Four spectra of methane in natural isotopic abundance in the 4100-4300 cm(-1) region were recorded by using a Fourier transform spectrometer in Reims, France at long paths (202 m, 602 m, 1604 m and 1804 m) and different pressures. Additional spectra of (CH4)-C-12 covering the same region were obtained at 100-123 K for different pressures, 93 m path length at Synchrotron SOLEIL in Paris for different pressures and were used to measure low-J lines. Spectra of (CH4)-C-12 and (CH4)-C-13 obtained at 80 K at JPL in Pasadena were used for additional frequency calibrations. Line positions and intensities were retrieved by non-linear least-squares curve-fitting procedures and analyzed using effective Hamiltonian and effective dipole transition moment models. A new measured line list contains positions and intensities for 12,378 features. Quantum assignments were made for more than 11,520 new transitions, which represent similar to 99% of the integrated line intensity observed in this region. Some of 4556 hot band transitions for (Dyad - Tetradecad) system were assigned. The resulting list of lines is significantly more accurate than previous empirical compilations. All assigned 6963 line positions were fitted to RMS standard deviations of 0.0015 cm(-1). The sum of the observed intensities between 4100 and 4300 cm(-1) falls within 5% of the predicted value from ab initio variational calculations reported in the TheoReTS database (http: //theorets.univ-reims.fr ; http://theorets.tsu.u). (C) 2021 Elsevier Ltd. All rights reserved.

Four spectra of normal samples of CH4 in the 4300-4600 cm(-1) region were recorded by using a Fourier transform spectrometer in Reims, France at long paths (202m, 602m, 1604m, and 1804m) and different pressures. Additional spectra of (CH4)-C-12 covering the same region were obtained at 80-123 K, and 93 m path length at SOLEIL Synchrotron in Paris for different pressures and were used to measure low-J lines. Line positions and intensities were retrieved by non-linear least-squares curve-fitting procedures and an- alyzed using effective Hamiltonian and effective dipole transition moment models. A new measured line list contains positions and intensities for 14,151 absorption features. Quantum assignments were made for more than 10,304 transitions of (CH4)-C-12, which represent -99% of the integrated line intensity observed in this region. Some 1699 hot band transitions for (Dyad - Tetradecad) system were assigned. The resulting list of lines is significantly more accurate than previous empirical compilations. Positions of 8605 cold band transitions for (GS - Octad) system were fitted with an RMS standard deviation of 0.0014 cm(-1). The sum of observed intensities between 4300 and 4600 cm(-1) fell within 8% of the predicted value from ab initio variational calculations reported in the TheoReTS database (http://theorets.univ-reims.fr;http://thearets.tsu.ru). (C) 2020 Elsevier Ltd. All rights reserved.

This study is a continuation of experimental efforts on the analysis of the near-infrared absorption spectrum of water vapor. Our previous studies were focused on water vapor in natural isotopic abundance. Now we are interested in the (H2O)-O-18 water isotopologue. New spectra of water samples enriched by O-18 were recorded between 6400 and 9400 cm(-1) in Reims with the Connes-type Fourier Transform Spectrometer, built in our laboratory. The spectra were recorded at room temperature with a (H2O)-O-18 abundance enrichment of about 95% and a non apodized resolution of 0.010 cm(-1). Pressure varied from 2 to 13 torr and the absorption path length was from 67 cm to 1001 m. This article presents the results of the analysis of the first part of the whole recorded spectral range below 8000 cm(-1). About 8100 absorption lines were found in the recorded spectra with an absorption path length from 8 to 88 m between 6525 and 8011 cm(-1). Overall, 7993 lines were assigned to 8647 transitions of six water isotopologues ((H2O)-O-16, (H2O)-O-17, (H2O)-O-18, (HDO)-O-16, (HDO)-O-17, and (HDO)-O-18). Ninety-eight lines with intensity values between 6 x 10(-27) and 1.45 x 10(-25) cm/molecule were left unassigned. More than 870 (H2O)-O-18, (H2O)-O-17 and (HDO)-O-18 lines were observed for the first time. The observed line positions allow to obtain about 90 new or corrected rotation-vibration energy levels of (H2O)-O-18 and (H2O)-O-17. Comparison of line positions and intensities with literature data are presented and discussed. Some examples of disagreements between the measurements and data from the literature are presented in the last part of this article. (C) 2019 Elsevier Ltd. All rights reserved.

For decades, the remote sensing measurements have been made in planetary atmospheres in the Solar System and beyond. As the performance of the space instruments improves, the atmospheric science community is more and more in need of accurate spectroscopic data. The current databases offer some parameters for non-Earth atmospheres but are far from complete for all situations. For example, measured H2O line parameters in CO2-rich atmospheres such as Mars and Venus are missing while they are of prime importance to learn about the evolution of the atmospheres. New Fourier Transform Spectrometer spectra were recorded respectively around 2.7 and 6 m, using a Connes' type FT spectrometer built in Reims. The spectra were analysed using a multispectrum fitting procedure to obtain the line-shape parameters of H2O broadened by CO2. Modified Complex Robert-Bonamy calculations of the half-width, line shift, and their temperature dependence were made in the spectral region from 1300 to 5000 cm(-1). The measurements and calculations are presented and compared with data available in the literature. (C) 2019 Elsevier Ltd. All rights reserved.

The Fourier transform spectrum of CF4 in the 1600-1800 cm(-1) was recorded in Reims by using a White-type multi-pass cell to provide a path length of 8.262 m. In the present work, all spectrum analyses and fits were realized using the MIRS software based on tetrahedral tensorial formalism. By combining non-empirical contact transformation Hamiltonians for line positions and ab initio ro-vibrational normal-mode predictions for line intensities, we are able to achieve a simultaneous fit of effective Hamiltonian and dipole moment parameters of several cold and hot bands of CF4. Hamiltonian operator was expanded up to the sixth order for the ground state and for the {nu(2) + 2 nu(4), nu(2) + nu(3), 4 nu(2), nu(1) + 2 nu(2), 2 nu(1)} pentad. 1831 line positions were fitted to RMS of 1.5X10(-3) cm(-1). The standard deviation for line intensities for the cold bands {nu(2) + 2 nu(4), nu(2) + nu(3), 4 nu(2), nu(1) + 2 nu(2), 2 nu(1)} is of 1.1% and of 8% and 5% for the hot band transitions {2 nu(2) + 2 nu(4) - nu(2), 2 nu(2) + nu(3) - nu(2)} and {nu(2) + 3 nu(4) - nu(4), nu(2) + nu(3) + nu(4) - nu(4)}, respectively. (C) 2019 Elsevier Ltd. All rights reserved.

Eight spectra of normal samples of CH4 in the 3760-4100 cm(-1) region were recorded by using a Fourier transform spectrometer in Reims, France at long paths (202 m, 602 m, 1604 m and 1804 m) and different pressures. Additional spectra of (CH4)-C-12 covering the same region were obtained at 100 K and very low sample pressures, which was used for low-J line position identification. Line positions and intensities were retrieved by least squares curve-fitting procedures and analyzed using the effective Hamiltonian and the effective dipole. A new measured line list contains positions and intensities for 9000 features. Quantum assignments were made for more than 3500 new transitions, which represent similar to 95% of the integrated line intensity observed in this region. The resulting list of lines is much more accurate than the list of lines HITRAN 2016. All assigned 5703 line positions were fitted to RMS standard deviations of 0.0018 cm(-1). The sum of observed intensities between 3760 and 4100 cm(-1) fell within 2% of the predicted value from ab initio variational calculations reported in the TheoReTS database (http://theorets.univ-reims.fr; http://theorets.tsu.ru). (C) 2018 Elsevier Ltd. All rights reserved.

A new study of (CH4)-C-12 line positions and intensities was performed for the Tetradecad regions 5550,000-5695.250, 5718.8-5724.250 and 5792.36-5814.290 cm(-1) using long path (202 m, 602 m, 1604 m and 1804 m) spectra of normal samples of CH4 at different pressures recorded with a Fourier transform spectrometer in Reims, France. Line positions and intensities were retrieved by least squares curve-fitting procedures and analyzed using the effective Hamiltonian and the effective dipole moment expressed in terms of irreducible tensor operators adapted to spherical top molecules. An 80 K spectrum recorded in Jet Propulsion Laboratory (JPL), Pasadena, of enriched (CH4)-C-12 was used for low-J line positions. Another 80 K spectrum of enriched (CH4)-C-13 from JPL was used to discern the isotopic lines. A new measured linelist contains positions and intensities for 5819 features. Quantum assignments were made for more than 3400 transitions, which represent similar to 95% of the integrated line intensity observed in this region. All assigned 3445 line positions were fitted with RMS standard deviations of 0.0024 cm(-1). The sum of observed intensities between 5550 and 5695 cm(-1) fell within 2% of the predicted value from ab initio variational calculations reported in the TheoReTS database (http://theorets.univ-reims.fr; http://theorets.tsu.ru). (C) 2018 Elsevier Ltd. All rights reserved.

CF4, or tetrafluoromethane, is a chemically inert and strongly absorbing greenhouse gas, mainly of anthropogenic origin. In order to monitor and reduce its atmospheric emissions and concentration, it is thus necessary to obtain an accurate model of its infrared absorption. Such models allow opacity calculations for radiative transfer atmospheric models. In the present work, we perform a global analysis (divided into two distinct fitting schemes) of 17 rovibrational bands of CF4. This gives a reliable model of many of its lower rovibrational levels and allows the calculation of the infrared absorption in the strongly absorbing upsilon(3) region (1283 cm(-1) / 7.8 mu m), including the main hot band, namely upsilon(3) + upsilon(2) - upsilon(2) as well as upsilon(3) + upsilon(1) - upsilon(1); we could also extrapolate the upsilon(3) + upsilon(4) - upsilon(4) absorption. This represents almost 92% of the absorption at room temperature in this spectral region. A new accurate value of the C-F bond length is evaluated to r(e) = 1.314860(21)angstrom. The present results have been used to update the HITRAN, GEISA and TFMeCaSDa (VAMDC) databases. (C) 2017 Elsevier Ltd. All rights reserved.

An update of the former version of the database and software for the calculation of CO2–air absorption coefficients taking line-mixing into account [Lamouroux et al. J Quant Spectrosc Radiat Transf 2010;111:2321] is described. In this new edition, the data sets were constructed using parameters from the 2012 version of the HITRAN database and recent measurements of line-shape parameters. Among other improvements, speed-dependent profiles can now be used if line-mixing is treated within the first order approximation. This new package is tested using laboratory spectra measured in the 2.1μm and 4.3μm spectral regions for various pressures, temperatures and CO2 concentration conditions. Despite improvements at 4.3μm at room temperature, the conclusions on the quality of this update are more ambiguous at low temperature and in the 2.1μm region. Further tests using laboratory and atmospheric spectra are thus required for the evaluation of the performances of this updated package.

A new study of 12CH4 line positions and intensities was performed for the lower portion of the Tetradecad region between 4800 and 5300 cm−1 using long path (1603 m) spectra of normal sample CH4 at three pressures recorded with the Fourier transform spectrometer in Reims, France. Line positions and intensities were retrieved by least square curve-fitting procedures and analyzed using the effective Hamiltonian and the effective Dipole moment expressed in terms of irreducible tensor operators adapted to spherical top molecules. An existing spectrum of enriched 13CH4 was used to discern the isotopic lines. A new measured linelist produced positions and intensities for 5851 features (a factor of two more than prior work). Assignments were made for 46% of these; 2725 experimental line positions and 1764 selected line intensities were fitted with RMS standard deviations of 0.004 cm−1 and 7.3%, respectively. The RMS of prior intensity fits of the lower Tetradecad was previously a factor of two worse. The sum of observed intensities between 4800 and 5300 cm−1 fell within 5% of the predicted value from variational calculations.

This work continues the systematic investigation of high resolution infrared spectra of 18O enriched ozone isotopologues in the 4500–6300cm−1 spectral range. So far, the 16O18O16O and 18O16O18O spectra have been recorded and analysed using Fourier Transform Spectrometer (FTS) below 5000cm−1 and using high sensitivity Cavity Ring-Down Spectroscopy above 6000cm−1. In order to fill the gap between 5000 and 6000cm−1, new infrared spectra were recorded with the Reims FTS. The analyses of the 2ν1+ν2+3ν3 band of 16O18O16O and of the 5ν3, ν1+2ν2+3ν3 and ν1+5ν3 bands of 18O16O18O are reported. New ν1+2ν2+3ν3 and ν1+5ν3 bands of 18O3 were also observed and analysed. Observed line positions were fitted using effective Hamiltonian models accounting for the dark state perturbations. The derived band centres and rotational constants are in a good agreement with new theoretical calculations from the molecular potential function.

The spectra of natural water vapor were recorded in the spectral range 6450–9400cm−1 with a step-by-step Fourier transform spectrometer at room temperature with absorption path lengths up to 1200m. Positions, intensities and self-broadening coefficients of about 11,000 lines were determined. This paper focuses on the intensity parameters: the lines of four isotopologues H216O, H218O, H217O and HD16O were observed and assigned; it presents a new experimental dataset in the 6450–9400cm−1 spectral range. Obtained results were compared to the literature data. Fifty-nine new and corrected energy levels of H216O and H217O were determined from the vibration–rotation analysis of the observed lines. A brief discussion is added for self-broadening coefficients at the end of this paper.

Emissions of CH4 and N2O related to private pig farming under a tropical climate in Uvéa Island were studied in this paper. Physicochemical soil parameters such as nitrate, nitrite, ammonium, Kjeldahl nitrogen, total organic carbon, pH and moisture were measured. Gaseous soil emissions as well as physicochemical parameters were compared in two private pig farming strategies encountered on this island on two different soils (calcareous and ferralitic) in order to determine the best pig farming management: in small concrete pens or in large land pens. Ammonium levels were higher in control areas while nitrate and nitrite levels were higher in soils with pig slurry inputs, indicating that nitrification was the predominant process related to N2O emissions. Nitrate contents in soils near concrete pens were important (≥ 55 μg N/g) and can thus be a threat for the groundwater. For both pig farming strategies, N2O and CH4 fluxes can reach high levels up to 1 mg N/m(2)/h and 1 mg C/m(2)/h, respectively. CH4 emissions near concrete pens were very high (≥ 10.4 mg C/m(2)/h). Former land pens converted into agricultural land recover low N2O emission rates (≤ 0.03 mg N/m(2)/h), and methane uptake dominates. N2O emissions were related to nitrate content whereas CH4 emissions were found to be moisture dependent. As a result relating to the physicochemical parameters as well as to the gaseous emissions, we demonstrate that pig farming in large land pens is the best strategy for sustainable family pig breeding in Uvéa Islands and therefore in similar small tropical islands.

This paper describes a Quantum Cascade Laser Absorption Spectrometer, called "QCLAS" that was developed to monitor in situ greenhouse gases like N2O and CH4, at high temporal resolution and with a high accuracy. The design of the laser sensor is reported as well as its performances in terms of precision error and field deployment capabilities. Finally, to demonstrate the efficiency and the robustness of QCLAS and its suitability for gas emission monitoring and for the determination of fluxes, we report the results from a field campaign, that took place in the Wallis and Futuna Islands in 2011, to investigate the impact of environmental intensive pig farming.

The compilation of methane molecular line parameters was updated to include new global analyses and measurements for 12CH4, 13CH4 and 12CH3D. Over 70% of the methane parameters in HITRAN2008 were replaced; existing parameters retained were the microwave lines and the Dyad of 13CH4 near 7μm and ν6 of 13CH3D near 8.7μm, 12CH3D (7–4076cm−1), hot bands of 12CH4 (1887–3370cm−1) and normal sample CH4 (4800–5550cm−1 and 8000–9200cm−1). With a minimum intensity at 296K in units of cm−1/(moleculecm−2) set to 10–37 for the far-IR and 10–29 for the mid- and near-IR, the methane database increased from 290,091 lines in HITRAN2008 to 468,013 lines, and three-fourths of these involved the main isotopologue. For 12CH4 and 13CH4, bands from the ground state were revised up to 4800cm−1. For the first time, 13CH4 and 12CH3D line parameters near 2.3μm were included. Above 5550cm−1, the new compilation was based on empirical measurements. Prior laboratory results were replaced with extensive new measurements using FTIR (5550–5852cm−1), differential absorption spectroscopy (DAS) and Cavity Ring Down Spectroscopy (CRDS) (5852–7912cm−1). Ground state J values for nearly half of the measured lines in this range were obtained, either by confirming quantum assignments of analyses or by using spectra at 80 and 296K. Finally, over 11,000 measured positions, intensities and empirical lower state energies (obtained using cold CH4) were also added for the first time between 10,923 and 11,502cm−1. Available pressure broadening measurements from HITRAN2008 were transferred into the new compilation, but 99% of the lines were given crudely-estimated coefficients. New measured intensities and broadening coefficients were included for far-IR transitions, and high accuracy line positions were inserted for the stronger P, Q and R branch transitions of ν3 at 3.3μm and 2ν3 at 1.66µm.

This paper reports new assignments of rovibrational transitions of 12CH4 bands in the range 4600–4887 cm−1 which is usually referred to as a part of the 2μm methane transparency window. Several experimental data sources for methane line positions and intensities were combined for this analysis. Three long path Fourier transform spectra newly recorded in Reims with 1603m absorption path length and pressures of 1, 7 and 34hPa for samples of natural abundance CH4 provided new measurements of 12CH4 lines. Older spectra for 13CH4 (90% purity) from JPL with 73m absorption path length were used to identify the corresponding lines. Most of the lines in this region belong to the Octad system of 12CH4. The new spectra allowed us to assign 1014 new line positions and to measure 1095 line intensities in the cold bands of the Octad. These new line positions and intensities were added to the global fit of Hamiltonian and dipole moment parameters of the Ground State, Dyad, Pentad and Octad systems. This leads to a noticeable improvement of the theoretical description in this methane transparency window and a better global prediction of the methane spectrum.

The infrared spectrum of O-16(3) has been revisited in the ranges 3300-3600 cm(-1) and 52005600 cm(-1), recorded by the Fourier Transform Spectrometer of Reims, with an improved signal/noise ratio. In the lower spectral range the weak 2v(1) + 2v(2) band is observed and assigned for the first time. This allowed for completing the triad of strongly interacting (220), (121), and (022) states. The resonance interaction parameters for this triad were derived from the molecular potential energy surface using high-order Contact Transformation method. This involves Darling-Dennison resonances between (220) and (022) vibration A-states, and Coriolis resonances between (121) B-state and A-states. Altogether 18 coupling parameters were fixed to these theoretically predicted values that allowed avoiding problems of ambiguities while fitting strongly correlated parameters. The remaining small perturbations of a few K-a=5 transitions of the v(1) + 2v(2) + v(3) band were explained by accidental Coriolis resonance of (121) with the (050) dark state. This mixed half theoretical/half empirical model (with 39 fitted and 77 theoretically constrained parameters) developed in this work for the first time allows an excellent description of 1897 line positions with the rms deviation similar to 0.001 cm(-1) closed to the experimental precision. The intensities of two new hot bands v(2) + 4v(3) - v(3) and v(1) + v(2) + 3v(3) - v(1) that fall in this range were also observed and modelled, thanks to a better signal to noise ratio.In addition, the 5200-5600 cm(-1) region has also been revisited, showing for the first time the (321) state which was considered as "dark" one in the previous analysis. Effective Hamiltonian parameters were derived for strongly coupled (213)/(114)/(321) upper states including (080) as a dark one.The transition moment parameters of all newly observed and assigned bands were derived resulting to average rms deviation for intensities of similar to 8% and 13% for the cold and the hot bands, respectively, in the lower range and of similar to 15% for the bands in the upper range that is close to experimental accuracy for weak transitions. (C) 2012 Elsevier Ltd. All rights reserved.

The spectra of water vapor enriched by 18O were recorded in the 1000–2300cm−1 spectral range, which corresponds to the spectral region studied by IASI instrument (Infrared Atmospheric Sounding Spectrometer) instrument. The spectra were recorded by a step by step Fourier Transform Spectrometer (FTS) at room temperature with absorption path lengths up to 36m. Positions, intensities and self broadening coefficients of about 1800 lines of H218O and 900 of HD18O were analyzed and all the transitions were assigned. This paper focuses on lines intensities and comparisons with data from literature are presented. An average difference of 10% with HITRAN2008 database H218O line intensities is found with a maximum discrepancy of about 25% for the ν1–ν2 band.