A5022659330- Atmospheric chemistry and aerosols
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University of Calgary
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University of Guelph
2017
Memorial University of Newfoundland
2006
Stratford Hospital
1976
Bellevue Hospital Center
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American Geophysical Union
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University of Arizona
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ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOnline Sulfur-Isotope Determination Using an Elemental Analyzer Coupled to a Mass SpectrometerA. Giesemann, H.-J. Jaeger, A. L. Norman, H. R. Krouse, and W. BrandCite this: Anal. Chem. 1994, 66, 18, 2816–2819Publication Date (Print):September 15, 1994Publication History Published online1 May 2002Published inissue 15 September 1994https://pubs.acs.org/doi/10.1021/ac00090a005https://doi.org/10.1021/ac00090a005research-articleACS PublicationsRequest...
Abstract. Motivated by the need to predict how Arctic atmosphere will change in a warming world, this article summarizes recent advances made research consortium NETCARE (Network on Climate and Aerosols: Addressing Key Uncertainties Remote Canadian Environments) that contribute our fundamental understanding of aerosol particles as they relate climate forcing. The overall goal has been use an interdisciplinary approach encompassing extensive field observations range chemical transport, earth...
Abstract One year of aerosol particle observations from Alert, Nunavut shows that new formation (NPF) is common during clean periods the summertime Arctic associated with attendant low condensation sinks and presence methane sulfonic acid (MSA), a product atmospheric oxidation dimethyl sulfide (DMS). The time periods, defined using distribution refractory black carbon number concentrations, increase in frequency June through August as anthropogenic influence dwindles. During concentrations...
The recent decline in sea ice cover the Arctic Ocean could affect regional radiative forcing via changes ice–atmosphere exchange of dimethyl sulfide (DMS) and biogenic aerosols formed from its atmospheric oxidation, such as methanesulfonic acid (MSA). This study examines relationships between total extent north 70°N MSA measurement at Alert, Nunavut, during 1980–2009; Barrow, Alaska, 1997–2008; Ny‐Ålesund, Svalbard, for 1991–2004. During 1980–1989 1990–1997 periods, summer (July–August) June...
Abstract. Size-segregated aerosol sulfate concentrations were measured on board the Canadian Coast Guard Ship (CCGS) Amundsen in Arctic during July 2014. The objective of this study was to utilize isotopic composition address contribution anthropogenic and biogenic sources aerosols growth different size fractions atmosphere. Non-sea-salt is divided into using stable isotope apportionment techniques. A considerable amount average concentration fine with a diameter < 0.49 µm from (> 63...
Abstract. Dimethylsulfide (DMS), outgassed from ocean waters, plays an important role in the climate system, as it oxidizes to methane sulfonic acid (MSA) and sulfur dioxide (SO2), which can lead formation of sulfate aerosol. Newly formed aerosol resulting DMS oxidation may grow by condensation gases, in-cloud oxidation, coagulation sizes where they act cloud nuclei (CCN) influence properties. Under future global warming conditions, sea ice Arctic region is expected decline significantly,...
From July 1993 to September 1994, seasonal variations in the sources of SO 4 2− aerosols Arctic lower atmosphere at Alert, Canada, (82°30′N, 62°20′W) were investigated using sulphur isotope abundance as little 10 μg analyzed by combustion‐flow isotope‐ratio mass spectrometry. In conjunction with air trajectories and parallel measurements aerosol composition, composition was used discern . Total is composed sea‐salt , marine biogenic, nonmarine June through fraction biogenic non‐sea‐salt...
In the agriculture sector, crop production and on-farm fuel use are two main sources of greenhouse gas emissions (GHGs) apart from enteric fermentation. The application conventional synthetic fertilizer for can help to increase yields, but also results in nitrous oxide emissions, polluting waterways, deterioration soil health including damages structure, changes pH, as well decreases carbon content microbial diversity. Most farm machinery is powered by diesel which emits dioxide other air...
[1] Dimethyl sulfide (DMS) and its oxidation products, which have been proposed to provide a climate feedback mechanism by affecting aerosol cloud radiative properties, were measured on board the Canadian Coast Guard ship Amundsen in sampling campaigns Arctic fall of 2007 2008. DMS flux was calculated based surface water measurements yielded 0.1–2.6 μmol m−2 d−1 along Northwest Passage 0.2–1.3 Baffin Bay sulfur dioxide (SO2), methane sulfonic acid (MSA), sulfate aerosols also measured. The...
Abstract. Atmospheric dimethyl sulfide, DMS(g), is a climatically important sulfur compound and the main source of biogenic sulfate aerosol in Arctic atmosphere. DMS(g) production emission to atmosphere increase during summer due greater ice-free sea surface higher biological activity. We implemented Environment Climate Change Canada’s (ECCC) online air quality forecast model, GEM-MACH (Global Environmental Multiscale–Modelling Air CHemistry), compared model simulations with measurements...
Contributions to atmospheric sulphate aerosol and precipitation in the Fraser Valley at Saturna Island, Canada, from oxidation of biogenic dimethyl sulphide were determined using an isotopic mass balance approach. The S‐isotope composition sulphate, sulphur dioxide a variety industrial sources region investigated found have δ 34 S values ranging between −1.6 +9‰. Isotopic analysis suggests U.S. oil refinery and/or H 2 tidal flats on coast contributes load both summer winter. On average,...
Stable isotope compositions of hydrogen and oxygen for continental condensates are determined foremost by equilibrium kinetic fractionation during evaporation at the oceanic source regions. Subsequently they modified a series in-cloud processes, which include condensation possible admixture vapour from transpiration over continents. The effects on (δ2H) (δ18O) local precipitation discussed in this paper. Using Rayleigh model, described both constant stepwise fluxes. Further, deuterium...
Firn air and ice have been sampled analyzed for trace gases (CO 2 , N O, CH 4 CO) isotopes ( 14 C, 13 18 O of CO ; 3 H ice) at m intervals from the surface to depth closure 60 on Devon Island Ice Cap, a low‐elevation permanent glacier in Canadian Arctic Islands, investigate firn diffusion effects summer melting. The profile permeable includes 1963 thermonuclear peak 53.9 ± 1.5 m. twofold increase rapid decay that characterize recent atmospheric history provide robust scenario is used with...
Sulfur (S) isotopes have been used to apportion the amount of biogenic and anthropogenic sulfate in remote environments, an important parameter that is model global radiation budget. A key assumption apportionment calculations there little isotope selectivity as reduced compounds such dimethyl sulfide (DMS) are oxidized. This paper describes a method determine, for first time, S composition methanesulfonic acid (MSA), product DMS oxidation. The MSA was measured directly by EA-IRMS reference...
Agricultural soils are the dominant contributor to increases in atmospheric nitrous oxide (N 2 O). Few studies have investigated natural N and O isotopic composition of soil O. We collected gas samples using horizontal sampling tubes installed at successive depths under five contrasting agricultural crops (e.g., unamended alfalfa, fertilized cereal), tropospheric air samples. Mean δ 15 18 values ranged from −28.0 +8.9‰, +29.0 +53.6‰. The mean were +4.6 ± 0.7‰ +48.3 0.2‰, respectively. In...
Abstract The influence of frost flowers and seawater brine on ion chemistry in snow, snowpack, ice cores, aerosols is detected when a lower sulfate to sodium ratio than present polar regions. This evidence can be masked large amounts non‐sea‐salt are from other sources such as biogenic anthropogenic sulfate. Frost flower δ 34 S values were measured for the first time sulfates did not differ significantly sea salt +21‰. A method using stable isotopes introduced determine limit contributions...
Abstract. Maintaining consistent traceability of high-precision measurements CO2 isotopes is critical in order to obtain accurate atmospheric trends δ13C and δ18O (in CO2). Although a number laboratories/organizations around the world have been conducting baseline for several decades, reports on maintenance are rare. In this paper, principle an approach maintaining isotope (δ13C δ18O) described. The concept Big Delta introduced its role described discussed extensively. uncertainties...
The early atmospheric detection of carbon dioxide (CO2) leaks from capture and storage (CCS) sites is important both to inform remediation efforts build maintain public support for CCS in mitigating greenhouse gas emissions. A analysis system was developed assess the origin plumes air enriched CO2, as whether CO2 a site or oxidation compounds. measured O2 concentrations different plume samples relative background calculated differential concentration ratio (GDCR = −ΔO2/ΔCO2). experimental...