This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is composed of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity. Moreover, molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth. Of considerable note, experimental IR cross-sections for almost 300 additional molecules important in different areas of atmospheric science have been added to the database. The compilation can be accessed through www.hitran.org. Most of the HITRAN data have now been cast into an underlying relational database structure that offers many advantages over the long-standing sequential text-based structure. The new structure empowers the user in many ways. It enables the incorporation of an extended set of fundamental parameters per transition, sophisticated line-shape formalisms, easy user-defined output formats, and very convenient searching, filtering, and plotting of data. A powerful application programming interface making use of structured query language (SQL) features for higher-level applications of HITRAN is also provided.

/pdf/the-hitran-2008-molecular-spectroscopic-database-1ud8clpej3.pdf

The HITRAN 2008 molecular spectroscopic database

Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui affronteremo l’attuale problema dei mutamenti climatici. Presentiamo il documento redatto, votato e pubblicato dall’Ipcc - Comitato intergovernativo sui cambiamenti climatici - che illustra la sintesi delle ricerche svolte su questo tema rilevante.

/pdf/climate-change-2007-the-physical-science-basis-1x93ttz9jt.pdf

Climate Change 2007: The Physical Science Basis.

This chapter should be cited as: Myhre, G., D. Shindell, F.-M. Bréon, W. Collins, J. Fuglestvedt, J. Huang, D. Koch, J.-F. Lamarque, D. Lee, B. Mendoza, T. Nakajima, A. Robock, G. Stephens, T. Takemura and H. Zhang, 2013: Anthropogenic and Natural Radiative Forcing. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Coordinating Lead Authors: Gunnar Myhre (Norway), Drew Shindell (USA)

Anthropogenic and Natural Radiative Forcing

http://joenschem.com/yahoo_site_admin/assets/docs/atkinson2000r.93190106.pdf

Atmospheric chemistry of VOCs and NOx

Atmospheric degradation of volatile organic compounds

The rate coefficient for the reaction of O(1D) with H2O (Reaction 1), whose value is critical for calculating production rates of the OH radical in the atmosphere, was measured over a range of atmospherically relevant temperatures. The temporal profile of O(3P) following photolytic production of O(1D) in the presence of water vapor was used to determine a temperature dependent value for k1 of (1.45 ± 0.34) × 10−10 exp((89 ± 65)/T) cm3 molecule−1 s−1, where the quoted errors are at the 95% confidence level, include estimated systematic errors and σA = AσlnA. In addition, ratios of rate coefficients for quenching of O(1D) by N2 and O2
				(k2 and k3) to that for Reaction 1 were determined to be k2/k1 = (0.13 ± 0.04) and k3/k1 = (0.19 ± 0.09) by measuring the relative OH concentration produced from Reaction 1 in the presence of various concentrations of N2 or O2. Combining our results of this work with previous measurements of k1, we recommend a value for k1 = (1.62 ± 0.27) × 10−10 exp((65 ± 50)/T) cm3 molecule−1 s−1, where the quoted errors are 95% confidence level, include estimated systematic errors and σA = AσlnA. Based on these results, the uncertainty in the calculated atmospheric OH production rate due to the uncertainty in these rate coefficients is reduced from ±50% to ±20%.

Measurement of the rate coefficient for the reaction of O(1D) with H2O and re-evaluation of the atmospheric OH production rate

[1] Measurements of particle nucleation following the gas phase oxidation of α-pinene and β-pinene are reported. Particle nucleation following ozonolysis and O3 plus OH initiated monoterpene oxidation was measured in a 70-L Teflon bag reactor over the temperature range 278 to 320 K. Particle concentration temporal profiles were measured for a range of initial monoterpene and ozone concentrations using ultrafine condensation particle counters. Profiles were interpreted using a coupled gas phase chemistry and kinetic multicomponent nucleation model to determine the molar yield of the nucleating species in the ozonolysis experiments to be 1 × 10−5 and 0.009, for α-pinene and β-pinene, respectively. OH initiated oxidation was found to increase the nucleator yield for α-pinene, approximately a factor of three, but not for β-pinene. The molar yield of condensable reaction products (vapor pressure < 20 ppt at 296 K) was determined to be 0.06 for both α-pinene and β-pinene and was independent of the oxidation source. Particle growth, which is determined by the condensable reaction products, was nearly temperature independent. Atmospheric box model calculations of nucleation and particle growth for α-pinene and β-pinene oxidation under typical tropospheric conditions are presented and showed that (1) nucleation can be significant under favorable conditions, (2) nucleation is dominated by OH initiated oxidation, and (3) the partitioning of the condensable monoterpene oxidation products made a significant contribution to the growth of atmospheric aerosol and was capable of explaining the observed particle growth rates commonly observed in remote forests.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2006JD007783

Particle nucleation following the O3 and OH initiated oxidation of α‐pinene and β‐pinene between 278 and 320 K

The kinetics of the reactions O(/sup 3/P/sub J/) + H/sub 2/O/sub 2/ ..-->.. products (k/sub 1/) and O(/sup 3/P/sub J/) + ozone (O/sub 3/) ..-->.. 2O/sub 2/ (k/sub 2/) have been investigated as a function of temperature over the temperature ranges 298 to 386 and 237 to 377 K, respectively. O(/sup 3/P/sub J/) was produced in the absence of other reactive free radicals by 532-nm pulsed laser photolysis of O/sub 3/ and detected by time-resolved resonance fluorescence spectroscopy. The following Arrhenius expressions adequately describe the experimental results: k/sub 1/ = (1.13 +- 0.54) x 10/sup -12/exp(-(2000 +- 160)/T) and k/sub 2/ = (5.6 +- 2.1) x 10/sup -12/exp(-1950 +- 110)/T) (units are cm/sup 3/ molecule/sup -1/s/sup -1/, errors are 2sigma). 6 figures, 4 tables.

Kinetics of O(/sup 3/P/sub J/) reactions with H/sub 2/O/sub 2/ and O/sub 3/

The UV absorption spectrum of Cl 2 O 3 between 220 and 320 nm was measured using time-resolved transient absorption. Cl 2 O 3 was produced following 193-nm pulsed laser photolysis of N 2 O/Cl 2 /OClO/He or CF 2 /Cl 2 /OClO/N 2 gas mixtures by reaction 1:ClO+OClO+M→Cl 2 O 3 +M. The absorption spectrum peaks at 267 nm with a cross section of (1.60 -0.22 +0.35 )×10 -17 cm 2 (2σ error limits including estimated systematic errors)

Kinetic, thermochemical, and spectroscopic study of chlorine oxide (Cl2O3)

The technique of pulsed laser photolysis/pulsed laser-induced fluorescence detection of CF[sub 3]O was used to study the stratospherically important reactions of CF[sub 3]O radicals with NO (k[sub 5]), O[sub 3] (k[sub 4]), and O[sub 2] (k[sub 6]) and that of CF[sub 3]-OO with NO (k[sub 2]) and O[sub 3](k[sub 3]). Over the temperature range 233-360, K, k[sub 5](T) = (3.34 [+-] 0.68) x 10[sup [minus]11] exp[(160 [+-] 45)/T] cm[sup 3] molecule[sup [minus]1] s[sup [minus]1]. At 298 K, k[sub 2] = (1.57 [+-] 0.38) x 10[sup [minus]11] cm[sup 3] molecule[sup [minus]1] s[sup [minus]1] in agreement with past work. The reactions of CF[sub 3]O and CF[sub 3]OO with O[sub 3] were found to be slow with rate coefficients at 298 K of k[sub 4] = (2.5[sub [minus]1.5][sup 0.7]) x 10[sup [minus]14] cm[sup 3] molecule[sup [minus]1] s[sup [minus]1] and k[sub 3] [le] 7 x 10[sup [minus]15] cm[sup 3] molecule[sup [minus]1] s[sup [minus]1], respectively. No reaction of CF[sub 3]O with O[sub 2] was observed at 298 or 373 K, leading to an upper limit of k[sub 6] [le] 4 x 10[sup [minus]17] cm[sup 3] molecule[sup [minus]1] s[sup [minus]1] at 373 K. The implications of these results to the chemistry of CF[sub 3]O[sub x] radicalsmore » and O[sub 3] in the stratosphere are discussed. 32 refs., 7 figs., 1 tab.« less

A. R. Ravishankara

Papers

Measurement of the rate coefficient for the reaction of O(1D) with H2O and re-evaluation of the atmospheric OH production rate

Particle nucleation following the O3 and OH initiated oxidation of α‐pinene and β‐pinene between 278 and 320 K

Kinetics of O(/sup 3/P/sub J/) reactions with H/sub 2/O/sub 2/ and O/sub 3/

Kinetic, thermochemical, and spectroscopic study of chlorine oxide (Cl2O3)

Kinetics of the reactions of CF3Ox radicals with NO, O3, and O2