1. ABSORPTION CROSS-SECTIONS IN HITRAN2016: MAJOR DATABASE UPDATE FOR ATMOSPHERIC, INDUSTRIAL, AND CLIMATE APPLICATIONS
ROMAN V KOCHANOV, IOULI E GORDON, LAURENCE S. ROTHMAN, Atomic and Molecular Physics, Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA; KEITH SHINE, Department of Chemistry, University of Reading, Reading, United Kingdom; STEVEN W. SHARPE, TIMOTHY J. JOHNSON, Chemical Physics and Analysis, Pacific Northwest National Laboratory, Richland, WA, USA; JEREMY J. HARRISON, Department of Physics and Astronomy, University of Leicester, Leicester, United Kingdom; PETER F. BERNATH, Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA, USA; TIMOTHY WALLINGTON, Research and Advanced Engineering, Ford Motor Company, Dearborn, MI, USA; MANFRED BIRK, GEORG WAGNER, Remote Sensing Technology Institute, DLR, Wessling, Germany; CHRISTIAN HILL, Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom;
International Symposium on Molecular Spectroscopy
72nd Meeting - June 19-23, Champaign-Urbana, Illinois

2. Introduction Line-by-line parameters can be absent or incomplete
Large polyatomic molecules (many normal modes, dense spectra, hard to analyze)
Can be used in radiative transfer models, RE calculations, climate change tracking…
Important to provide cross-sections in HITRAN covering wide spectral ranges and at diverse thermodynamic conditions

3. HITRAN cross-section format (.xsc)
ASCII text format: 100 bytes header and data
Header contains basic cross-section parameters
Negative part of the spectra is zeroed-out

4. Parameters for cross-section (T,p)-set

5. HITRAN2012 VS HITRAN2016
HITRAN2012 absorption cross-section part includes:
50 compounds
Contains halocarbons, hydrofluorocarbons, Sulfur- and fluorine-containing species, oxygenated and nitrogenated hydrocarbons
Atmospherically relevant temperature and pressure range (temperature K, pressure up to 760Torr)
Spectra measured in the IR and UV (some data up to cm-1)
FT-IR technique
cm-1 resolution spectra
broadened by air, N2, He, and pure

6. HITRAN2012 VS HITRAN2016 HITRAN2016 update features:
275 new molecules (=>325 in total)
2780 cross-section (T,p)-sets in total
Contains categorized compounds for remote sensing, environment monitoring, climate applications, industrial pollution tracking, instrument calibration…
Atmospherically relevant temperature and pressure range
(temperature K, pressure up to 760Torr)
Update contains spectra containing features in near, middle and far infrared.
Measurements:
CRDS (Ethane, 200 kHz resolution, Reed et Hodges. JQSRT 2015)
FTS ( cm-1 resolution)
Spectra broadened by air, N2, He, and pure

7. Molecule categorization

8. HITRANonline absorption cross-section search

9. HITRANonline absorption cross-section search
VALUE
TYPE
CFC-12
Acronym
CCl2F2
Formula
CAS
Dichlorodifluoromethane
Name
InChI=1S/CCl2F2/c2-1(3,4)5
InChI
PXBRQCKWGAHEHS-UHFFFAOYSA-N
InChiKey

10. HITRANonline absorption cross-section search

13. Bibliography in HTML
Bibliography in LaTeX

14. HITRAN2016 update sources: Pacific Northwest National Laboratory (PNNL)
~230 molecules in total, 1260 cross-section sets
Reactive compounds, industrial pollutants
15 out of 30 urban air TOCs / EPA, 2017
Diluted by N2, 760 Torr and 5/25/50C per molecule
0.112 cm-1 resolution, ~ cm-1 range, high S/N, composite spectra
Sharpe et al (original paper)
Johnson et al (biomass burning detection)
43 updated molecules
12 new molecules:
4-Methylvaleric acid, 4-Penten-1-ol, DL-Limonene, D-Limonene, 2,3-Dimethylfuran, 2,5-Dimethylfuran, 3,3-Demethyl-2-pentanol, Limonene oxide, Methyl 2-methylbutyrate, Menthol, 1-Penten-3-ol, Methyl vinyl ether

15. Example: acetaldehyde (CH3CHO)
Update for cross-sections for acetaldehyde. Comparison of three cross-cross sections from PNNL [1] (update) with corresponding data from HITRAN2012 [2] (calibrated with PNNL data).
[1] Sharpe SW, Johnson TJ et al. Gas-phase databases for quantitative infrared spectroscopy. Appl Spectrosc 2004;58:1452–61
[2] Tereszchuk KA, Bernath PF. Infrared absorption cross-sections for acetaldehyde 37 (CH3CHO) in the 3μm region. J Quant Spectrosc Radiat Transf 2011;112:990–3.

16. HITRAN2016 update sources: Halocarbons and related compounds review
Ø. Hodnebrog et al. Global warming potentials and radiative efficiencies of halocarbons and related compounds: A comprehensive review. Rev Geophys 2013;51:300–78
CFCs, HCFCs, HFCs, PFCs, and many other types of compounds + REs, GWPs/GTPs, lifetimes, etc.
cm-1 resolution
strong features in cm-1 range
120 molecules, 160 cross-section sets

17. Recently measured cross-sections
J.J. Harrison et al. CCl4, HFC-23, HCFC-22, HFC-134a, CFC-12
142 high-resolution (~0.015 cm-1) air-broadened cross-section temperature and pressure sets, FTS
intensities calibrated using data from NIST and PNNL
G. Wagner and M. Birk. Bromine nitrate (JQSRT 2016)
0.014 cm-1 resolution, 66 cross-sections sets broadened by air, v2 and v3 bands, FTS
Z. Reed, J. Hodges. Ethane (JQSRT 2015)
CRDS air and self-broadened spectra (x6), 200 KHz spectral resolution
45 cross-section sets for 19 halocarbons (in total), published in by Wallington et al, Godin et al., Le Bris et al., Rodriguez et al (see refs in the upcoming paper)

18. Evaluating cross-sections
All parameters are present (T,p,res., broad.)
Any similar data from another source?
Yes
Yes
Pick “best” cross-section T,p-set for each wavenumber range. Interpolate if grid is not equidistant.
Compare by a set of criteria. Not always possible!

19. Evaluating cross-sections example: CF4

20. Acknowledgements HITRAN group Data suppliers:
Keith Shine, University of Reading, UK
Steven Sharpe, Timothy Johnson, PNNL, USA
Tim Wallington, Ford Motor Company, USA
Jeremy Harrison, University of Leicester, UK
Manfred Birk, Georg Wagner, DLR, Germany
Joseph Hodges, Zachary Reed, NIST, USA
Funding: NASA PATM, PDART, AURA

21. Thanks for your attention!