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.

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The HITRAN 2008 molecular spectroscopic database

Nitric oxide contrasts with most intercellular messengers because it diffuses rapidly and isotropically through most tissues with little reaction but cannot be transported through the vasculature due to rapid destruction by oxyhemoglobin. The rapid diffusion of nitric oxide between cells allows it to locally integrate the responses of blood vessels to turbulence, modulate synaptic plasticity in neurons, and control the oscillatory behavior of neuronal networks. Nitric oxide is not necessarily short lived and is intrinsically no more reactive than oxygen. The reactivity of nitric oxide per se has been greatly overestimated in vitro because no drain is provided to remove nitric oxide. Nitric oxide persists in solution for several minutes in micromolar concentrations before it reacts with oxygen to form much stronger oxidants like nitrogen dioxide. Nitric oxide is removed within seconds in vivo by diffusion over 100 microns through tissues to enter red blood cells and react with oxyhemoglobin. The direct toxicity of nitric oxide is modest but is greatly enhanced by reacting with superoxide to form peroxynitrite (ONOO-). Nitric oxide is the only biological molecule produced in high enough concentrations to out-compete superoxide dismutase for superoxide. Peroxynitrite reacts relatively slowly with most biological molecules, making peroxynitrite a selective oxidant. Peroxynitrite modifies tyrosine in proteins to create nitrotyrosines, leaving a footprint detectable in vivo. Nitration of structural proteins, including neurofilaments and actin, can disrupt filament assembly with major pathological consequences. Antibodies to nitrotyrosine have revealed nitration in human atherosclerosis, myocardial ischemia, septic and distressed lung, inflammatory bowel disease, and amyotrophic lateral sclerosis.

Nitric oxide, superoxide, and peroxynitrite: the good, the bad, and ugly.

Black carbon aerosol plays a unique and important role in Earth's climate system. Black carbon is a type of carbonaceous material with a unique combination of physical properties. This assessment provides an evaluation of black-carbon climate forcing that is comprehensive in its inclusion of all known and relevant processes and that is quantitative in providing best estimates and uncertainties of the main forcing terms: direct solar absorption; influence on liquid, mixed phase, and ice clouds; and deposition on snow and ice. These effects are calculated with climate models, but when possible, they are evaluated with both microphysical measurements and field observations. Predominant sources are combustion related, namely, fossil fuels for transportation, solid fuels for industrial and residential uses, and open burning of biomass. Total global emissions of black carbon using bottom-up inventory methods are 7500 Gg yr−1 in the year 2000 with an uncertainty range of 2000 to 29000. However, global atmospheric absorption attributable to black carbon is too low in many models and should be increased by a factor of almost 3. After this scaling, the best estimate for the industrial-era (1750 to 2005) direct radiative forcing of atmospheric black carbon is +0.71 W m−2 with 90% uncertainty bounds of (+0.08, +1.27) W m−2. Total direct forcing by all black carbon sources, without subtracting the preindustrial background, is estimated as +0.88 (+0.17, +1.48) W m−2. Direct radiative forcing alone does not capture important rapid adjustment mechanisms. A framework is described and used for quantifying climate forcings, including rapid adjustments. The best estimate of industrial-era climate forcing of black carbon through all forcing mechanisms, including clouds and cryosphere forcing, is +1.1 W m−2 with 90% uncertainty bounds of +0.17 to +2.1 W m−2. Thus, there is a very high probability that black carbon emissions, independent of co-emitted species, have a positive forcing and warm the climate. We estimate that black carbon, with a total climate forcing of +1.1 W m−2, is the second most important human emission in terms of its climate forcing in the present-day atmosphere; only carbon dioxide is estimated to have a greater forcing. Sources that emit black carbon also emit other short-lived species that may either cool or warm climate. Climate forcings from co-emitted species are estimated and used in the framework described herein. When the principal effects of short-lived co-emissions, including cooling agents such as sulfur dioxide, are included in net forcing, energy-related sources (fossil fuel and biofuel) have an industrial-era climate forcing of +0.22 (−0.50 to +1.08) W m−2 during the first year after emission. For a few of these sources, such as diesel engines and possibly residential biofuels, warming is strong enough that eliminating all short-lived emissions from these sources would reduce net climate forcing (i.e., produce cooling). When open burning emissions, which emit high levels of organic matter, are included in the total, the best estimate of net industrial-era climate forcing by all short-lived species from black-carbon-rich sources becomes slightly negative (−0.06 W m−2 with 90% uncertainty bounds of −1.45 to +1.29 W m−2). The uncertainties in net climate forcing from black-carbon-rich sources are substantial, largely due to lack of knowledge about cloud interactions with both black carbon and co-emitted organic carbon. In prioritizing potential black-carbon mitigation actions, non-science factors, such as technical feasibility, costs, policy design, and implementation feasibility play important roles. The major sources of black carbon are presently in different stages with regard to the feasibility for near-term mitigation. This assessment, by evaluating the large number and complexity of the associated physical and radiative processes in black-carbon climate forcing, sets a baseline from which to improve future climate forcing estimates.

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Bounding the role of black carbon in the climate system: A scientific assessment

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

Temperature Dependent Rate Coefficient of the Cl+ClNO2 Reaction,

Product Analysis of the OH + NO2 + M Reaction

Rate coefficients for the reaction, OH + CCl3CHO (chloral) → products (k5), were measured over the temperature range 233−415 K using the pulsed laser photolysis-laser-induced fluorescence method, and were determined to be k5(T) = (1.79 ± 0.17) × 10-12 exp[−(240 ± 60)/T] cm3 molecule-1 s-1. The quoted uncertainties are at the 95% confidence level with σA = AσlnA, and include estimated systematic errors. Our results are compared with those from previous work and the differences are discussed. UV absorption cross sections of CCl3CHO were measured between 200 and 345 nm and over the temperature range 240−360 K. These measurements are in good agreement with previously reported values. The quantum yields for O, H, and Cl atoms in CCl3CHO photolysis were measured via atomic resonance fluorescence detection following pulsed excimer photolysis. Upper limits for the O atom quantum yield in CCl3CHO photolysis at 308 and 248 nm were measured to be <0.01 and <0.02, respectively. The H atom quantum yields in CCl3CHO ph...

Quantification of the Tropospheric Removal of Chloral (CCl3CHO): Rate Coefficient for the Reaction with OH, UV Absorption Cross Sections, and Quantum Yields

Reactions of O(3P) with Alkyl Iodides: Rate Coefficients and Reaction Products.

Absolute ClO radical product yields in the gas-phase reactions of O((1)D) with Cl(2), HCl, CCl(4), CHCl(3), CH(2)Cl(2), CH(3)Cl, CFCl(3), CF(2)Cl(2), CF(3)Cl, CHFCl(2), and CHF(2)Cl are reported. Product yields were measured using pulsed-laser photolysis of O(3) to produce O((1)D) in the presence of excess reactant combined with dual wavelength differential cavity ring-down spectroscopic detection of the ClO radical. ClO radical absorption cross sections for the A(2)Π(v = 10) ← X(2)Π(v = 0) transition band head near 280 nm were determined between 200 and 296 K as part of this work. The ClO product yields obtained at room temperature were Cl(2) (0.77 ± 0.10), HCl (0.20 ± 0.04), CCl(4) (0.79 ± 0.04), CHCl(3) (0.77 ± 0.04), CH(2)Cl(2) (0.73 ± 0.04), CH(3)Cl (0.46 ± 0.06), CFCl(3) (0.79 ± 0.04), CF(2)Cl(2) (0.76 ± 0.06), CF(3)Cl (0.82 ± 0.06), CHFCl(2) (0.73 ± 0.05), and CHF(2)Cl (0.56 ± 0.03), where the quoted error limits are 2σ of the measurement precision. ClO product yields in the O((1)D) + Cl(2) and CFCl(3) reactions were found to be independent of temperature between 200 and 296 K, within the precision of the measurements. The absolute ClO yields obtained in this study are compared with previously reported values determined using relative and indirect methods.

James B. Burkholder

Papers

Temperature Dependent Rate Coefficient of the Cl+ClNO2 Reaction,

Product Analysis of the OH + NO2 + M Reaction

Quantification of the Tropospheric Removal of Chloral (CCl3CHO): Rate Coefficient for the Reaction with OH, UV Absorption Cross Sections, and Quantum Yields

Reactions of O(3P) with Alkyl Iodides: Rate Coefficients and Reaction Products.

ClO radical yields in the reaction of O(1D) with Cl2, HCl, chloromethanes, and chlorofluoromethanes.