HITRAN2016 DATABASE PART II: OVERVIEW OF THE SPECTROSCOPIC PARAMETERS OF THE TRACE GASES

The 2016 edition of HITRAN database footnote{The HITRAN database is supported by the NASA AURA program grant NNX14AI55G and NASA PDART grant NNX16AG51G.} is available now footnote{I. E. Gordon, L. S. Rothman, et al., J Quant Spectrosc Radiat Transf 2017; submitted.}. This new edition of the database takes advantage of the new structure and can be accessed through HITRANonline (www.hitran.org) footnote{Hill C, et al., J Quant Spectrosc Radiat Transf 2013;130:51–61.}. _x000d_ _x000d_ The line-by-line lists for almost all of the trace atmospheric species were updated in comparison with the previous edition HITRAN2012. These extended update covers not only updating few transitions of the certain molecules, but also complete replacements of the whole line lists, and as well as introduction of new spectroscopic parameters for non-Voigt line shape. _x000d_ The new line lists for NH$_3$, HNO$_3$, OCS, HCN, CH$_3$Cl, C$_2$H$_2$, C$_2$H$_6$, PH$_3$, C$_2$H$_4$, CH$_3$CN, CF$_4$, C$_4$H$_2$, and SO$_3$ feature substantial expansion of the spectral and dynamic ranges in addition of the improved accuracy of the parameters for already existing lines. A semi-empirical procedure was developed to update the air-broadening and self-broadening coefficients of N$_2$O, SO$_2$, NH$_3$, CH$_3$Cl, H$_2$S, and HO$_2$. We draw particular attention to flaws in the commonly used expression $n_{air}=0.79n_{N_2}+0.21n_{O_2}$ to determine the air-broadening temperature dependence exponent in the power law from those for nitrogen and oxygen broadening. A more meaningful approach will be presented. _x000d_ The semi-empirical line width, pressure shifts and temperature-dependence exponents of CO, NH$_3$, HF, HCl, OCS, C$_2$H$_2$, SO$_2$ perturbed by H$_2$, He, and CO$_2$ have been added to the database based on the algorithm described in Wilzewski et al.footnote{Wilzewski JS,et al., J Quant Spectrosc Radiat Transf 2016;168:193–206.}. The new spectroscopic parameters for HT profile were implemented into the database for hydrogen moleculefootnote{Wcisło P, et al., J Quant Spectrosc Radiat Transf 2016;177:75–91.}