Black carbon and other species at a high-elevation European site (Mount Sonnblick, 3106 m, Austria): Concentrations and scavenging efficiencies

Autor: W. Tscherwenka, H. Puxbaum, A. Kasper-Giebl, Regina Hitzenberger, Axel Berner, R. Kromp, Andreas Limbeck
Rok vydání: 2000
Předmět:
Zdroj: Scopus-Elsevier
ISSN: 0148-0227
DOI: 10.1029/2000jd900349
Popis: During a recent measurement project, several intensive campaigns were performed on Mount Sonnblick (3106 m above sea level) in the Austrian central range of the Alps. Cloud water and interstitial aerosol samples were obtained from supercooled clouds by using a specially designed cloud water sampler [Kruisz et al., 1993]. The samples were analyzed for black carbon (BC) by an optical technique (integrating sphere [Hitzenberger et al. 1996]) using liquid samples, for major inorganic ions by ion chromatography and for total carbon (TC) by a combusion method. During the fall campaign of 1996, cloud water BC concentrations ranged from 0.45 to 3.64 μg/mL (average concentration 0.85 μg/mL). During the spring 1997 campaign, cloud water BC concentrations ranged from 0.55 to 2.95 μg/mL (average concentration 1.07 μg/mL). The dominant ion in cloud water was SO42− with concentrations from 0.36 to 86.5 μg/mL (average 6.83 μg/mL) in fall 1996 and 0.31–15.4 μg/mL (average 3.06 μg/mL) in spring 1997. In the individual samples, the BC/SO42− ratio ranged from 0.036 to 1.2 (average 0.316) in fall 1996 and 0.036 to 2.04 (average 0.79) in spring 1997. The extreme values were usually confined to short periods within one cloud event. Scavenging efficiencies e were calculated by using cloud water and interstitial aerosol concentrations from samples obtained simultaneously with the cloud water sampler for the 1997 campaign. For BC, eBC = 0.74 (±0.19) was found, while the values for SO42− and TC were eSO4 = 0.91 (±0.08) and eTC = 0.57 (±0.21), respectively. The findings of an earlier study [Kasper-Giebl et al., 2000], where eSO4 depended on the liquid water content, were confirmed here for all the three substances.
Databáze: OpenAIRE