The data describe density functional theory (DFT) calculations of the pH dependent reaction barriers for the hydrolysis of four different monoterpene nitrates. These data are used to predict experimental reactivities and determine the underlying chemical mechanism for organic nitrate hydrolysis. This dataset is associated with the following publication: Wang, Y., I. Piletic, M. Takeuchi, T. Xu, S. France, and N.L. Ng. Synthesis and Hydrolysis of Atmospherically Relevant Monoterpene-Derived Organic Nitrates. ENVIRONMENTAL SCIENCE & TECHNOLOGY. American Chemical Society, Washington, DC, USA, 55(21): 14595-14606, (2021).

The attached extensive computational chemistry dataset involves detailed electronic structure (density functional theory - DFT) and kinetic calculation (master equation formalism) outputs for the reactions of isoprene and first generation oxidants with the hydroxyl radical. There are a total of 9 tabs in the Excel spreadsheet. The first two tabs provide the potential energy surfaces (PESs) of the isoprene+OH and isopOOH+OH (1st generation oxidant) reactions. The PESs are zero-point energy corrected and obtained at the M062x/maug-cc-pVTZ level of DFT. The third tab provides the reaction barriers for first and second generation 1,5-hydrogen atom shifts for two different isoprene peroxy radical isomers with several different DFT methods. The fourth and fifth tabs provide microcanonical rate constants for the reactions of isoprene and isopOOH with OH respectively. The remaining tabs give the rate constants for the 1,5-H shifts for four different isoprene peroxy radicals. The rate constants are computed using the M062x density functional and an average of 4 different DFT methods given in tab 3 for comparison. The average values are reported as the final rate constants determined by computational methods. This dataset is associated with the following publication: Piletic, I., R. Howell, L. Bartolotti, T. Kleindienst, S. Kaushik, and E. Edney. Multigenerational Theoretical Study of Isoprene Peroxy Radical 1–5-Hydrogen Shift Reactions that Regenerate HOx Radicals and Produce Highly Oxidized Molecules. JOURNAL OF PHYSICAL CHEMISTRY A. American Chemical Society, Washington, DC, USA, 123(4): 906-919, (2019).

This dataset provides in situ concentrations of nitric oxide (NO), nitrogen dioxide (NO2), total reactive nitrogen oxides (NOy), and ozone (O3) measured by the NOAA Nitrogen Oxides and Ozone (NOyO3) 4-channel chemiluminescence (CL) instrument during airborne campaigns conducted by NASA's Atmospheric Tomography (ATom) mission. NOyO3 provides fast-response, specific, high precision, and calibrated measurements of nitrogen oxides and ozone at a spatial resolution of better than 100 m. ATom deploys an extensive gas and aerosol payload on the NASA DC-8 aircraft for systematic, global-scale sampling of the atmosphere, profiling continuously from 0.2 to 12 km altitude. Flights occurred in each of 4 seasons from 2016 to 2018. Flights originate from the Armstrong Flight Research Center in Palmdale, California, fly north to the western Arctic, south to the South Pacific, east to the Atlantic, north to Greenland, and return to California across central North America. ATom establishes a single, contiguous, global-scale dataset. This comprehensive dataset will be used to improve the representation of chemically reactive gases and short-lived climate forcers in global models of atmospheric chemistry and climate.

This dataset provides the mixing ratios of reactive nitrogen and halogen species measured by the NOAA Iodide Ion Time-of-Flight Chemical Ionization Mass Spectrometer (NOAA CIMS) during airborne campaigns conducted by NASA's Atmospheric Tomography (ATom) mission for ATom-3 and ATom-4 campaigns. The NOAA CIMS uses chemical ionization mass spectrometric detection of gas phase organic and inorganic analytes via I- adduct formation. Measurements for ATom include N2O5 (dinitrogen pentoxide), ClNO2 (chloro nitrite), Cl2 (Chlorine), HCOOH (formic acid), C2H4O3S (hydroperoxymethyl thioformate), BrCl (bromine monochloride), BrCN (cyanogen bromide), and BrO (bromine monoxide). ATom deploys an extensive gas and aerosol payload on the NASA DC-8 aircraft for systematic, global-scale sampling of the atmosphere, profiling continuously from 0.2-13 km altitude. This comprehensive dataset will be used to improve the representation of chemically reactive gases and short-lived climate forcers in global models of atmospheric chemistry and climate.

The TROPESS CrIS-JPSS1 L2 Peroxyacetyl Nitrate for Forward Stream, Summary Product contains the vertical distribution of the retrieved atmospheric state of peroxyacetyl nitrate (PAN), and formal uncertainties measured by the CrIS instrument on the JPSS-1 (NOAA-20) satellite. The forward stream standard product is global for the time period from 2021-04-01 to present. The NASA TRopospheric Ozone and Precursors from Earth System Sounding (TROPESS) project, uses an optimal estimation algorithm, known as the MUlti-SpEctra, MUlti-SpEcies, Multi-SEnsors (MUSES).The data files are written in the netCDF version 4 file format, and each file contains one day of data. The data have a spatial resolution of 14 km (CrIS nadir FOV), and are reported at 16 vertical levels from the surface to 0.1 hPa. The principal investigator for the TROPESS project is Kevin W. Bowman.

Data zip file contains the exact CMAQ code used by Wiser et al. in the development of CRACMM1AMORE. In addition, CMAQ predictions and AQS observations of formaldehyde and ozone appearing in Figure 8 are included as csv files. For information on CMAQ file conventions as well as site compare output for model/observation evaluation, see the linked github repository for CMAQ. Linked dois include the standard CMAQv5.3.3 code and AMORE supplementary files.

This data set provides global gridded estimates of atmospheric deposition of total inorganic nitrogen (N), NHx (NH3 and NH4+), and NOy (all oxidized forms of nitrogen other than N2O), in mg N/m2/year, for the years 1860 and 1993 and projections for the year 2050. The data set was generated using a global three-dimensional chemistry-transport model (TM3) with a spatial resolution of 5 degrees longitude by 3.75 degrees latitude (Jeuken et al., 2001; Lelieveld and Dentener, 2000). Nitrogen emissions estimates (Van Aardenne et al., 2001) and projection scenario data (IPCC, 1996; 2000) were used as input to the model. The model output grids were subdivided into 50 km x 50 km sub-grids to create spatially defined deposition maps. The gridded data were assigned to continental and marine regions using boundaries delineated on a world data coverage from ESRI (1993).The data are stored as ASCII text files (.txt), in tab delimited format. The data can be used to produce maps that illustrate both the temporal and spatial variability of atmospheric deposition of N, NHx, and NOy as well as the degree of alteration and regional heterogeneity in deposition through time. Nine data files are provided to produce the following maps:Global N Deposition (1860, 1993, and 2050)Global NHx Deposition (1860, 1993, and 2050)Global NOy Deposition (1860, 1993, and 2050).

The dataset was created by University of Houston. For details, please contact Jia Jung at helloiamjia@gmail.com. This dataset is associated with the following publication: Jung, J., Y. Choi, S. Mousavinezhad, D. Kang, J. Park, A. Pouyaei, M. Ghahremanloo, M. Momeni, and H. Kim. Changes in the ozone chemical regime over the contiguous United States inferred by the inversion of NOx and VOC emissions using satellite observation. Atmospheric Research. Elsevier Science BV, Amsterdam, NETHERLANDS, 270: 106076, (2022).

Oxidation of the monoterpene Δ3-carene (C10H16) is a potentially important and under-studied source of atmospheric secondary organic aerosol (SOA). We present chamber-based measurements of the speciated gas and particle phases during photochemical oxidation of Δ3-carene. We find evidence of highly oxidized organic molecules (HOM) in the gas phase and relatively low volatility SOA dominated by C7-C10 species. We then use computational methods to develop the first stages of a Δ3-carene photochemical oxidation mechanism and explain some of our measured compositions. We find that alkoxy bond scission of the cyclohexyl ring likely leads to efficient HOM formation, in line with previous studies. We also find a surprising role for the abstraction of primary hydrogens from methyl groups, which has been calculated to be rapid in the α-pinene system, and suggest more research is required to determine if this is more general to other systems and a feature of autoxidation. This work develops a more comprehensive view of Δ3-carene photochemical oxidation products via measurements and lays out a suggested mechanism of oxidation via computationally derived rate coefficients. This dataset is not publicly accessible because: Non-EPA data. It can be accessed through the following means: Please contact Joel Thornton at: thornton@atmos.uw.edu. Format: text files. This dataset is associated with the following publication: D'Ambro, E., N. Hyttinen, K. Møller, S. Iyer, R. Otkjær, D. Bell, J. Liu, F. Lopez-Hilfiker, S. Schobesberger, J. Shilling, A. Zelenyuk, H. Kjaergaard, J. Thornton, and T. Kurten. Pathways to highly oxidized products in the Δ3-Carene + OH system. ENVIRONMENTAL SCIENCE & TECHNOLOGY. American Chemical Society, Washington, DC, USA, 56(4): 2213-2224, (2022).