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Full-Text Articles in Chemistry
Potentially Massive And Global Non-Pyrogenic Production Of Condensed "Black" Carbon Through Biomass Oxidation, Aleksandar I. Goranov, Hongmei Chen, Jianshu Duan, Satish C. B. Myneni, Patrick G. Hatcher
Potentially Massive And Global Non-Pyrogenic Production Of Condensed "Black" Carbon Through Biomass Oxidation, Aleksandar I. Goranov, Hongmei Chen, Jianshu Duan, Satish C. B. Myneni, Patrick G. Hatcher
Chemistry & Biochemistry Faculty Publications
With the increased occurrences of wildfires worldwide, there has been an increase in scientific interest surrounding the chemistry of fire-derived "black" carbon (BC). Traditionally, wildfire research has assumed that condensed aromatic carbon (ConAC) is exclusively produced via combustion, and thus, ConAC is equated to BC. However, the lack of correlations between ConAC in soils or rivers and wildfire history suggests that ConAC may be produced non-pyrogenically. Here, we show quantitative evidence that this occurs during the oxidation of biomass with environmentally ubiquitous hydroxyl radicals. Pine wood boards exposed to iron nails and natural weather conditions for 12 years yielded a …
Iron Speciation In Pm2.5 From Urban, Agriculture, And Mixed Environments In Colorado, Usa, Joseph R. Salazar, David J. Pfotenhauer, Frank Leresche, Fernando L. Rosario-Ortiz, Michael P. Hannigan, Sirine C. Fakra, Brian Majestic
Iron Speciation In Pm2.5 From Urban, Agriculture, And Mixed Environments In Colorado, Usa, Joseph R. Salazar, David J. Pfotenhauer, Frank Leresche, Fernando L. Rosario-Ortiz, Michael P. Hannigan, Sirine C. Fakra, Brian Majestic
Chemistry and Biochemistry: Faculty Scholarship
Atmospheric iron solubility varies depending on whether the particles are collected in rural or urban areas, with urban areas showing increased iron solubility. In this study, we investigate if the iron species present in different environments affects its ultimate solubility. Field data are presented from the Platte River Air Pollution and Photochemistry Experiment (PRAPPE), aimed at understanding the interactions between organic carbon and trace elements in atmospheric particulate matter (PM). 24-hr PM2.5 samples were collected during the summer and winter (2016–2017), at three different sites on the Eastern Colorado plains: an urban, agricultural, and a mixed site. Downtown Denver had …
Phosgene In The Upper Troposphere And Lower Stratosphere: A Marker For Product Gas Injection Due To Chlorine-Containing Very Short Lived Substances, Jeremy J. Harrison, Martyn P. Chipperfield, Ryan Hossaini, Christopher D. Boone, Sandip Dhomse, Wuhu Feng, Peter F. Bernath
Phosgene In The Upper Troposphere And Lower Stratosphere: A Marker For Product Gas Injection Due To Chlorine-Containing Very Short Lived Substances, Jeremy J. Harrison, Martyn P. Chipperfield, Ryan Hossaini, Christopher D. Boone, Sandip Dhomse, Wuhu Feng, Peter F. Bernath
Chemistry & Biochemistry Faculty Publications
Abstract: Phosgene in the atmosphere is produced via the degradation of carbon tetrachloride, methyl chloroform, and a number of chlorine‐containing very short lived substances (VSLS). These VSLS are not regulated by the Montreal Protocol even though they contribute to stratospheric ozone depletion. While observations of VSLS can quantify direct stratospheric source gas injection, observations of phosgene in the upper troposphere/lower stratosphere can be used as a marker of product gas injection of chlorine‐containing VSLS. In this work we report upper troposphere/lower stratosphere measurements of phosgene made by the ACE‐FTS (Atmospheric Chemistry Experiment Fourier Transform Spectrometer) instrument and compare with results …
New And Improved Infra-Red Absorption Cross Sections And Ace-Fts Retrievals Of Carbon Tetrachloride (Ccl4), Jeremy J. Harrison, Christopher D. Boone, Peter F. Bernath
New And Improved Infra-Red Absorption Cross Sections And Ace-Fts Retrievals Of Carbon Tetrachloride (Ccl4), Jeremy J. Harrison, Christopher D. Boone, Peter F. Bernath
Chemistry & Biochemistry Faculty Publications
Carbon tetrachloride (CCl4) is one of the species regulated by the Montreal Protocol on account of its ability to deplete stratospheric ozone. As such, the inconsistency between observations of its abundance and estimated sources and sinks is an important problem requiring urgent attention (Carpenter et al., 2014) [5]. Satellite remote-sensing has a role to play, particularly limb sounders which can provide vertical profiles into the stratosphere and therefore validate stratospheric loss rates in atmospheric models. This work is in two parts. The first describes new and improved high-resolution infra-red absorption cross sections of carbon tetrachloride/dry synthetic air over …
Late Holocene Climate And Environmental Reconstruction Derived From The Asian Ice Core Array (Aica), Bjorn Grigholm
Late Holocene Climate And Environmental Reconstruction Derived From The Asian Ice Core Array (Aica), Bjorn Grigholm
Electronic Theses and Dissertations
Recent climate change has impacted natural and human systems across the Earth, emphasizing the need for greater understanding of both the existing and changing natural and anthropogenic forcing mechanisms and subsequent responses of the Earth’s climate system. High-resolution, multi-parameter ice core records retrieved and analyzed from two Asian Ice Core Array (AICA) sites, Geladaindong (central Tibetan Plateau) and Inilchek (central Tien Shan) were utilized to reconstruct atmospheric chemical concentrations and composition over the past ~100-500 years, improving the understanding of late Holocene climate and environmental variability in Asia. Both ice cores were analyzed for major and trace elements, major soluble …
Atmospheric Effects Of Energetic Particle Precipitation In The Arctic Winter 1978-1979 Revisted, L. A. Holt, C. E. Randall, V. L. Harvey, E. E. Remsberg, G. P. Stiller, B. Funke, P. F. Bernath, K. A. Walker
Atmospheric Effects Of Energetic Particle Precipitation In The Arctic Winter 1978-1979 Revisted, L. A. Holt, C. E. Randall, V. L. Harvey, E. E. Remsberg, G. P. Stiller, B. Funke, P. F. Bernath, K. A. Walker
Chemistry & Biochemistry Faculty Publications
[1] The Limb Infrared Monitor of the Stratosphere (LIMS) measured polar stratospheric enhancements of NO2 mixing ratios due to energetic particle precipitation (EPP) in the Arctic winter of 1978–1979. Recently reprocessed LIMS data are compared to more recent measurements from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) and the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) to place the LIMS measurements in the context of current observations. The amount of NOx (NO + NO2) entering the stratosphere that has been created by EPP in the mesosphere and lower thermosphere (EPP-NOx) has been quantified …
Observation Of Sulfate Aerosols And So₂ From The Sarychev Volcanic Eruption Using Data From The Atmospheric Chemistry Experiment (Ace), D. Doeringer, A. Eldering, C. D. Boone, G. González Abad, P. F. Bernath
Observation Of Sulfate Aerosols And So₂ From The Sarychev Volcanic Eruption Using Data From The Atmospheric Chemistry Experiment (Ace), D. Doeringer, A. Eldering, C. D. Boone, G. González Abad, P. F. Bernath
Chemistry & Biochemistry Faculty Publications
[1] Infrared spectra measured by the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) on the SCISAT satellite were used to analyze the Sarychev volcanic aerosol after the eruption in June 2009. Evidence of the Sarychev eruptions was first detected in July 2009 from enhanced SO2 concentrations and atmospheric extinction. By February 2010, the atmosphere had returned to pre-Sarychev conditions. In July 2009, the volcanic plume was found between 8.5 km and 17.5 km in altitude at mid- and high latitudes (55°N–70°N). The first SO2 and sulfate aerosol retrievals carried out using the infrared solar occultation spectra recorded with …