References of "Zander, Rodolphe"
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See detailCorrelation relationships of stratospheric molecular constituents from high spectral resolution, ground-based infrared solar absorption spectra
Rinsland, C. P.; Goldman, A.; Connor, B. J. et al

in Journal of Geophysical Research. Atmospheres (2000), 105(D11), 14637-14652

Comparisons of chemically active species with chemically inert tracers are useful to quantify transport and mixing and assess the accuracy of model predictions. We report measurements of chemically active ... [more ▼]

Comparisons of chemically active species with chemically inert tracers are useful to quantify transport and mixing and assess the accuracy of model predictions. We report measurements of chemically active species and chemically inert tracers in the stratosphere derived from the analysis of infrared solar absorption spectra recorded with a ground-based Fourier transform spectrometer operated typically at 0.005- to 0.01-cm(-1) spectral resolution. The measurements were recorded from Kitt Peak in southern Arizona (latitude 31.9 degrees N, 111.6 degrees W, 2.09 km altitude). Time series of N2O, CH4, O3, and HNO3 vertical profiles have been retrieved from measurements in microwindows. From these results, correlations between N2O and CH4 stratospheric mixing ratios and between O3 and HNO3 lower stratospheric mixing ratios have been derived. The measured correlations between N2O versus CH4 mixing ratios are compact and show little variability with respect to season in quantitative agreement with Atmospheric Trace Molecule Spectroscopy Experiment (ATMOS) spring and autumn measurements recorded near the same latitude. Lower stratospheric O3 versus HNO3 mixing ratios measured during low to moderate aerosol loading time periods also show a compact relations though the HNO3/O3 slope is a factor of 2 lower than obtained from November 1994 ATMOS measurements near the Same latitude. We also compare Kitt Peak and ATMOS N2O versus CH4 and O3 versus HNO3 relations obtained by averaging the measurements over two broad stratospheric layers. This comparison avoids bias from the a priori profiles and the limited vertical resolution of the ground-based observations. [less ▲]

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See detailStratospheric CO at tropical and mid-latitudes: ATMOS measurements and photochemical steady-state model calculations
Rinsland, C. P.; Salawitch, R. J.; Osterman, G. B. et al

in Geophysical Research Letters (2000), 27(9), 1395-1398

We characterize the spring and fall stratospheric distribution of CO at 49 degrees N-55 degrees S latitude from ATMOS profiles measured during 4 shuttle flights, Measured mixing ratios increase with ... [more ▼]

We characterize the spring and fall stratospheric distribution of CO at 49 degrees N-55 degrees S latitude from ATMOS profiles measured during 4 shuttle flights, Measured mixing ratios increase with potential temperature (theta) from 12 ppbv (10(-9) per unit volume) at 525 K, to 30-40 ppbv at 1750 K with only minor variations with latitude and season at a theta level. Evidence for some confinement near 1150 K in the developing November 1994 vortex is indicated from comparison of CO and N2O horizontal gradients. Measured CO mixing ratios at the tropical tropopause are a factor of 10 higher than values calculated with a steady-state model using standard photochemistry constrained by correlative temperatures and pressures, and ATMOS measurements including CH4 as inputs, Differences decrease with latitude at constant theta and are <20% at 800 K and all latitudes, where the CO photochemical lifetime is 40-50 days. [less ▲]

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See detailMonitoring the stratospheric chlorine budget during the past decades: the Montreal Protocol at work
Mahieu, Emmanuel ULg; Zander, Rodolphe ULg; Mélen, Francine et al

in NASDA (Ed.) Proceedings of the Quadriennal ozone symposium - Sapporo 2000 (2000)

The study of series of ground-based solar observations performed within the frame of the NDSC indicates that the rate of increase of the atmospheric loading of inorganic chlorine has progressively slowed ... [more ▼]

The study of series of ground-based solar observations performed within the frame of the NDSC indicates that the rate of increase of the atmospheric loading of inorganic chlorine has progressively slowed down, then stabilized around 1996-97, with a subsequent tendency towards a decrease. The investigation is based on total column abundances of HCl and ClONO2 measured at the Jungfraujoch station in the Swiss Alps and on stratospheric columns of HCl derived from observations at Kitt Peak National Observatory (Arizona, USA). The observed changes are compared with near-global observations of HCl around the stratopause by HALOE and with a global, best-case emission scenario of Cl-bearing ground-level source gases compiled by UNEP [less ▲]

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See detailFifteen years-trend characteristics of key stratospheric constituents monitored by FTIR above the Jungfraujoch.
Mahieu, Emmanuel ULg; Zander, Rodolphe ULg; Demoulin, Philippe ULg et al

in Harris, N. R. P.; Guirlet, M.; Amanatidis, G. T. (Eds.) Air Pollution Report 73 EUR 19340 (2000)

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See detailLong-term evolution of the loading of CH4, N2O, CO, CCl2F2, CHClF2 and SF6 above Central Europe during the last 15 years
Zander, Rodolphe ULg; Mahieu, Emmanuel ULg; Demoulin, Philippe ULg et al

in J. van Ham (Ed.) Non-CO2 greenhouse gases: scientific understanding, control and implementation (2000)

Long-term monitoring activities of some 20 atmospheric constituents are continuing at the International Scientific Station of the Jungfraujoch, Switzerland, based on remote infra-red solar observations ... [more ▼]

Long-term monitoring activities of some 20 atmospheric constituents are continuing at the International Scientific Station of the Jungfraujoch, Switzerland, based on remote infra-red solar observations with high spectral resolution Fourier transform spectrometers. As a contribution to non-CO2 greenhouse gas investigations, we report the trends observed in the vertical column abundances measured regularly since the mid-1980s for CH4, N2O, CO, CCl2F2, CHClF2 and SF6. With the exception of CO, all species show positive rates of change in their near past atmospheric loading, those of CH4, N2O and CCl2F2 having slowed significantly during the more recent years. The derived rates of change will be compared to findings resulting from ground-level in situ investigations at latitudes similar to that of the Jungfraujoch, and be interpreted in terms of resulting global loading changes. [less ▲]

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See detailTropospheric boundary layer investigations by differential ground-based solar FTIR spectrometry
Barret, Brice; Mahieu, Emmanuel ULg; Carleer, Michel et al

in Carleer, Michel; Hilton, Moira; Lamp, Thorsten (Eds.) et al Environmental Sensing and Applications (Proceedings Volume) (1999, September 16)

In order to better understand the chemistry and the transport mechanisms in the lower troposphere, a new original technique has been developed and tested. The experiment consists in recording high ... [more ▼]

In order to better understand the chemistry and the transport mechanisms in the lower troposphere, a new original technique has been developed and tested. The experiment consists in recording high resolution infrared solar absorption spectra containing signatures of important atmospheric constituents, simultaneously from the International Scientific Station of the Jungfraujoch in Switzerland [ISSJ, 3580 m a.s.l., 46.5 degrees N, 8 degrees E, Bruker 120 HR Fourier transform spectrometer (FTS)] and from a nearby valley (Grindelwald, 1070 m a.s.l., Bruker 120 M FTS). Analysis of individual spectra allows to determine vertical column abundances: differences between measurements at ISSJ and at Grindelwald enable us to retrieve the constituents' concentrations between 1070 m and 3580 m, assuming a constant volume mixing ratio in this layer. A first measurement campaign has been organized during the months of May and June 1998. After an initial period of instrument intercomparison at ISSJ, the mobile instrument was moved down in the valley and installed for one month in Grindelwald. When operated side by side at the Jungfraujoch, measurements made by both instruments showed a very good agreement (maximum bias of 1.5%). Analysis of spectra recorded synchronously at the Jungfraujoch and at Grindelwald gave average boundary layer concentrations for a selected set of tropospheric molecules, i.e. methane, nitrous oxide, carbon monoxide and ethane. Comparison with other results and with carbon monoxide in-situ measurements made at ISSJ showed a good agreement. [less ▲]

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See detailLong-lived organic compounds (Chapter 1)
Prinn, R.; Zander, Rodolphe ULg; Cunnold, D. M. et al

in Albritton; Aucamp, Pieter J.; Mégie, Gérard (Eds.) et al Scientific Assessment of Ozone Depletion: 1998 (1999)

This assessment report is a summary of the scientific community's current understanding of the stratospheric ozone layer and its relation to humankind.

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See detailPolar stratospheric descent of NOy and CO and Arctic denitrification during winter 1992-1993
Rinsland, C. P.; Salawitch, R. J.; Gunson, M. R. et al

in Journal Of Geophysical Research. Atmospheres (1999), 104(D1), 1847-1861

Observations inside the November 1994 Antarctic stratospheric vortex and inside the April 1993 remnant Arctic stratospheric vortex by the Atmospheric Trace Molecule Spectroscopy (ATMOS) Fourier transform ... [more ▼]

Observations inside the November 1994 Antarctic stratospheric vortex and inside the April 1993 remnant Arctic stratospheric vortex by the Atmospheric Trace Molecule Spectroscopy (ATMOS) Fourier transform spectrometer are reported. In both instances, elevated volume mixing ratios (VMRs) of carbon monoxide (CO) were measured. A peak Antarctic CO VMR of 60 ppbv (where 1 ppbv = 10(-9) per unit volume) was measured at a potential temperature (Theta) of 710 K (similar to 27 km), about 1 km below the altitude of a pocket of elevated NOy (total reactive nitrogen) at a deep minimum in N2O (<5 ppbv). The Arctic observations also show a region of elevated vortex CO with a peak VMR of 90 ppbv at 630-670 K (similar to 25 km) but no corresponding enhancement in NOy, perhaps because of stronger dynamical activity in the northern hemisphere polar winter and/or interannual variability in the production of mesospheric NO. By comparing vortex and extravortex observations of NOy obtained at the same N2O VMR, Arctic vortex denitrification of 5 +/- 2 ppbv at 470 K (similar to 18 km) is inferred. We show that our conclusion of substantial Arctic winter 1992-1993 denitrification is robust by comparing our extravortex observations with previous polar measurements obtained over a wide range of winter conditions. Correlations of NOy with N2O measured at the same Theta by ATMOS in the Arctic vortex and at midlatitudes on board the ER-2 aircraft several weeks later lie along the same mixing line. The result demonstrates the consistency of the two data sets and confirms that the ER-2 sampled fragments of the denitrified Arctic vortex following its breakup, An analysis of the ATMOS Arctic measurements of total hydrogen shows no evidence for significant dehydration inside the vortex. [less ▲]

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See detailVertical column abundances of COF2 above the Jungfraujoch Station: update and consolidation of the database with measurements in the nu4 band region.
Mélen, Francine; Mahieu, Emmanuel ULg; Demoulin, Philippe ULg et al

in Atmospheric Spectroscopy Applications 1999 - Proceedings (1999)

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See detailColumn Abundance measurements of formaldehyde above the Jungfraujoch.
Demoulin, Philippe ULg; Zander, Rodolphe ULg; Mélen, F. et al

in Atmospheric Spectroscopy Applications 1999 - Proceedings (1999)

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See detailQuantitative evaluation of the post-Mount Pinatubo NO2 reduction and recovery, based on 10 years of Fourier transform infrared and UV-visible spectroscopic measurements at Jungfraujoch
De Mazière, Martine; Van Roozendael, Michel; Hermans, Christian et al

in Journal of Geophysical Research (1998), 103(D9), 10849-10858

The colocation of two technically different instruments for ground-based remote sensing of NO2 total column amounts at the primary Network for the Detection of Stratospheric Change Alpine station of the ... [more ▼]

The colocation of two technically different instruments for ground-based remote sensing of NO2 total column amounts at the primary Network for the Detection of Stratospheric Change Alpine station of the Jungfraujoch (46.5°N, 8.0°E) has been exploited for mutual validation of the long-term NO2 time series from both instruments and for a quantitative evaluation of the impact of the Mount Pinatubo eruption on the NO2 abundance above this northern mid-latitude observatory. The two techniques are high-resolution Fourier transform infrared solar absorption spectrometry and zenith-sky differential optical absorption spectroscopy in the UV visible. The diurnal variation of NO2 has been simulated by a simple photochemical model that allows a comparison between the data from the two techniques. This model is shown to reproduce the observed morning to evening ratios to 2.3%, on average, which is fully adequate for the needs of this study. From the 1985–1996 combined time series of NO2 morning and evening abundances, it has been concluded that the enhanced aerosol load injected into the stratosphere by Mount Pinatubo caused a maximum NO2 reduction above the Jungfraujoch by 45% in early January 1992 that died out quasi-exponentially to zero by the beginning of 1995. [less ▲]

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See detailRecent Characteristic Budgets of Inorganic Chlorine and Fluorine above the Jungfraujoch Station
Mahieu, Emmanuel ULg; Zander, Rodolphe ULg; Mélen, Francine et al

in Harris, N. R. P.; Kilbane-Dawe, I.; Amanatidis, G.T. (Eds.) Proceedings of the 4th European Symposium on Polar Stratospheric Ozone 1997 (1998)

Within the frame of NDSC (Network for the Detection of Stratospheric Change)-related monitoring activities conducted at the International Scientific Station of the Jungfraujoch (Swiss Alps, 46.5°N, 8.0°E ... [more ▼]

Within the frame of NDSC (Network for the Detection of Stratospheric Change)-related monitoring activities conducted at the International Scientific Station of the Jungfraujoch (Swiss Alps, 46.5°N, 8.0°E, 3580 m a.s.l.), long-term investigations of the inorganic chlorine and fluorine budgets have been pursued during the last years. They are based on the analysis of high-resolution infrared solar spectra, recorded with grating and Fourier transform state-of-the-art spectrometers. Nonlinear least squares fittings of synthetic spectra to the observations are performed over selected intervals, encompassing characteristic absorptions of HCl, ClONO2, HF and COF2; this allows the retrieval of their total vertical column abundances above the Jungfraujoch and the evaluation of their budgets. [less ▲]

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See detailGround-based FTIR Measurements from a Series of European sites during the Winter of 1995/96 and a Comparison with a 3D Chemical Transport Model: Evidence of Chlorine Activation and Ozone depletion
Paton Walsh, C.; Bell, W.; Blumenstock, T. et al

in Harris, N. R. P.; Kilbane-Dawe, I.; Amanatidis, G.T. (Eds.) Polar stratospheric ozone 1997 (1998)

Fourier transform infra-red (FTIR) measurements of stratospheric trace species have been made at a network of five ground-based sites from 79°N to 47°N during the Northern hemisphere winter of 1995/1996 ... [more ▼]

Fourier transform infra-red (FTIR) measurements of stratospheric trace species have been made at a network of five ground-based sites from 79°N to 47°N during the Northern hemisphere winter of 1995/1996. This winter was extremely cold with temperatures below the threshold for type 1 polar stratospheric cloud (PSC) formation from mid December 1995 until early March 1996 when there was a rapid warming of the stratosphere. Over 25 days experienced temperatures low enough for ice cloud (PSC type 2) formation. Vertical columns values for HCl, ClONO2, HF and HNO3 have been derived from FTIR measurements at the following sites: Ny Alesund, Spitzbergen (79°N, 12°E); Kiruna, Sweden (67°N, 21°E); Harestua, Norway (60°N, 11°E); London, England (51°N, 0°E) and the Jungfraujoch, Switzerland (48°N, 8°E), with measurements of other stratospheric trace gases, including O3 and ClO available from some of the sites. All of these sites are equipped with high resolution Bruker 120HR or 120M spectrometers, recording atmospheric spectra in the mid infrared using the Sun as a source. These measurements have been used to provide both evidence of substantial activation within large areas of the polar vortex and a subsequent O3 depletion. The measurements suggest a well mixed central vortex area surrounded by a vortex edge that may be highly variable in composition. The measurements also provide evidence of substantial mixing of activated air from the edge of the polar vortex into middle latitudes. Comparison with the SLIMCAT 3D chemical transport model highlights the underestimation of ClONO2 concentrations in the model, with subsequent implications for underestimating O3 loss. [less ▲]

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See detailTowards improved evaluations of total ozone at the Jungfraujoch, using vertical profile estimations based on auxiliary data
De Mazière, Martine; Hennen, Olivier; Van Roozendael, Michel et al

in Proceedings of "The XXVIII Quadrennial Ozone Symposium", L’Aquila, Italy, September 12-21, 1996 (1998)

The currently available database of total ozone amounts observed at the Jungfraujoch site in the Swiss Alps starts in 1984, based on high-resolution infrared solar absorption spectroscopic measurements ... [more ▼]

The currently available database of total ozone amounts observed at the Jungfraujoch site in the Swiss Alps starts in 1984, based on high-resolution infrared solar absorption spectroscopic measurements, and has been complemented by daily SAOZ data since mid-1990. The latter instrument (Système d'Analyse par Observations Zénithales) measures the ozone column by application of the DOAS (Differential Optical Absorption Spectroscopy) method to zenith-sky scattered-light spectra in the ultraviolet-visible range, taken at twilight. The actual intercomparison for the overlapping period reveals a negative systematic offset of the FTIR with respect to the SAOZ data of 3.8 % on average, but showing a seasonal variation in the difference. Part of the observed difference probably originates in the model atmospheres that influence the retrieved column differently for each technique. This work shows the development of a climatological ozone vertical distribution model that is more representative of the real atmosphere, exploiting daily meteorological data that are commonly available at the Jungfraujoch site. It argues that the use of this climatological model may improve the accuracy of the retrieved total columns, and hence the agreement between the SAOZ and FTIR datasets; some possible improvements to the model are suggested. Application of this concept to a re-analysis of past observations, making use of existing meteorological long-term records, will enhance the validity of the ozone database at the Jungfraujoch. [less ▲]

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See detailThe current budget of NOy above the Jungfraujoch as derived from IR solar observations
Demoulin, Philippe ULg; Mahieu, Emmanuel ULg; Zander, Rodolphe ULg et al

in Harris, N. R. P.; Kilbane-Dawe, I.; Amanatidis, G. T. (Eds.) Polar stratospheric ozone 1997 (1998)

This paper reports on an investigations of a series of compounds of the NOy family, based on high resolution infrared solar observations made at the ISSJ (International Scientific Station of the ... [more ▼]

This paper reports on an investigations of a series of compounds of the NOy family, based on high resolution infrared solar observations made at the ISSJ (International Scientific Station of the Jungfraujoch), Switzerland (46.55ºN, 7.99ºE, 3580 m a.s.l.). These observations are part of a long-term monitoring effort undertaken by the Liège group since the mid-1970s, and integrated more recently as a contribution to the Network for the Detection of Stratospheric Change (NDSC). Currently, vertical column abundances of over 20 molecules are retrieved from solar spectra recorded under clear sky conditions as regularly as possible, using two high resolution Fourier transform infrared (2 to 15 microns) spectrometers. [less ▲]

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See detailAn overview of NDSC-related activities at the Jungfraujoch through high-resolution infrared solar observations
Zander, Rodolphe ULg; Demoulin, Philippe ULg; Mahieu, Emmanuel ULg et al

in Bojkov, R.; Visconti, G. (Eds.) Proceedings of "The XXVIII Quadrennial Ozone Symposium" (1998)

Since the mid-1970s, infrared remote sensing at the Jungfraujoch, Switzerland, has been performed in response to the need to measure the concentrations and assess the seasonal and long-term changes of an ... [more ▼]

Since the mid-1970s, infrared remote sensing at the Jungfraujoch, Switzerland, has been performed in response to the need to measure the concentrations and assess the seasonal and long-term changes of an increasing number of atmospheric constituents. Currently, the vertical column abundances of over 20 telluric gases are being monitored, based on the analysis of solar spectra recorded regularly between 2 and 14 microns, using two high-resolution Fourier transform spectrometers. In this paper, emphasis is placed on those activities more specifically performed within the framework of the NDSC (Network for the Detection of Stratospheric Change) whose objectives are briefly described in the introduction. [less ▲]

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See detailVertical column abundances of COF2 above the Jungfraujoch Station, derived from ground-based infrared solar observations
Mélen, F.; Mahieu, Emmanuel ULg; Zander, Rodolphe ULg et al

in Journal of Atmospheric Chemistry (1998), 29(2), 119-134

Total vertical column abundances of carbonyl fluoride (COF2) have been derived from observations made at the International Scientific Station of the Jungfraujoch (ISSJ; altitude 3.58 km, latitude 46.5 ... [more ▼]

Total vertical column abundances of carbonyl fluoride (COF2) have been derived from observations made at the International Scientific Station of the Jungfraujoch (ISSJ; altitude 3.58 km, latitude 46.5 degrees N, longitude 8.0 degrees E), Switzerland. A systematic analysis of two microwindows containing lines of the vi band was performed, based on a large set of high resolution infrared solar absorption spectra recorded with Fourier transform spectrometers, from 1985 to 1995. Examination of the whole available database indicates a significant increase of the burden of COF2 during the 1988-1995 period. The average exponential rate and the average linear rate referenced to 1992, calculated from daily mean measurements, are both equal to (4.0 +/- 0.5)% yr(-1) (one sigma error). The results are also evaluated and discussed within the context of seasonal variability and correlation between carbonyl fluoride and hydrogen fluoride (HF) columns above the ISSJ. [less ▲]

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See detailATMOS/ATLAS 3 infrared profile measurements of clouds in the tropical and subtropical upper troposphere
Rinsland, C. P.; Gunson, M. R.; Wang, P.-H. et al

in Journal of Quantitative Spectroscopy & Radiative Transfer (1998), 60(5), 903-919

Vertical profiles of infrared cirrus extinction have been derived from tropical and subtropical upper tropospheric solar occultation spectra. The measurements were recorded by the Atmospheric Trace ... [more ▼]

Vertical profiles of infrared cirrus extinction have been derived from tropical and subtropical upper tropospheric solar occultation spectra. The measurements were recorded by the Atmospheric Trace Molecule Spectroscopy (ATMOS) Fourier transform spectrometer during the Atmospheric Laboratory for Applications and Sciences (ATLAS) 3 shuttle flight in November 1994. The presence of large numbers of small ice crystals is inferred from the appearance of broad extinction features in the 8-12 mu m region. These features were observed near the tropopause and at lower altitudes. Vertical profiles of the ice extinction (km(-1)) in microwindows at 831, 957, and 1204 cm(-1) have been retrieved from the spectra and analyzed with a model for randomly oriented spheroidal ice crystals. An area-equivalent spherical radius of 6 mu m is estimated from the smallest ice crystals observed in the 8-12 mu m region. Direct penetration of clouds into the lower stratosphere is inferred from observations of cloud extinction extending from the upper troposphere to 50 mbar (20 km altitude). Cloud extinction between 3 and 5 mu m shows very little wavelength dependence, at least for the cases observed by the ATMOS instrument in the tropics and subtropics during ATLAS 3. Published by Elsevier Science Ltd. [less ▲]

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See detailATMOS/ATLAS 3 infrared profile measurements of trace gases in the November 1994 tropical and subtropical upper troposphere
Rinsland, C. P.; Gunson, M. R.; Wang, P.-H. et al

in Journal of Quantitative Spectroscopy & Radiative Transfer (1998), 60(5), 891-901

Vertical mixing ratio profiles of four relatively long-lives gases, HCN, C2H2, CO, and C2H6, have been retrieved from 0.01 cm(-1) resolution infrared solar occultation spectra recorded between latitudes ... [more ▼]

Vertical mixing ratio profiles of four relatively long-lives gases, HCN, C2H2, CO, and C2H6, have been retrieved from 0.01 cm(-1) resolution infrared solar occultation spectra recorded between latitudes of 5.3 degrees N and 31.4 degrees N. The observations were obtained by the Atmospheric Trace Molecule Spectroscopy (ATMOS) Fourier transform spectrometer during the Atmospheric Laboratory for Applications and Science (ATLAS) 3 shuttle flight, 3-12 November 1994. Elevated mixing ratios below the tropopause were measured for these gases during several of the occultations. The positive correlations obtained between the simultaneously measured mixing ratios suggest that the enhancements are likely the result of surface emissions, most likely biomass burning and/or urban industrial activities, followed by common injection via deep convective transport of the gases to the upper troposphere. The elevated levels of HCN may account for at least part of the "missing NOy" in the upper troposphere. Comparisons of the observations with values measured during a recent aircraft campaign are presented. Published by Elsevier Science Ltd. [less ▲]

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