the winter of 1978/79.

Gille, J. C.↗
NASA NTRS1982

Infrared limb scanning in the presence of horizontal temperature gradients - An operational approach

Simulation and analysis of IR limb radiance obtained by a satellite-borne IR limb scanner have demonstrated that horizontal temperature gradients in the atmosphere play an important role in limiting the accuracy of retrieved temperature and constituents below approximately 25 km. A simple operational approach to converting these observed radiances to equivalent spherical radiances is developed which preserves the advantages of the sphericity assumption in the inversion process.

Roewe, D. A.↗
NASA NTRS1982

Results from the LIMS experiment for the PMP-1 winter 1978/79

The results of a preliminary analysis of the data on the global distributions of temperature and trace constituents in the middle atmosphere (15-65 km) obtained with the limb IR monitor (LIMS) are presented. The 6-channel limb-scanning radiometer was sensitive to the 15 micron bands of CO2, as well as other wavelengths, and was launched on the Nimbus 7 satellite in 1978. The derived data were partially compared with Soviet rocketsonde data to track an evolution in a warming trend over Siberia. The morphology of the changes were attributed to stratospheric warming. The comparisons with rocketsonde data indicated that the LIMS data were suitable for the determination of planetary wave amplitudes and phases, heat and momentum transport, and Eliassen-Palm fluxes.

Gille, J. C.↗
NASA NTRS1982

The variability of stratospheric nitrogen compounds observed by LIMS in the winter of 1978-1979

The LIMS experiment was launched on the Nimbus 7 satellite for the purpose of sounding the vertical structure of temperature and key upper atmosphere trace gases on a global scale. The technique of thermal infrared limb sounding was used to obtain measurements of O3, H2O, NO2, and HNO3. LIMS collected data almost continuously from late October to late May over the latitude range from 64 deg S to 84 deg N. Two of the gases, NO2 and HNO3, are important elements in the NO(x) chain of chemical reactions leading to ozone destruction. Results for these gases are described in terms of zonal mean profiles and latitudinal distributions. The period selected for study is January-May 1979, when a major stratospheric warming occurred.

Russell, J. M., III↗
NASA NTRS1981

The Limb Infrared Monitor of the Stratosphere /LIMS/ experiment - Temperature and nitrogen dioxide results

The Limb Infrared Monitor of the Stratosphere (LIMS) is a satellite-borne radiometer which scans across the earth's limb, measuring infrared radiation emitted by specific atmospheric gases in a number of broad channels. Instrumentation includes a folded telescope, which focuses the radiation from the limb onto an array of six mercury-cadmium-telluride detectors. A scan mirror within the telescope sweeps the fields of view across the horizon, with each up or down scan lasting 12 seconds. The measurements are inverted to yield distributions of temperature and nitrogen dioxide. The temperature is determined from two channels covering the intervals 595-739 per cm and 645-673 per cm of the 15 micron bands of CO2, with maximum signal to noise ratio of 500-1000. Nitrogen dioxide is determined from measurements in a channel from 1580-1613 per cm, with an S/N of approximately 100. Results show that the LIMS temperature and nitrogen dioxide data are characterized by high precision.

Gille, J. C.↗
NASA NTRS1981

Satellite observations of upper atmosphere O3 and HNO3 from the Limb Infrared Monitor of the Stratosphere /LIMS/ experiment on Nimbus 7

The Limb Infrared Monitor of the Stratosphere (LIMS) experiment, launched on-board the Nimbus satellite, was designed to measure both day and night limb radiance which is used to infer upper atmosphere temperature profiles and chemical compound concentrations important in the study of ozone chemistry. The LIMS instrument is a six channel, limb scanning, thermal radiometer which uses HgCdTe detectors, cooled to approximately 64 K. Measurements include ozone, water vapor, nitrogen dioxide, and nitric acid. The ozone and nitric acid channels are centered at approximately 9.6 microns and 11.3 microns, respectively. Results from the channels are described with an emphasis on data validation. The O3 and HNO3 channels have demonstrated high measurement precision.

Russell, J. M., III↗
NASA NTRS1981

The validation of LIMS ozone profiles using correlative rocket, ECC, and Dobson data sets

The Limb Infrared Monitor of the Stratosphere (LIMS) experiment is a limb scanning infrared sounder designed to measure vertical temperature profiles and the concentrations of key chemical compounds which are important in the stratospheric ozone-nitrogen photochemistry. Preliminary ozone profiles are being intercompared with correlative rocket and balloonsonde ozone data sets as part of the Nimbus 7 LIMS data validation activity. The LIMS ozone retrievals extend from the lower mesosphere to the tropopause (or cloud-top altitudes). In this paper, preliminary statistics of comparisons of ECC (electrochemical concentration cell) ozonesonde and rocket ozone profiles with LIMS ozone profiles are presented. ECC ozonesonde data taken at times of LIMS overpasses are also used to extend the LIMS retrieval down to ground level. Each combined profile is then integrated to obtain total column ozone. These integrated results are compared to Dobson data obtained at approximately the same time and location.

Remsberg, E. E.↗
NASA NTRS1981

LRIR observations of diurnal ozone variation in the mesosphere

The Limb Radiance Inversion Radiometer (LRIR) on the Nimbus 6 spacecraft obtained measurements of atmospheric infrared emission from which vertical profiles of temperature and ozone mixing ratio can be deduced. A three day sequence of data on either side of the evening terminator has been analyzed as a function of solar zenith angle (35 deg to 105 deg) and pressure level (2 mb to .1 mb). The response of the ozone field to solar flux extinction, temperature variability, and nighttime recombination are readily detected.

Anderson, G. P.↗
NASA NTRS1981

Stratospheric water vapor results from the limb infrared monitor of the stratosphere /LIMS/ experiment on Nimbus 7

Stratospheric water vapor results taken from the limb infrared monitor of the stratosphere experiment on Nimbus 7 are presented with emphasis on validation studies. Basic radiance data, the indicated orbital precision of the experiment and comparisons made with data collected in simultaneous balloon underflights are described. A plot of pressure versus H2O channel radiance shows the radiance variability as a function of pressure and latitude. Measured precision is in good agreement with calculated values using simulations.

Russell, J. M., III↗
NASA NTRS1981

Observations of the interaction of ozone and dynamics

Data on the global distribution of temperature and ozone obtained with the Limb Radiance Inversion Radiometer which flew on the Nimbus 6 spacecraft are analyzed within the conceptual framework of Hartmann and Garcia (1979). The analysis supports the conclusion that ozone perturbations are dynamically controlled when the photochemical time constant is much greater than the dynamical time constant; when the photochemical constant is much less than the dynamical constant, ozone perturbations are photochemically controlled. It is also shown that the transports of planetary waves, or eddy transports, appear to be strongly localized in the region between the regimes in which dynamical and photochemical controls operate.

Gille, J. C.↗
NASA NTRS1980

Comparison of near coincident LRIR and OAO-3 measurements of equatorial night ozone profiles

The Limb Radiance Inversion Radiometer (LRIR), the infrared limb scanner on Nimbus 6, obtained equatorial night ozone profiles on 25 and 28 July, 1975, at nearly the same longitudes as the UV stellar occultation measurements made from the OAO-3 Copernicus observatory on 26 July, 1975. The LRIR determinations agree with many other data sources, but average roughly a factor of 3 lower than the Copernicus results. The LRIR results do not support the suggestion that there are serious gaps in understanding the chemistry of mesospheric ozone.

Gille, J. C.↗
NASA NTRS1980

Sounding the stratosphere and mesosphere by infrared limb scanning from space

Inversion of the measurements obtained by the infrared limb scanner on the Nimbus 6 satellite has demonstrated that the stratospheric and mesospheric temperatures and ozone concentrations may be obtained remotely from space with accuracy and precision comparable to in situ methods. Such global data have many applications in middle atmospheric research and operational temperature sounding.

Gille, J. C.↗
NASA NTRS1980

Temperature and composition measurements from the l.r.i.r. and l.i.m.s. experiments on Nimbus 6 and 7

The limb radiance inversion radiometer (LRIR) on Nimbus 6 was the first orbiting infrared limb scanner; it has four channels with which to determine temperature, O3, and H2O in the stratosphere and low mesosphere. The limb infrared monitor of the stratosphere (LIMS) is a similar six-channel instrument which was launched on Nimbus 7 in October 1978 in order to measure O3, H2O, NO2, and HNO3. The instrumentation and inversion techniques are briefly described, and the application of limb scanner data to the study of photochemical, dynamical, and transport problems is discussed.

Gille, J. C.↗
NASA NTRS1979

Middle atmosphere processes revealed by satellite observations

The present paper deals with satellite measurements carried out over the past decade, which include radiance measurements (closely associated with temperatures in the lower stratosphere), temperature measurements in the mesopause, and ozone distributions. Some information obtained from satellite data on chemical, dynamical, energy-balance, and transport processes is reviewed, and data suitable for testing dynamical and photochemical theories are noted.

Gille, J. C.↗