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The article focuses on a study on water vapour spectroscopy and its impact on the ratio of heavy water (HDO) and water (H2O) in Scanning Imaging Absorption spectrometer for Atmospheric Cartography (SCIAMACHY). In the study,the impact of updated water spectroscopy is tested on total column retrievals of high-resolution Fourier-Transform Spectrometers (FTS). It shows negative shift in the HDO/H2O ratio for both the SCHIAMACHY and FTS measurements.

Ground-based high spectral resolution Fouriertransform infrared (FTIR) solar absorption spectroscopy is a powerful remote sensing technique to obtain information on the total column abundances and on the vertical distribution of various constituents in the atmosphere. This work presents results from two FTIR measurement campaigns in 2002 and 2004, held at Ile de La Réunion (21° S, 55° E). These campaigns represent the first FTIR observations carried out at a southern (sub)tropical site. They serve the initiation of regular, long-term FTIR monitoring at this site in the near future. To demonstrate the capabilities of the FTIR measurements at this location for tropospheric and stratospheric monitoring, a detailed report is given on the retrieval strategy, information content and corresponding full error budget evaluation for ozone (O3), methane (CH4), nitrous oxide (N2O), carbon monoxide (CO), ethane (C2H6), hydrogen chloride (HCl), hydrogen fluoride (HF) and nitric acid (HNO3) total and partial column retrievals. Moreover, we have made a thorough comparison of the capabilities at sea level altitude (St.-Denis) and at 2200m a.s.l. (Maïdo). It is proved that the performances of the technique are such that the atmospheric variability can be observed, at both locations and in distinct altitude layers. Comparisons with literature and with correlative data from ozone sonde and satellite (i.e., ACE-FTS, HALOE and MOPITT) measurements are given to confirm the results. Despite the short time series available at present, we have been able to detect the seasonal variation of CO in the biomass burning season, as well as the impact of particular biomass burning events in Africa and Madagascar on the atmospheric composition above Ile de La Réunion. We also show that differential measurements between St.-Denis and Maïdo provide useful information about the concentrations in the boundary layer. [ABSTRACT FROM AUTHOR]

Abstract: Absorption cross sections of SO2 have been obtained in the 24000–29000cm−1 spectral range (345–420nm) with a Fourier transform spectrometer at a resolution of 2cm−1. Pure SO2 samples were used and measurements were performed at room temperature (298K) as well as at 318, 338 and 358K. This is the first time that temperature effects in this spectral region are reported and investigated. This paper is the first of a series that will report on measurements of the absorption cross section of SO2 in the UV/visible region at a higher than previously reported resolution and that will investigate temperature effects in support of tropospheric, stratospheric and astrophysical or planetary applications. [Copyright &y& Elsevier]

The measurements of the NO2 absorption cross sections by several authors have been considered in order to derive its temperature and pressure dependences in the 13 200–42 000 cm−1 spectral range. The temperature dependence is assumed to be linear in the temperature range investigated (217.0–298.5 K), whereas the influence of the total pressure is expressed as a temperature-dependent broadening coefficient. From measurements performed with mixtures of NO2 in air and in N2, values of γair0 (296 K) and γN20 (296 K) were found to be, respectively, 0.081±0.002 and 0.069±0.003 cm−1 atm−1. The temperature coefficient n obtained in the present work is 0.8±0.1. The parameterization of the cross sections developed in this work can reproduce measured cross sections within 4%. [Copyright &y& Elsevier]

Abstract: This paper describes the status of the 2008 edition of the HITRAN molecular spectroscopic database. The new edition is the first official public release since the 2004 edition, although a number of crucial updates had been made available online since 2004. The HITRAN compilation consists of several components that serve as input for radiative-transfer calculation codes: individual line parameters for the microwave through visible spectra of molecules in the gas phase; absorption cross-sections for molecules having dense spectral features, i.e. spectra in which the individual lines are not resolved; individual line parameters and absorption cross-sections for bands in the ultraviolet; refractive indices of aerosols, tables and files of general properties associated with the database; and database management software. The line-by-line portion of the database contains spectroscopic parameters for 42 molecules including many of their isotopologues. [Copyright &y& Elsevier]

Abstract: Assignment of an HDO line list extracted from a recently measured H2O/HDO/D2O Fourier transform absorption spectrum recorded in the 11600–23000cm−1 region by Bach et al. (M. Bach, S. Fally, P.-F. Coheur, M. Carleer, A. Jenouvrier, A.C. Vandaele, J. Mol. Spectrosc. 232 (2005) 341–350.) is presented. More than 94% of the 3256 lines are given quantum number assignments and ascribed to line absorption by HDO; most of the remaining lines are actually due to D2O. High accuracy variational predictions of line positions and intensities are used for the spectral assignment process. Assignments to the ν 1 +5ν 3, 2ν 2 +5ν 3, ν 1 + ν 2 +3ν 3 and ν 1 +6ν 3 bands are presented for the first time. Comparisons are made with published ICLAS spectra covering the same spectral region and suggestions made for its recalibration. The results are used to illustrate the dynamical behaviour of highly excited vibrational states of HDO and to discuss previous vibrational assignments to high lying rotation–vibration states of this system. [Copyright &y& Elsevier]