Composition analyses of size‐resolved aerosol samples taken from aircraft downwind of Kuwait, spring 1991

Abstract

Analyses are reported for eight aerosol samples taken from the National Center for Atmospheric Research Electra typically 200 to 250 km downwind of Kuwait between May 19 and June 1, 1991. Aerosols were separated into fine (Dp < 2.5 μm) and coarse (2.5 < Dp 10 μm) particles for optical, gravimetric, X ray and nuclear analyses, yielding information on the morphology, mass, and composition of aerosols downwind of Kuwait. The mass of coarse aerosols ranged between 60 and 1971 μg/m3 and, while dominated by soil derived aerosols, contained considerable content of sulfates and salt (NaCl) and soot in the form of fluffy agglomerates. The mass of fine aerosols varied between 70 and 785 μg/3, of which about 70% was accounted for via compositional analyses performed in vacuum. While most components varied greatly from flight to flight, organic matter and fine soils each accounted for about 1/4 of the fine mass, while salt and sulfates contributed about 10% and 7%, respectively. The Cl/S ratios were remarkable constant, 2.4 ± 1.2 for coarse particles and 2.0 ± 0.2 for fine particles, with one flight deleted in each case. Vanadium, when observed, ranged from 9 to 27 ng/m3, while nickel ranged from 5 to 25 ng/m3. In fact, fine sulfates, vanadium, and nickel occurred in levels typical of Los Angeles, California, during summer 1986. The V/Ni ratio, 1.7 ± 0.4, was very similar to the ratios measured in fine particles from combusted Kuwaiti oil, 1.4 ± 0.9. Bromine, copper, zinc, and arsenic/lead were also observed at levels between 2 and 190 ng/m3. The presence of massive amounts of fine, typically alkaline soils in the Kuwaiti smoke plumes significantly modified their behavior and probably mitigated their impacts, locally and globally.

Individual aerosol particles in ambient and updraft conditions below convective cloud bases in the Oman mountain region

“…The sources of NaCl in the atmosphere are twofold in the UAE: industrial and local sea salt. NaCl is a major component in smoke from petroleum processing plants due to the evaporation of brines in the combustion process [ Cahill and Wilkinson , ; Ferek et al ., ]. Sea salt is typically identified from ionic ratios between Mg, Na, K, and Ca close to seawater composition [ Pósfai et al ., ].…”

Summertime aerosol chemical components in the marine boundary layer of the Arctic Ocean

“…A 2048 multichannel analyzer (MCA) was used to record and analyze the XRF spectra. The continuous X‐ray spectrum was used for rapid multielement detection and was favorable for qualitative analysis as described in detail in previous references [ Cahill et al , 1992; Reid et al , 1994; Khodzher et al , 2000; Bench et al , 2002; Cahill , 2003; Yue et al , 2004].…”

“…Because of the complex nature of the aerosol samples and the low concentrations involved, synchrotron radiation X‐ray fluorescence (SR‐XRF) analysis was utilized for this study because it satisfies the requirements of being sensitive, element‐specific, and accurate. SR‐XRF is applicable to major, minor and trace constituents of atmospheric aerosols and is becoming an important tool in atmospheric chemistry [ Cahill et al , 1992; Reid et al , 1994; Khodzher et al , 2000; Bench et al , 2002; Cahill , 2003; Yue et al , 2004].…”

Rate constants for the reactions of chlorine atoms with a series of unsaturated aldehydes and ketones at 298 K: structure and reactivity

“…[1][2][3][4][5][6] In addition, chlorine atom chemistry has been observed in the Arctic at polar sunrise [7][8][9][10][11][12][13] and may have occurred in the plumes from the burning of oil wells in Kuwait due to the presence of brine. [14][15][16][17][18][19][20][21] Molecular chlorine, Cl 2 , a precursor to atomic chlorine has been measured in marine air masses at concentrations up to $150 ppt (parts per trillion). 22 Non-HCl inorganic gaseous chlorine compounds, hypothesized to be mainly Cl 2 ranging from 13 to 127 ppt were measured indirectly using mist chambers at coastal sites.…”