Water vapor absorption between 5690 and 8340 cm−1: Accurate empirical line centers and validation tests of calculated line intensities

Abstract

An accurate empirical list of about 58000 transitions is constructed for natural water in the 5690-8340 cm-1 near infrared region (1.71-1.20 µm). The new list represents an updated version of the list reported in S.

The 2020 edition of the GEISA spectroscopic database

“…GEISA-2020 was updated using line intensities, air-broadening and -shifting coefficients provided from Mikhailenko et al [12], whereas the line positions were refined using the most recent version of their line list [13]. Note that local discrepancies due to erroneous broadening values of some H2O lines were found in these line lists and in GEISA-2015 (see for example residuals of the H2O line at 7804.6092 cm -1 in section 3.1.1), these lines were corrected in GEISA-2020 with calculated air-broadening parameters from Vispoel et al [14,15] were used to correct the incriminated lines (see details below).…”

“…Following the data update made for H2O (cf. previous section), the HDO linelist was also updated using line intensities and air-broadening and -shifting coefficients provided by Mikhailenko et al [12], and line positions which were refined using the most recent version of their line list [13]. As a result, 17,015 lines were updated in GEISA-2020 (from which 4468 are new lines not referenced in GEISA-2015).…”

“…As stated in section 2.1.1.1, the major update on H2 16 O was based on the work of Mikhailenko et al [12] (referenced as Mikhailenko 2016 in the following), who published a linelist of H2O parameters between 5830 and 8340 cm -1 based on a collection of several data. More recently they published refined line positions and shifts with respect to their former linelist [13] (included in GEISA-2020 update). Although much of these new data helped to improve line parameters in the GEISA database, the validation process using SPARTE based on TCCON observations highlighted a few remaining issues or artefacts in the SWIR domain.…”

“…Other parameters were updated using the data from references [12] and [13]. Finally, Figure 9 presents comparisons of the 'calc-obs' residuals obtained from the three different spectroscopic line lists in the 6631.5-6632.5 cm -1 , 7804-7805 cm -1 and 7850.5-7851.5 cm -1 regions, and the corresponding TCCON observations.…”

Validation of spectroscopic data in the 1.27 µm spectral region by comparisons with ground-based atmospheric measurements

“…Tests were also made with the most recent data of H2O in the 2019 version of the GEISA database [39]. In this spectral region, the GEISA2019 was updated using line intensities and air-broadening and -shifting coefficients provided in the H2O line list from Mikhailenko et al [40], whereas the line positions were refined using [41]. Note that local discrepancies due to erroneous broadening values of some H2O lines were identified in [40] and GEISA2015 (for the H2O line at 7804.6092 cm -1 for example), and some air-broadening parameters from GEISA2011 were reintroduced in GEISA2019.…”