Atmospheric measurements of gas-phase HNO<sub>3</sub> and SO<sub>2</sub> using chemical ionization mass spectrometry during the MINATROC field campaign 2000 on Monte Cimone

Abstract

Abstract. The EU-project MINATROC (MINeral dust And TROpospheric Chemistry) aims at enabling an estimation of the influence of mineral dust, a major, but to date largely ignored component of tropospheric aerosol, on tropospheric oxidant cycles. Within the scope of this project continuous atmospheric measurements of gas-phase HNO 3 and SO 2 were conducted in June and July 2000 at the CNR WMO station, situated on Monte Cimone (MTC) (44 • 11 N -10 • 42 E, 2165 m asl), Italy. African air transporting dust is occasionally advected over the Mediterranean Sea to the site, thus mineral aerosol emitted from Africa will encounter polluted air masses and provide ideal conditions to study their interactions. HNO 3 and SO 2 were measured with an improved CIMS (chemical ionization mass spectrometry) system for ground-based measurements that was developed and built at MPI-K Heidelberg. Since HNO 3 is a very sticky compound special care was paid for the air-sampling and backgroundmeasurement system. Complete data sets could be obtained before, during and after major dust intrusions. For the first time these measurements might provide a strong observational indication of efficient uptake of gas-phase HNO 3 by atmospheric mineral-dust aerosol particles.

Seasonal variation of water-soluble inorganic components in aerosol size-segregated at the puy de Dôme station (1,465 m a.s.l.), France

“…The autumn maximum could be attributed to the high number of samples originating from Mediterranean region (see later, section III.5.1). In the PM 10-1 , it is bound with alkaline sea salt and/or mineral dust particles (Harrison and Kitto 1990;Pakkanen et al 1996;Hanke et al 2003;Krueger et al 2004;Sullivan et al 2007). The reaction of HNO 3 to sea salt has been pointed out in several publications (Robbins et al 1959;Martens et al 1973;Harrison and Pio 1983;Pakkanen et al 1996;Plate and Schulz 1997;Vignati et al 2001;Sørensen et al 2005), resulting in a loss of Cl -relative to the Cl -/Na + ratio in the sea composition.…”

A review of atmospheric chemistry observations at mountain sites

“…The phenomena of low O 3 and high dust concentrations have been observed in the field (e.g., Bonasoni et al 1997;Prospero et al 1995). As part of the Mineral Dust and Tropospheric Chemistry (MINATROC) project, which was an intensive field measurement campaign conducted at CMN from June 1 to July 5, 2000 (Balkanski et al 2003;Bauer et al 2004;Bonasoni et al 2004;de Reus et al 2005;Fischer et al 2003;Gobbi et al 2003;Hanke et al 2003;Putaud et al 2004;Van Dingenen et al 2005) and at IZO from July 15 to August 15, 2002(de Reus et al 2005Salisbury et al 2006;Umann et al 2005). Their aim was to fully characterize gas and aerosol species with a complete set of measurements in order to identify the heterogeneous reactions of dust.…”

“…Putaud et al (2004) suggested that NO 3 − was shifted toward the aerosol super-μm fraction in the presence of dust. Hanke et al (2003) and Umann et al (2005) observed an efficient uptake of gaseous HNO 3 by mineral dust aerosol particles, thereby suggesting that mineral dust might be a significant sink for HNO 3 in the troposphere. Hence, it could affect the photochemical cycles and O 3 production.…”

An aircraft-borne chemical ionization – ion trap mass spectrometer (CI-ITMS) for fast PAN and PPN measurements

“…CIMS techniques provide generally a high time resolution (∼1 s) in combination with low detection limits in the range of a few pmol mol −1 . CIMS was originally introduced in atmospheric research by Arnold et al (1978) and now is established as a powerful method for the measurement of a series of trace gases (Kiendler et al, 2000;Neuman et al, 2000;Nowak et al, 2002;Thornton et al, 2002;Hanke et al, 2003;Slusher et al, 2004;Speidel et al, 2007;Kercher et al, 2009), for a recent review see for example Huey (2007).…”