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Mccleese, Daniel J.

Publications and source records attributed to Mccleese, Daniel J..

Mars Observer: Applications to atmospheric transport

The Pressure Modulator Infrared Radiometer (PMIRR) is an atmospheric sounder designed to observe temporal and spatial variations of water vapor and of dust suspended in the Mars atmosphere, to characterize the planetary-scale thermal structure and circulation of the atmosphere, and to quantify the polar radiative balance. These measurements are fundamental to understanding the seasonal cycles of dust, of water, and of CO2 on Mars and, in particular, to determining the role of atmospheric transport. Using measurements in eight narrow-band infrared spectral regions and one broadband visible channel, the PMIRR investigation teams at JPL and Oxford University will derive vertical profiles of atmospheric temperature, extinction due to suspended dust, and water vapor concentration, as well as locations of CO2 and H2O ice clouds. These data will be used in a variety of ways to address issues of atmospheric dynamics and transport. Three topics will be emphasized here: (1) the expected precision of the retrieved profiles of temperature, dust extinction, and water vapor, including plans for validating the profiles; (2) the observation strategy, designed to best use PMIRR's two-axis scan mirror, as deployed in the Mars Observer mapping orbit; and (3) approaches to mapping the atmospheric fields globally and the derivation of key meteorological fields related to estimating atmospheric transport.

Zurek, Richard W.

Stratospheric Wind Infrared Limb Sounder

The Stratospheric Wind Infrared Limb Sounder (SWIRLS), which measures wind, temperature, and the abundance of O3 and N2O in the stratosphere from earth orbit is selected as one of the complement of atmospheric sounders that will fly on the Earth Observing System B platform series. This paper outlines the SWIRLS investigation and describes laboratory experiments demonstrating SWIRLS wind measurement capabilities.

Rider, David M.

Diagnosis Of A Pressure-Modulator-Radiometer Cell

Spectral response of pressure-modulator-radiometer cell measured with help of lead-salt tunable diode laser. Laser chosen because of narrow bandwidths {2 x 10 to negative 4th power (cm) to negative 1st power} and relatively high powers (up to 1 mW continuous) of such lasers and because available for wavelengths from 3 to 30 micrometers. Direct measurement of spectral response enables formulation of more-precise atmospheric-transmission functions, enabling extraction of better information from readings taken with instrument.

May, Randy D.

Survey Of Gas-Correlation Spectroradiometry

Principle application is remote sensing of atmospheres. Report discusses use of gas-correlation spectroradiometry in remote measurements of atmosphere of Earth and other planets. Summarizes history of technique from first such instrument flown aboard Nimbus 4 Satellite in 1970 to one that is to fly on Mars Observer Spacecraft to measure vertical distribution of water vapor and temperature. On Earth technique applied mostly to upper atmosphere and only infrequently to troposphere, where pressure broadening tends to blend spectral lines.

Mccleese, Daniel J.

Two-Frequency Electro-Optic Gas-Correlation Spectrometer

Acoustical modulator not necessary. Two-frequency electro-optic gas-correlation spectrometer relatively simple. Illumination provided by ordinary lamp, no moving parts, and filtered output of detector is beat-frequency signal directly proportional to correlation between spectra of gases in cells.

Margolis, Jack S.

Phase-Modulation Gas-Correlation Spectroscopy

Electro-optic phase-modulation gas-correlation spectroscopy demonstrated in laboratory tests promising candidate technique for remote sensing of gases, temperatures, and wind velocities in atmosphere. In technique radiation emitted by sample atmosphere passed through electro-optic phase modulator, and modulated and unmodulated versions of spectrum alternately passed through reference absorption cell containing gas to be detected. Radiation emerging from reference cell band-pass filtered and detected. Correlation signal is difference in intensity between phase-modulated and unmodulated detected signals.

Rider, David M.

Tunable diode laser spectral diagnostic studies of a pressure modulator radiometer

The successful application of high-resolution tunable diode laser spectroscopy to the diagnostic measurement of a pressure modulator radiometer (PMR) is reported, and recorded line transmission profiles for a single N2O line at 1272/cm are presented. PMR measurements obtained for mean cell pressures of about 10, 20, and 30 Torr were found to be consistent with theoretical predictions. The validity of single-pressure and two-pressure approximation representations of the mean and modulated PMR transmission spectra has been verified.

May, Randy D.

Flux of water vapor in the terrestrial stratosphere and in the Martian atmosphere

A summary of the terrestrial satellite data is presented. The observations indicate that at equatorial latitudes, relatively dry air is introduced at the tropopause and carried to the upper stratosphere. At that altitude, any methane present in the ascending air mass is oxidized photochemically into water vapor. This vapor is eventually transported to high latitudes, where it is carried to the lower stratosphere by the descending leg of the diabatic circulation. The Pressure Modulator Infrared Radiometer instrument aboard the Mars Observer should provide a comparable picture of vapor transport in the martian atmosphere.

Leovy, Conway

Measurements of the vertical profile of water vapor abundance in the Martian atmosphere from Mars Observer

An analysis is presented of the Pressure Modulator Infrared Radiometer (PMIRR) capabilities along with how the vertical profiles of water vapor will be obtained. The PMIRR will employ filter and pressure modulation radiometry using nine spectral channels, in both limb scanning and nadir sounding modes, to obtain daily, global maps of temperature, dust extinction, condensate extinction, and water vapor mixing ratio profiles as a function of pressure to half scale height or 5 km vertical resolution. Surface thermal properties will also be mapped, and the polar radiactive balance will be monitored.

Schofield, J. T.

Passive remote sensing of stratospheric and mesospheric winds

A passive infrared sensor is described for remote sounding of the wind field in the stratosphere and mesosphere from near Earth orbital spacecraft. The instrument uses gas correlation spectroscopy together with electro-optic phase modulation techniques to measure winds in the 20- to 120-km altitude range globally, both in the day and at night, and with a vertical resolution of better than the atmospheric scale height. Measurement of temperature and the amounts of key atmospheric species may also be made simultaneously and in coincident fields of view with the wind observations. The sensor is currently being developed at the Jet Propulsion Laboratory as a candidate for the upcoming NASA Earth Observation System.

Mccleese, Daniel J.