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Ray City, NY, United States

Sagona J.A.,Rutgers University | Dukett J.E.,Adirondack Lakes Survey Corporation | Hawley H.A.,Rutgers University | Hawley H.A.,University of Texas at Tyler | Mazurek M.A.,Rutgers University
Journal of Chromatography A | Year: 2014

Cloud water samples from Whiteface Mountain, NY were used to develop a combined sampling and gas chromatography-mass spectrometric (GCMS) protocol for evaluating the complex mixture of highly polar organic compounds (HPOC) present in this atmospheric medium. Specific HPOC of interest were mono- and di keto-acids which are thought to originate from photochemical reactions of volatile unsaturated hydrocarbons from biogenic and manmade emissions and be a major fraction of atmospheric carbon. To measure HPOC mixtures and the individual keto-acids in cloud water, samples first must be derivatized for clean elution and measurement, and second, have low overall background of the target species as validated by GCMS analysis of field and laboratory blanks. Here, we discuss a dual derivatization method with PFBHA and BSTFA which targets only organic compounds that contain functional groups reacting with both reagents. The method also reduced potential contamination by minimizing the amount of sample processing from the field through the GCMS analysis steps. Once derivatized only gas chromatographic separation and selected ion monitoring (SIM) are needed to identify and quantify the polar organic compounds of interest. Concentrations of the detected total keto-acids in individual cloud water samples ranged from 27.8 to 329.3ngmL-1 (ppb). Method detection limits for the individual HPOC ranged from 0.17 to 4.99ngmL-1 and the quantification limits for the compounds ranged from 0.57 to 16.64ngmL-1. The keto-acids were compared to the total organic carbon (TOC) results for the cloud water samples with concentrations of 0.607-3.350mgL-1 (ppm). GCMS analysis of all samples and blanks indicated good control of the entire collection and analysis steps. Selected ion monitoring by GCMS of target keto-acids was essential for screening the complex organic carbon mixtures present at low ppb levels in cloud water. It was critical for ensuring high levels of quality assurance and quality control and for the correct identification and quantification of key marker compounds. © 2014 Elsevier B.V.

Aleksic N.,NY Environmental Conservation | Dukett J.E.,Adirondack Lakes Survey Corporation
Atmospheric Research | Year: 2010

Within non-precipitating clouds, total ionic content (TIC) of cloud droplets decreases with increasing liquid water content (LWC). However, this is not a simple inverse relationship. Instead, TIC has an exponential distribution with a parameter that is dependent on LWC. We demonstrate this finding using a long-term monitoring record (1994-2006) of cloud water chemistry measurements collected at the summit of Whiteface Mountain, NY. © 2010 Elsevier B.V.

Schwab J.J.,Albany State University | Casson P.,Albany State University | Brandt R.,Albany State University | Husain L.,Albany State University | And 7 more authors.
Aerosol and Air Quality Research | Year: 2016

Long-term records of condensed-phase chemical data are presented from the Adirondack Mountain region of northern New York, USA. These data records are particularly valuable due to the combinations of aerosol, cloud, and precipitation measurements. Objectives of the research and this overview paper include the evaluation of emission reductions of regulated air pollutants and the observed effects on measured deposition, as well as the implications of changing pollutant concentration levels on human health and climate. Summer season cloud chemistry and year-round wet deposition and particulate matter data from two stations on Whiteface Mountain are presented to highlight some of the research and monitoring activities at this mountain location. Clear decreases in the anion concentrations and increases in pH over the past two decades have been observed in cloud and precipitation results. Large decreases in aerosol sulfate (> 80%) and aerosol optical black carbon (> 60%) have been observed for these species over the nearly 40 year summit observatory data record for these measurements, and decreases in PM2.5 mass, sulfate, nitrate, and ammonium have also been recorded over the shorter 15 year period of measurement at the Marble Mountain Lodge level. The studies cited here highlight some of the past successes of air pollution regulation under the Clean Air Act and Amendments and pave the way for future progress in reducing air pollution. © Taiwan Association for Aerosol Research.

Dukett J.E.,Adirondack Lakes Survey Corporation | Aleksic N.,NY Environmental Conservation | Houck N.,Adirondack Lakes Survey Corporation | Snyder P.,Adirondack Lakes Survey Corporation | And 2 more authors.
Atmospheric Environment | Year: 2011

Fossil fuel combustion is the primary source of anthropogenic acidity in cloud water. Since 1994 there is a measurable decrease in hydrogen, sulfate, and nitrate ion concentrations in cloud water collected at Whiteface Mountain. In this paper we assess these changes from the point of view of progress toward clean air conditions. The cleanest clouds crossing Whiteface Mountain, those with the lowest total ion concentrations, are found to have pH values in the range 5.0-5.25. Furthermore, there is a linear relationship between pH, sulfate and nitrate ion concentrations in cloud water. With this in mind, we define clean cloud water values of sulfate, nitrate and hydrogen as mean concentrations observed in cloud water samples with pH in the range 5.0-5.25.We then compare mean annual values to clean air values to determine annual ratios. In 1994, ratios for SO42-, NO3- and H+ were respectively 26.9, 13.1 and 29.9 times above the clean air value. In 2009, the SO42-, NO3- and H+ corresponding ratios were 4.2, 2.7, and 4.8 times above the clean air value. In other words, comparison of the 1994 and 2009 results suggest reductions in anthropogenic concentrations of SO42-, NO3- and H+, by 84%, 79% and 84% respectively. To verify our approach, we have calculated corresponding changes in the aerosol SO42- ratio, with clean air concentrations equal to the natural background aerosol SO42- value used for the Regional Haze Rule. These results compared favorably to our cloud water SO42- ratio. © 2011 Elsevier Ltd.

Lawrence G.B.,U.S. Geological Survey | Dukett J.E.,Adirondack Lakes Survey Corporation | Houck N.,Adirondack Lakes Survey Corporation | Snyder P.,Adirondack Lakes Survey Corporation | Capone S.,Adirondack Lakes Survey Corporation
Environmental Science and Technology | Year: 2013

Increasing pH and decreasing Al in surface waters recovering from acidification have been accompanied by increasing concentrations of dissolved organic carbon (DOC) and associated organic acids that partially offset pH increases and complicate assessments of recovery from acidification. To better understand the processes of recovery, monthly chemistry from 42 lakes in the Adirondack region, NY, collected from 1994 to 2011, were used to (1) evaluate long-term changes in DOC and associated strongly acidic organic acids and (2) use the base-cation surplus (BCS) as a chemical index to assess the effects of increasing DOC concentrations on the Al chemistry of these lakes. Over the study period, the BCS increased (p < 0.01) and concentrations of toxic inorganic monomeric Al (IMAl) decreased (p < 0.01). The decreases in IMAl were greater than expected from the increases in the BCS. Higher DOC concentrations that increased organic complexation of Al resulted in a decrease in the IMAl fraction of total monomeric Al from 57% in 1994 to 23% in 2011. Increasing DOC concentrations have accelerated recovery in terms of decreasing toxic Al beyond that directly accomplished by reducing atmospheric deposition of strong mineral acids. © 2013 American Chemical Society.

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