Near-infrared water vapour self-continuum at close to room temperature

Ptashnik, Igor V.; Petrova, T. M.; Ponomarev, Yu. N.; Shine, Keith P.; Solodov, A. A.; Solodov, A. M.

doi:10.1016/j.jqsrt.2013.02.016

Cited by 55 publications

(108 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As illustrated in Fig. 6 The strong disagreement with FTS measurements (Ptashnik et al, 2011a(Ptashnik et al, , 2013(Ptashnik et al, , 2015 has been discussed by Shine et al, 2016 andCampargue et al 2016. The measurement of a very small variation of a FTS spectrum baseline induced by the injection of water vapor in an absorption cell requires very high baseline stability during the entire measurement period.…”

Section: Resultsmentioning

confidence: 98%

“…al., 2013; 2015), obtained with a pathlength of 612 m at 289.5 and 287 K, respectively, (iii) the FTS dataset obtained at NIST by Baranov and Lafferty (2011) with a 100 m pathlength between 311 and 363 K. Finally, Burch and Alt (1984) reported continuum measurements in the center of the window using a grating spectrograph and an optical configuration aiming to minimize the spectra baseline drifts. Campargue et al, 2016;Richard et al, 2017;this work); by FTS from Baranov and Lafferty (2011), light blue circles, from CAVIAR (black squares; Ptashnik et al, 2011a), from Tomsk2013 (orange circles; Ptashnik et al, 2013), from Tomsk2015 (orange circles; Ptashnik et al, 2015) and with a grating spectrograph by Burch and Alt (1984) The evolution of the MT_CKD model in the 4.0 µm over the last ten years is illustrated by the 2.4, 2.8, 3.0 and 3.2 versions plotted in Fig. 3.…”

Section: Comparison To Literaturementioning

confidence: 99%

“…The two last versions of the MT_CKD model (V3.0 and V3.2, black and red solid lines, respectively) are compared to the laser based 10 measurements (red circles), to the FTS results obtained in Tomsk (Ptashnik et al, 2013(Ptashnik et al, , 2015; green and orange circles) or by the CAVIAR consortium (Ptashnik et al, 2011a) (black squares). The 30-50 % error bars on the Tomsk2015 FTS values and the small error bars on our laser based values are not plotted for clarity.…”

Section: Comparison To Literaturementioning

confidence: 99%

See 2 more Smart Citations

The water vapor self-continuum absorption in the infrared atmospheric windows: New laser measurements near 3.3 μm and 2.0 μm

Lechevallier¹,

Vasilchenko²,

Grilli³

et al. 2017

Preprint

View full text Add to dashboard Cite

Abstract. The amplitude, the temperature dependence and the physical origin of the water vapor absorption continuum are a long standing issue in molecular spectroscopy with direct impact in atmospheric and planetary sciences. In the recent years, we have determined the self-continuum absorption of water vapor at different spectral points of the atmospheric windows at 4.0, 2.1, 1.6 and 1.25 µm, by highly sensitive cavity enhanced laser techniques. These accurate experimental constraints have been used to adjust the last version (V3.2) of the semi-empirical MT_CKD model (Mlawer-Tobin_Clough-Kneizys-Davies) 15 widely incorporated in atmospheric radiative transfer codes. In the present work, the self-continuum cross-sections, C S , are newly determined at 3.3 µm (3007 cm -1 ) and 2.0 µm (5000 cm -1 ) by optical-feedback-cavity enhanced absorption spectroscopy (OFCEAS) and cavity ring-down spectroscopy (CRDS), respectively. These new data allow completing the spectral coverage of the 4.0 and 2.1 µm windows, respectively, and testing the recently released V3.2 version of the MT_CKD3 continuum. By complementing high temperature literature data to the present data, the temperature dependence 20 of the self continuum is presented.

show abstract

Section: Resultsmentioning

confidence: 98%

Section: Comparison To Literaturementioning

confidence: 99%

Section: Comparison To Literaturementioning

confidence: 99%

See 1 more Smart Citation

The water vapor self-continuum absorption in the infrared atmospheric windows: New laser measurements near 3.3 μm and 2.0 μm

Lechevallier¹,

Vasilchenko²,

Grilli³

et al. 2017

Preprint

View full text Add to dashboard Cite

show abstract

“…Paynter and Ramaswamy (2012) showed that the water vapor continuum could result in between 1.1 and 3.2 W m −2 additional clear-sky absorption of solar radiation globally. According to Paynter and Ramaswamy (2014), this sizable range is due to fairly large measurement uncertainties in the shortwave near-infrared window regions (Ptashnik et al, 2004(Ptashnik et al, , 2011(Ptashnik et al, , 2013Paynter et al, 2007Paynter et al, , 2009Lafferty, 2011, 2012;Mondelain et al, 2013). After the inclusion of a modified parameterization for the shortwave water vapor continuum (BPS-MTCKD 2.0) to the Geophysical Fluid Dynamics Laboratory (GFDL) global model, Paynter and Ramaswamy (2014) found that the surface en-ergy budget adjusted predominantly through a decrease in both surface latent and sensible heat.…”

Section: Introductionmentioning

confidence: 99%

“…On the other side, there have been many laboratory studies in the NIR range. Laboratory experiments using Fourier transform infrared (FTIR) spectrometry and large cells have shown that the self-and foreign continuum within the windows was found to be significantly stronger than given by MT_CKD (Baranov and Lafferty, 2011;Ptashnik et al, 2011Ptashnik et al, , 2012Ptashnik et al, , 2013. Another issue is that laboratory measurements performed by different techniques have yielded too inconsistent results.…”

Section: Introductionmentioning

confidence: 99%

The Zugspitze radiative closure experiment for quantifying water vapor absorption over the terrestrial and solar infrared – Part 1: Setup, uncertainty analysis, and assessment of far-infrared water vapor continuum

2016

View full text Add to dashboard Cite

Abstract. Quantitative knowledge of water vapor radiative processes in the atmosphere throughout the terrestrial and solar infrared spectrum is still incomplete even though this is crucial input to the radiation codes forming the core of both remote sensing methods and climate simulations. Beside laboratory spectroscopy, ground-based remote sensing field studies in the context of so-called radiative closure experiments are a powerful approach because this is the only way to quantify water absorption under cold atmospheric conditions. For this purpose, we have set up at the Zugspitze (47.42 • N, 10.98 • E; 2964 m a.s.l.) a long-term radiative closure experiment designed to cover the infrared spectrum between 400 and 7800 cm −1 (1.28-25 µm). As a benefit for such experiments, the atmospheric states at the Zugspitze frequently comprise very low integrated water vapor (IWV; minimum = 0.1 mm, median = 2.3 mm) and very low aerosol optical depth (AOD = 0.0024-0.0032 at 7800 cm −1 at air mass 1). All instruments for radiance measurements and atmospheric-state measurements are described along with their measurement uncertainties. Based on all parameter uncertainties and the corresponding radiance Jacobians, a systematic residual radiance uncertainty budget has been set up to characterize the sensitivity of the radiative closure over the whole infrared spectral range. The dominant uncertainty contribution in the spectral windows used for far-infrared (FIR) continuum quantification is from IWV uncertainties, while T profile uncertainties dominate in the mid-infrared (MIR). Uncertainty contributions to near-infrared (NIR) radiance residuals are dominated by water vapor line parameters in the vicinity of the strong water vapor bands. The window regions in between these bands are dominated by solar Fourier transform infrared (FTIR) calibration uncertainties at low NIR wavenumbers, while uncertainties due to AOD become an increasing and dominant contribution towards higher NIR wavenumbers. Exceptions are methane or nitrous oxide bands in the NIR, where the associated line parameter uncertainties dominate the overall uncertainty.As a first demonstration of the Zugspitze closure experiment, a water vapor continuum quantification in the FIR spectral region (400-580 cm −1 ) has been performed. The resulting FIR foreign-continuum coefficients are consistent with the MT_CKD 2.5.2 continuum model and also agree with the most recent atmospheric closure study carried out in Antarctica. Results from the first determination of the NIR water vapor continuum in a field experiment are detailed in a companion paper (Reichert and Sussmann, 2016) while a novel NIR calibration scheme for the underlying FTIR measurements of incoming solar radiance is presented in another companion paper .

show abstract

Temperature dependence of the water vapor self‐continuum by cavity ring‐down spectroscopy in the 1.6 µm transparency window

et al. 2014

View full text Add to dashboard Cite

The very weak water vapor self-continuum has been investigated by high-sensitivity cavity ring-down spectroscopy in the 1.6 μm window at five temperatures between 302 K and 340 K. The absorption cross sections, C s (ν, T), were retrieved for 10 selected wave numbers from a fit of the absorption coefficients measured in real time during pressure ramps, after subtraction of the contributions of the local water monomer lines and of water adsorbed on the cell mirrors. The values measured between 5875 and 6665 cm À1 range between 1.5 × 10 À25 and 2 × 10 À24 cm 2 mol À1 atm À1 with a minimum around 6300 cm À1 .At 302 K, an agreement within 50% is observed over the whole window with the cross sections provided by the MT_CKD V2.5 model. Nevertheless, while our measurements show that the C s (ν, T) decrease from 302 K to 340 K is no more than 50% for all our selected wave numbers, the MT_CKD V2.5 model predicts a much more pronounced temperature dependence in the center of the window, the agreement being better on the edges of the window. The obtained results are discussed in relation with theoretical modeling of the water vapor self-continuum as far wings of monomer lines or water dimer absorption. For potential atmospheric applications, cross sections are provided at each temperature with a sampling step of 10 cm À1for the entire 5850-6700 cm À1 range.

show abstract

Near-infrared water vapour self-continuum at close to room temperature

Cited by 55 publications

References 32 publications

The water vapor self-continuum absorption in the infrared atmospheric windows: New laser measurements near 3.3 μm and 2.0 μm

The water vapor self-continuum absorption in the infrared atmospheric windows: New laser measurements near 3.3 μm and 2.0 μm

The Zugspitze radiative closure experiment for quantifying water vapor absorption over the terrestrial and solar infrared – Part 1: Setup, uncertainty analysis, and assessment of far-infrared water vapor continuum

Temperature dependence of the water vapor self‐continuum by cavity ring‐down spectroscopy in the 1.6 µm transparency window

Contact Info

Product

Resources

About