Open AccessInteraction of mineral dust with gas phase nitric acid and sulfur dioxide during the MINATROC II field campaign: First estimate of the uptake coefficient from atmospheric data
Author(s) -
Umann B.,
Arnold F.,
Schaal C.,
Hanke M.,
Uecker J.,
Aufmhoff H.,
Balkanski Y.,
Van Dingenen R.
Publication year - 2005
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2005jd005906
Subject(s) - mineral dust , ozone , chemistry , nitric acid , environmental chemistry , nitrogen dioxide , sulfur dioxide , troposphere , aerosol , atmosphere (unit) , mineral , trace gas , atmospheric chemistry , analytical chemistry (journal) , mineralogy , atmospheric sciences , inorganic chemistry , meteorology , geology , physics , organic chemistry
Mineral dust, one of the most abundant aerosols by mass in the atmosphere, may have a lasting but to date almost unexplored effect on the trace gases nitric acid (HNO 3 ) and sulfur dioxide (SO 2 ). These gases have an important influence on, for example, the tropospheric ozone cycle, aerosol formation or acid rain. Within the second part of the MINATROC project (Mineral Dust and Tropospheric Chemistry) we investigated the interaction of mineral dust with gaseous HNO 3 and SO 2 . The measurements were performed on a high mountain plateau (Izaña, Tenerife, 2367 m asl) using the highly sensitive CIMS (Chemical Ionization Mass Spectrometry) technique. During five periods of medium and one period of high atmospheric dust load, the HNO 3 concentration decreased with increasing dust concentrations, and in all cases the HNO 3 detection limit was reached. From the HNO 3 decrease the uptake coefficient was calculated for the first time on the basis of in situ measurements. For the observed events, varied between 0.017 and 0.054. Moreover, during the dust events a significant decrease of ozone (O 3 ) of the order of 30% was detected. The measurements and the analyses made in this paper show that the direct uptake of O 3 on dust is a minor pathway for O 3 depletion compared to the indirect effect, i.e., HNO 3 depletion on dust which takes away a source of the O 3 precursors nitrogen oxides. In contrast, a general interaction between SO 2 and mineral dust was not observed. Positive as well as negative and no correlations between SO 2 and mineral dust were detected.