Absolute cross sections of ozone at atmospheric temperatures for the Wulf and the Chappuis bands

Abstract

Ozone absorption constitutes a variable background against which measurement of pollution is observed from satellites by the solar occultation technique. The temperature-altitude gradient of ozone spans the range 180-340 K. Laboratory measurements of ozone absorption at temperatures across this range are needed to calibrate spectroscopic remote sensing, but have yielded results in substantial disagreement with each other. This paper presents the first measurements of the variation of absorption cross-sections of ozone at temperatures from 144 to 300 K over the 9250-18 500 cm(-1) spectral region.

High spectral resolution ozone absorption cross-sections – Part 1: Measurements, data analysis and comparison with previous measurements around 293 K

“…In general, our new absorption cross-section measurements agree well with those obtained by Mauersberger (1992) andEl Helou et al (2005) at the selected wavelengths (within about 1 % or better). Our new data agree within 1 % or better for the broad region 510-680 nm with those reported by Burkholder and Talukdar (1994), which were absolutely scaled using the data of Anderson and Mauersberger (1992).…”

“…Measurements have been performed at single wavelengths in the absorption minimum between the Huggins and Chappuis bands and in the Wulf band by Axson et al (2011), Anderson and Mauersberger (1992), Enami et al (2004) andEl Helou et al (2005). These provide additional information for spectral regions where existing broadband datasets demonstrate strong disagreement or only a single broadband measurement is available.…”

“…Data of Anderson et al (1993) obtained with a tandem dual-beam spectrometer were absolutely calibrated using the absolute cross-section reported by Anderson and Mauersberger (1992). In addition to the El Helou et al (2005) data, there are measurements performed by Enami et al (2004) at two single wavelengths at 760 nm using the cavity ring-down technique (Fig. 8a).…”

“…The ACSO website also provides polynomial coefficients (quadratic fits) BP calc that have been calculated by Bass and Paur for the temperature dependence of the original data excluding the 218 K at air wavelengths . HITRAN 2008 also contains polynomial coefficients (BP HITRAN ); however, a few corrections were made on the original BP data: air-vacuum wavelength conversion according to Edlen's equation (Edlen, 1966) and wavelength shift. Using original BMD data at four temperatures (218, 228, 243, and 295 K), Liu et al (2007) derived polynomial coefficients for temperature dependence for vacuum wavelength scale (BMD calc ), making possible the interpolation/extrapolation of the cross-sections to any given temperature.…”

“…the full-width half-maximum (FWHM), from about 0.015 nm in the UV to 0.025 nm in the visible. The echelle spectrometer delivers data on air wavelength scale, which was converted into vacuum wavelength scale using Edlen's equation (Edlen, 1966). FT spectra were recorded at constant spectral resolution of 1 cm −1 in the UV and the visible, and 2 cm −1 in NIR spectral ranges (optical path difference 0.9 and 0.45, respectively) with a boxcar apodization.…”