The Hydrogen Budget of the Stratosphere Inferred from ATMOS Measurements of H20 and CH4
Explore the source record for details and available documents.
Engineering topics
Publications and source records attributed to Rinsland, C. P..
Explore the source record for details and available documents.
The ATMOS Fourier transform spectrometer was flown for a fourth time on the Space Shuttle as part of the ATLAS-3 instrument payload in November 1994. More than 190 sunrise and sunset occultation events provided measurements of more than 30 atmospheric trace gases at latitudes 3-49N and 65-72S, including observations both inside and outside the Antarctic polar vortex.
We compare the mixing rations of N 2 O, CFC-11, CFC-12, CCI 4 , SF 6 , and HCI in the mid-latitude stratosphere measured by the ATMOS Fourier transform spectrometer with in situ measurements acquired aboard the NASA ER-2 aircraft during November 1994. Good agreement is found between ATMOS and in situ correlations of CFC-11, CFC-12, and SF 6 with N 2 O. ATMOS observations of CCI 4 are approx. 15 percent higher than the ER-2 data, but within the systematic uncertainties.
We have compared volume mixing ration profiles of N 2 O, CFC-11, CFC-12, CCI 4 , SF 6 , and HCI measured for the mid-latitude stratosphere by the ATMOS Fourier transform spectrometer during the ATLAS-3 Space Shuttle mission of NOvember 1994 with in situ measurements acquired aboard the NASA ER-2 aircraft during the same time period.
...Descent rates for atmospheric inferred from ATMOS (Atmospheric Trace Molecule Spectroscopy)tracer observations agree well with theoretical estimates obtained using radiative heating calculations...
Numerous absoption lines of stratospheric sulfer dioxide (SO2) were identified in solar occulation spectra recorded by the Atmospheric Trace Molecule Spectroscopy (ATMOS) Fourier transform spectrometer during the Atmospheric Laboratory for Applications and Science (ATLAS)-1 shuttle mission (March 24-April 2, 1992). based on their analysis, a volume mixing ratio profile of SO2 increasing from (13 +/- 4) p.p.t.v. (parts per 10(exp -12) by volume) at 16 mbar (approximately 28 km) to 455 +/- 90 p.p.t.v. at 0.63 mbar (approximately 52 km) was measured with no significant profile differences between 20 deg N and 60 deg S latitude. The increase in the SO2 mixing ratios with altitude indicates the presence of a source of SO2 in the upper stratosphere. Profiles retrieved from ATMOS spectra recorded during shuttle flights in April-May 1985 and April 1993 show similar vertical distributions but lower concentrations. Two-dimensional model calculations with SO2 assumed as the end product of H2SO4 photolysis produce SO2 profiles consistent with the ATMOS measuremnts to within about a factor 2.
Explore the source record for details and available documents.
A simple, classical, and expedient method for the retrieval of atmospheric pressure-temperature profiles has been applied to the high-resolution infrared solar absorption spectra obtained with the atmospheric trace molecule spectroscopy (ATMOS) instrument. The basis for this method is a rotational analysis of retrieved apparent abundances from CO2 rovibrational absorption lines, employing existing constituent concentration retrieval software used in the analysis of data returned by ATMOS. Pressure-temperature profiles derived from spectra acquired during the ATLAS 1 space shuttle mission of March-April 1992 are quantitatively evaluated and compared with climatological and meteorological data as a means of assessing the validity of this approach.
Stratospheric ozone measurements made by the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment from onboard the Space Shuttle during the period 8-16 April 1992 are compared with other space-based remote sensing measurements.
A method to retrieve elements of the carbon monoxide (CO) vertical distribution from ground-based high-resolution infrared solar spectra has been developed. The method is based on the fact that the total column amount retrieved by nonlinear least squares spectral fitting techniques depends on the shape of the assumed a priori profile and this dependence is a function of the absorption line intensity and the lower state energy of the transition. Four CO lines between 2057 and 2159/cm have been selected and the method has been tested on synthetic spectra. The CO total column content and average concentrations in two atmospheric layers (surface to 400 mbar and 400 mbar to the top of the atmosphere) can be retrieved with precisions of about 1% and less than 10%, respectively. Solar spectra recorded at Kitt Peak from 1982 to 1993 have been analyzed. The CO total column and the average concentration in the two layers show an asymmetrical seasonal cycle with extreme values of (1.1-2.1) x 10(exp 18) molecules cm(exp -2), (50-80) parts per billion by volume (ppbv) in the top layer and (80-160) ppbv in the bottom layer, and precisions of 1, 3, and 6%, respectively; a spring maximum and late summer minimum are observed.
A practical procedure for the retrieval of ozone vertical profiles from ground-based high resolution Fourier transform infrared solar spectra has been developed. The analysis is based on a multilayer line-by-line forward model and a semi-empirical version of the optimal estimation inversion method of Rodgers. The 1002.6-1003.2 cm(exp -1) spectral interval has been selected for the analysis on the basis of synthetic spectrum calculations. This interval contains numerous ozone lines covering a range of intensities and providing retrieval sensitivity from ground level to about 35 km. Characterization of the method and an error analysis have been performed. For a spectral resolution of 0.05-0.01 cm(exp -1) and a signal-to-noise ratio greater than or equal to 100 the retrieval is stable with a vertical resolution of approximately 5 km attainable near the surface degrading to approximately 10 km in the stratosphere. Synthetic spectra studies show that the a priori profile and weak constraints selected for the retrievals introduce no significant biases for a wide range of ozone profiles.
Measurements of stratospheric ozone were made by the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment from onboard the Space Shuttle during the period 8-16 April 1992. The precision and accuracy of the measurements are discussed in the context of establishing the accuracy and compatibility of the measurements relative to other space-based measurements of ozone. Coincident measurements were obtained from the Stratospheric Aerosol and Gas Experiment (SAGE) 2 instrument onboard the Earth Radiation Budget Satellite (ERBS) and three instruments, the Microwave Limb Sounder (MLS), the Cryogenic Limb Array Etalon Spectrometer (CLAES), the Halogen Occultation Experiment (HALOE) onboard the Upper Atmospheric Research Satellite (UARS). Three of the instruments, ATMOS, SAGE-2 and MLS are demonstrated to be consistent to within +10% over the altitude range between 100 hPa and 0.5 hPa (approximately 20 to 60 km), with ATMOS and MLS displaying a zero mean bias and a root mean square deviation (rms) of 3% and SAGE-2 displaying an essentially systematic bias of -5% over the majority of the altitude range, except for below 30 hPa where SAGE-2 displays a large positive systematic bias due to the effect of the aerosol attenuation resulting from the Mt. Pinatubo volcanic eruption in 1991. The comparison with HALOE indicates that ozone levels observed by ATMOS are systematically higher than HALOE by 5 to 25% with a clear gradient in the differences; in contrast the comparison with CLAES displays differences of as much as + 30% with no obvious systematic scaling possible. Comparisons are evaluated in two separate schemes, by geographical coincidence and through zonal averages which illustrate the limitations of both schemes. Latitudinal and longitudinal variation are used to assess the sensitivity of the ATMOS measurements and to confirm the precision and accuracy, which should be less than 4% and 10% respectively.
The Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment uses a Fourier transform spectrometer on board the space shuttle to record infrared solar occultation spectra of the atmosphere. Described are the current version of the molecular spectroscopic database used for the analysis of the data obtained during three Space Shuttle missions between 1992 and 1994.
Vertical enrichment profiles of stratospheric ozone with oxygen 18 in the second or third position have been derived from space- based solar occultation spectra recorded at 0.01/cm resolution with the ATMOS (Atmospheric Trace Molecule Spectroscopy) Fourier- transform infrared (FTIR) spectrometer.
Quantitative measurements of the wavelength dependence of aerosol extinction in the 750-3400/cm spectral region have been derived from 0.01/cm resolution stratospheric solar occultation spectra recorded by the ATMOS (Atmospheric Trace Molecule Spectroscopy) Fourier transform spectrometer about 9 1/2 months after the Mt Pinatubo volcanic eruption. Strong, broad aerosol features have been identified near 900, 1060, 1190, 1720, and 2900/cm below a tangent height of approximately 30 km. Aerosol extinction measurements derived from approximately 0.05/cm wide microwindows nearly free of telluric line absorption in the ATMOS spectra are compared with transmission calculations derived from aerosol size distribution profiles retrieved from correlative SAGE (Stratospheric Aerosol and Gas Experiment) II visible and near i.r. extinction measurements, seasonal and zonally averaged H2SO4 aerosol weight percentage profiles, and published sulfuric acid optical constants derived from room temperature laboratory measurements. The calculated shapes and positions of the aerosol features are generally consistent with the observations, thereby confirming that the aerosols are predominantly concentrated H2SO4-H2O droplets, but there are significant differences between the measured and calculated wavelength dependences of the aerosol extinction. We attribute these differences as primarily the result of errors in the calculated low temperature H2SO4-H2O optical constants. Errors in both the published room temperature optical constants and the limitations of the Lorentz-Lorenz relation are likely to be important.
About 200 i.r. solar spectra recorded at 0.01/cm resolution on 71 days between November 1991 and July 1993 at the Network for the Detection of Stratospheric Change (NDSC) station at Mauna Loa, Hawaii (latitude 19.53 deg N, longitude 155.58 deg W, elevation 3.459 km) have been analyzed with a nonlinear least-squares spectral fitting technique to study temporal variations in the total column of atmospheric ethane (C2H6) above the site. The results were derived from the analysis of the unresolved nu(sub 7) band (P)Q(sub 3) subbranch at 2976.8/cm. A distinct seasonal cycle is observed with a factor of 2 variation, a maximum total column of 1.16 x 10(exp 16) mol/sq cm at the end of winter, and a minimum total column of 0.53 x 10(exp 16) mol/sq cm at the end of summer. Our measurements are compared with previous observations and model predictions.