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Murcray, D. G.

Publications and source records attributed to Murcray, D. G..

85 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS1979

SAGE ground truth plan: Correlative measurements for the Stratospheric Aerosol and Gas Experiment (SAGE) on the AEM-B satellite

The ground truth plan is outlined for correlative measurements to validate the Stratospheric Aerosol and Gas Experiment (SAGE) sensor data. SAGE will fly aboard the Applications Explorer Mission-B satellite scheduled for launch in early 1979 and measure stratospheric vertical profiles of aerosol, ozone, nitrogen dioxide, and molecular extinction between 79 N and 79 S. latitude. The plan gives details of the location and times for the simultaneous satellite/correlative measurements for the nominal launch time, the rationale and choice of the correlative sensors, their characteristics and expected accuracies, and the conversion of their data to extinction profiles. In addition, an overview of the SAGE expected instrument performance and data inversion results are presented. Various atmospheric models representative of stratospheric aerosols and ozone are used in the SAGE and correlative sensor analyses.

Russell, P. B.↗
NASA NTRS1979

Balloon-borne atmospheric spectral measurements

Infrared solar spectra, with .02 per cm resolution, were collected during sunset from a balloon at 40 km on October 27, 1978. Portions of the data obtained during the flight have been compared with theoretical calculations made using the data on the AFGL tape. The results of these comparisons reveal a number of areas of disagreement between theory and experimental results. The areas of disagreement are discussed in detail.

Murcray, D. G.↗
NASA NTRS1978

Identification of the nu-2 vibration-rotation band of ammonia in ground level solar spectra

Comparison of infrared solar spectra in the 750 to 950 kayser region obtained during sunrise and sunset shows that a number of features due to the nu-2 NH3 band are present on the sunset spectra but are indicated by only a trace on the sunrise spectra. The sunset path shows approximately 0.007 atm-cm NH3, and the reason for the discrepancy between sunrise and sunset spectra is not known. The ground-based measurements at Denver were obtained with a 0.06 kayser resolution.

Murcray, D. G.↗
NASA NTRS1978

Stratospheric NO and HNO3 observations in the Northern Hemisphere for three seasons

NO, HNO3, and O3 levels and air temperature were measured as a function of latitude in the 18 to 21 km region of the stratosphere, and the sum of odd nitrogen, equal to NO + NO2 + HNO3, was calculated and compared with model predictions. (NO2 values were inferred from photochemical equilibrium characteristics.) The data show that NO measurements generally exhibit good agreement with model predictions for low and midlatitudes but poor agreement at high latitudes. The experimental sum of odd nitrogen mixing ratios and model predictions agree within a factor of 2-1/2 or better at both 20 and 40 deg N, and show excellent agreement for latitudinal dependence.

Loewenstein, M.↗
NASA NTRS1978

Measurements of constituents of interest in the photochemistry of the ozone layer using infrared techniques

Infrared solar spectra and infrared atmospheric emission spectra were obtained from the ground, from aircraft and from balloons. The initial detection of most stratospheric molecules was achieved by the solar spectral technique because better resolution helps remove interference from other molecules. Because the sun is an intense source of radiation, the resolution which can be obtained with good signal-to-noise, is greater than with atmospheric emission spectroscopy. Data are generally taken using a method that enhances the number of molecules in the optical path i.e. at large solar zenith angles for solar spectra and at low elevation angles for atmospheric emission spectra. The search for molecules which are predicted to be present but which, the detection of a molecule known to be present from other measurement techniques but observed for the first time in infrared solar spectra, and some further data on the variability of HNO3 are discussed.

Murcray, D. G.↗
NASA NTRS1976

Remote sensing of trace constituents from atmospheric infrared emission and absorption spectra

Atmospheric infrared emission and absorption spectra obtained from aircraft and balloon-borne spectrometers are presented. From such spectra, mixing ratio vs altitude profiles are derived for several minor constituents. Recent results for HNO3, CF2Cl2, CFCl3, and HF are presented. In addition, the feasibility of infrared detection of other trace constituents, such as HCl, HF, NH3, NO and SO2, against the rest of the atmospheric background is studied. From this study, made on a line-by-line basis for 'state of the art' airborne spectrometers, potential spectral features for detection of the trace constituents are isolated.

Barker, D. B.↗
NASA NTRS1975

Detection of fluorocarbons in the stratosphere

Infrared absorption spectral measurements are applied to selected balloon flight data to detect CF2Cl2 and CFCl3 in the stratosphere. Identification of the fluorocarbons from absorption spectra is described, and the results are compared with previous models of fluorocarbon content at 21 km. A volume mixing ratio is derived for CF2Cl3 and a probable ratio is estimated for CFCl3. An upper limit for HF in the lower stratosphere up to 30 km is set based on data from a balloon flight.

Murcray, D. G.↗
NASA NTRS1975

Laboratory studies of infrared absorption by NO2 and HNO3

Data concerning the quantitative absorption in the 11 and 22 micron region by HNO3 were obtained. Results are presented indicating the temperature dependence of these bands of HNO3 vapor. The 21.8 micron absorption bands of HNO3 vapor at 40 C are discussed along with the integrated intensity and line parameters for the 6.2 micron band of NO2.

Murcray, D. G.↗
NASA NTRS1975

Absolute integrated intensity and individual line parameters for the 6.2-micron band of NO2

The absolute integrated intensity of the 6.2-micron band of NO2 at 40 C was determined from quantitative spectra at about 10 per cm resolution by the spectral band model technique. A value of 1430 plus or minus 300 per sq cm per atm was obtained. Individual line parameters, positions, intensities, and ground-state energies were derived, and line-by-line calculations were compared with the band model results and with the quantitative spectra obtained at about 0.5 per cm resolution.

Goldman, A.↗
NASA NTRS1975

Statistical-band-model analysis and integrated intensity for the 21.8 micrometer bands of HNO3 vapor

A large number of low-resolution quantitative spectra were obtained for a band-model analysis of 21.8-micrometer bands. The experimental investigations were conducted with pure nitric-acid vapor at 40 C, taking into account pressures in the range from a few torr to a pressure which is close to the saturation pressure. It is pointed out that the obtained data, in addition to those from the 11.3-micrometer band, can be used for an independent determination of the nitric acid vertical distribution in the stratosphere.

Goldman, A.↗
NASA NTRS1974

Measurements of trace constituents from atmospheric infrared emission and absorption spectra, a feasibility study

The feasibility of detecting eight trace constituents (CH4, HCl, HF, HNO3, NH3, NO, NO2 and SO2) against the rest of the atmospheric background at various altitudes from infrared emission and absorption atmospheric spectra was studied. Line-by-line calculations and observational data were used to establish features that can be observed in the atmospheric spectrum due to each trace constituent. Model calculations were made for experimental conditions which approximately represent state of the art emission and absorption spectrometers.

Goldman, A.↗